KR20050015309A - Apparatus and method for assigning connection identifier in broadband wireless access communication system - Google Patents

Abstract

PURPOSE: A CID(Connection Identifier) assignment system and method is provided to eliminate a signaling overhead and a redundancy, caused by a transmission or receiving of a CID, by making an SS(Subscriber Station) and a BS(Base Station) recognize each other though CIDs are not transmitted or received specially, and to minimize a BS access delay because the BS performs an initial ranging corresponding to a state of the SS. CONSTITUTION: The system comprises a controller(1411), a CID generator(1413), a basic CID assignment management table(1415), and transport CID assignment management tables(1419-1,N). The controller(1411) transmits a value, separating a CID into a determination part and a basis part, and purposes to the CID generator(1413). The CID generator(1413) receives the data from the controller(1411) and generates a CID based on the received data. In a case that the received data is a basic CID, the CID generator(1413) generates a basic CID according to a basic CID assignment sequence stored at the basic CID assignment management table(1415), and updates the basic CID assignment management table(1415). In a case that the received data is a transport CID, the CID generator(1413) generates a transport CID according to a transport CID assignment sequence stored at the transport CID assignment management tables(1419-1,N), and updates the transport CID assignment management tables(1419-1,N).

Description

Apparatus and method for allocating a connection identifier in a broadband wireless access communication system {APPARATUS AND METHOD FOR ASSIGNING CONNECTION IDENTIFIER IN BROADBAND WIRELESS ACCESS COMMUNICATION SYSTEM}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a broadband wireless access (BWA) communication system, and more particularly for a wireless link between a subscriber station (SS) and a base station (BS). An apparatus and method for allocating a connection identifier are provided.

In the next generation communication system, the 4th generation (4G: 4G) communication system, various quality of service having a transmission rate of about 100 Mbps (QoS: Quality of Service, hereinafter referred to as "QoS") Active research for providing users with services has been conducted. Currently, third generation (3G) communication systems generally support a transmission rate of about 384kbps in an outdoor channel environment having a relatively poor channel environment, and an indoor channel having a relatively good channel environment. It supports up to 2Mbps transmission speed even in the environment. On the other hand, a wireless local area network (LAN) system and a wireless metropolitan area network (MAN) system are generally 20 Mbps to It supports a transfer rate of 50Mbps. Therefore, 4G communication system currently supports a high-speed service to be provided in the 4G communication system by developing a new communication system in the form of guaranteeing mobility and QoS in a wireless LAN system and a wireless MAN system that guarantee a relatively high transmission speed. There is a lot of research going on.

However, the wireless MAN system is suitable for high-speed communication service support because of its wide coverage and high transmission speed, but it does not consider the mobility of the user, that is, the subscriber station. Handoff due to high speed movement is also not considered at all. Next, the structure of the wireless MAN system will be described with reference to FIG. 1.

FIG. 1 is a diagram schematically illustrating a general Institute of Electrical and Electronics Engineers (IEEE) 802.16a communication system.

Before describing FIG. 1, the IEEE 802.16a communication system includes orthogonal frequency division multiplexing (OFDM) / orthogonal frequency division multiplexing (OFDMA). Wireless MAN communication system using an Access (hereinafter, referred to as "OFDMA") method. Of course, although there exist other systems besides the IEEE 802.16a communication system in the wireless MAN system, the IEEE 802.16a communication system will be described with reference to FIG.

Before explaining FIG. 1, the wireless MAN system is a BWA communication system, and its service area is wider than that of the wireless LAN system and supports a high transmission speed. The IEEE 802.16a communication system is a system in which the OFDM scheme and the OFDMA scheme are applied to support a broadband transmission network in a physical channel of the wireless MAN system. Since the IEEE 802.16a communication system applies the OFDM / OFDMA scheme to the wireless MAN system, high-speed data transmission is possible by transmitting a physical channel signal using a plurality of sub-carriers. Of course, the IEEE 802.16a communication system may use a single carrier method instead of the OFDM / OFDMA method. Here, only the OFDM / OFDMA method will be described.

Referring to FIG. 1, the IEEE 802.16a communication system has a single cell structure, and a plurality of subscriber stations 110, 120 managed by the base station 100 and the base station 100, It consists of 130. Signal transmission and reception between the base station 100 and the subscriber stations (110, 120, 130) is performed using the OFDM / OFDMA method.

As described above, the IEEE 802.16a communication system currently considers only a fixed state of a subscriber station, that is, a state in which the mobility of the subscriber station is not considered at all and a single cell structure. Meanwhile, the IEEE 802.16e communication system is a system that considers the mobility of a subscriber station in the IEEE 802.16a communication system. The IEEE 802.16e communication system will be described with reference to FIG.

2 is a diagram schematically illustrating a general IEEE 802.16e communication system.

Before describing FIG. 2, as described above, the IEEE 802.16e communication system is a communication system considering the mobility of a subscriber station in the IEEE 802.16a communication system. Considering the mobility of a subscriber station in the IEEE 802.16a communication system, a multi-cell structure and a handoff of the subscriber station between the multi-cells can be considered. Therefore, the IEEE 802.16e communication system structure is a multi-cell. Architecture and a communication system considering the multi-cell handoff. The IEEE 802.16e communication system is also a wireless MAN system using the OFDM / OFDMA scheme. Like the IEEE 802.16a communication system, a single carrier scheme may be used instead of the OFDM / OFDMA scheme. Here, only the OFDM / OFDMA scheme is used. This will be described in consideration.

Referring to FIG. 2, the IEEE 802.16e communication system has a multi-cell structure, that is, a cell 200 and a cell 250, and the base station 210 managing the cell 200 and the cell ( Base station 240 that manages 250 and a plurality of subscriber stations (211), 213, 230, 251, 253. In addition, signal transmission and reception between the base stations 210 and 240 and the subscriber stations 211, 213, 230, 251, and 253 are performed using the OFDM / OFDMA scheme. However, among the subscriber stations 211, 213, 230, 251, and 253, the subscriber station 230 is a border area, that is, handoff, between the cell 200 and the cell 250. It exists in the area, and thus supports handoff for the subscriber station 230 to support mobility for the subscriber station 230.

In a wireless communication system such as the IEEE 802.16a communication system and the IEEE 802.16e communication system, a connection between the subscriber station and the base station (hereinafter referred to as a "connection") is required for the subscriber station to receive a service from the base station. Must be set. Here, the connection is referred to as a Media Access Control (MAC) set up to transmit and receive information, that is, control data and user data between the subscriber station and the base station. It means the connection between peers. The number and types of connections established between the subscriber station and the base station are plural. Therefore, a connection identifier (CID) is used to distinguish the connection established between the subscriber station and the base station. Is assigned. Here, the CID is allocated by the base station.

In the IEEE 802.16a communication system and the IEEE 802.16e communication system, the CID is transmitted through a header area of a MAC-protocol data unit (hereinafter referred to as a "PDU"). The IEEE 802.16a communication system and the IEEE 802.16e communication system differ only in whether they support mobility of a subscriber station. For convenience of explanation, the IEEE 802.16e communication system will be described as an example. Next, the MAC-PDU structure will be described with reference to FIG. 3.

3 is a diagram schematically illustrating a MAC-PDU structure of a general IEEE 802.16e communication system.

Referring to FIG. 3, the MAC-PDU includes a MAC header area 311 and a MAC payload area 313. The MAC header area 311 is an area including a header of the MAC-PDU, and the CID is included in the MAC header area 311. A MAC message or a MAC Service Data Unit (SDU) is transmitted through the MAC payload region 313. Here, the MAC-SDU represents actual user data.

The CIDs currently used in the IEEE 802.16e communication system are shown in Table 1 below.

The CIDs shown in Table 1 will be described.

(1) Initial Ranging CID

The initial ranging CID indicates a CID used when performing initial ranging, and the initial ranging CID value is "0x0000". In this case, the initial ranging is a ranging performed by a base station to acquire synchronization with a subscriber station, and the initial ranging matches a correct time and frequency offset between the subscriber station and the base station and transmit power. Range is performed to adjust).

(2) basic CID

The basic CID represents a CID used when transmitting a message having a relatively short length and urgently transmitted, and the basic CID value is "0x0001 to m". Here, m is a parameter that can be variably selected according to the system situation. For example, as described above, the initial ranging is a ranging performed by the base station to obtain synchronization with the subscriber station, and the base station performs the MAC address of the subscriber station from the subscriber station through the initial ranging procedure. address). The base station generates the basic CID by mapping with the received MAC address of the subscriber station.

(3) primary management CID

The first management CID indicates a CID used when transmitting a message having a relatively long length and a relatively low urgency, and the first management CID value is “m + 1 to 2m”. For example, the base station receives the MAC address of the subscriber station from the subscriber station through the initial ranging procedure, and generates the first management CID together with the basic CID by mapping with the received MAC address of the subscriber station. do.

(4) secondary management CID (secondary management CID)

The second management CID has a relatively low urgency and indicates a CID used when transmitting a message related to a standard protocol, and the second management CID value is "2m + 1 to 0xFEFF".

(5) transport CID

The transport CID represents a CID used when transmitting data, and the transport CID value is "2m + 1-0xFEFF". The transport CID is allocated one by one whenever a subscriber station establishes a connection to receive traffic from a base station. Here, the transport CIDs are allocated one by one according to the type of the traffic, and a plurality of transport CIDs are not allocated to the same traffic type.

(6) multicast polling CID

The multicast polling CID represents a CID used to distinguish a group for a bandwidth request, and the multicast polling CID value is “0xFF00 to 0xFFFD”. The multicast polling CID is a CID commonly used by all subscriber stations belonging to the base station.

(7) padding CID

The padding CID represents a CID used to indicate padding, and the padding CID value is "0xFFFE". The padding CID is a CID commonly used between the base station and subscriber stations.

(8) broadcast CID

The broadcast CID indicates a CID used to transmit a broadcast message, and the broadcast CID value is "0xFFFF".

Among the CIDs of Table 1, the basic CID, the first management CID, and the second management CID are CIDs used to transmit control data. Among the CIDs of Table 1, the basic CID, the first management CID, the second management CID, and the transport CID are CIDs assigned to each of the subscriber stations, and the transport CID is associated with the subscriber station. Since each time the traffic connection is established between the base stations can be assigned a plurality.

In Table 1, the CIDs currently used in the IEEE 802.16e communication system have been described. Next, operations that actually use the CIDs described in Table 1 will be described.

First, a process of accessing a base station when a subscriber station is powered on and reconnected after initial access will be described with reference to FIG. 4.

4 is a signal flow diagram schematically illustrating a process of accessing a base station when a subscriber station is powered on and reconnected after initial access in a general IEEE 802.16e communication system.

In FIG. 4, an initial base station access procedure will be described based on a code division multiple access (CDMA) scheme. Referring to FIG. 4, first, the subscriber station 400 monitors all frequency bands preset in the subscriber station 400 as it is powered on. ) Detects a pilot channel signal having a Carrier to Interference and Noise Ratio (CINR) (hereinafter referred to as "CINR"). In addition, the subscriber station 400 determines that the base station 450 having transmitted the pilot channel signal having the strongest pilot CINR is the base station 450 to which the subscriber station 400 itself belongs, and the base station 450 In step 411, the system receives a preamble of a downlink frame transmitted by the MS, and acquires a system synchronization with the base station 450 (step 411).

As described above, when system synchronization is acquired between the subscriber station 400 and the base station 450, the base station 450 broadcasts base station information related to the base station 450 to the subscriber station 400 (413). step). The base station information includes a Downlink Channel Descriptor (DCD) message, an Uplink Channel Descriptor (UCD) message, and It is broadcast through a DL-MAP message, a UL-MAP message, a neighbor base station advertisement (NBR_ADV: NBR_ADV) message, and the like.

The DCD message is a MAC message for broadcasting a downlink burst profile, that is, downlink physical channel information, and the UCD message is a MAC message for broadcasting an uplink burst profile, that is, uplink physical channel information. The DL-MAP message is a MAC message for broadcasting the MAP of the downlink frame, and indicates a location of the downlink frame at which data of the subscriber station exists. In addition, the DL-MAP message includes a PHY (PHYsical) Synchronization set corresponding to a modulation scheme and a demodulation scheme applied to a physical channel to obtain synchronization, and a count corresponding to a configuration change of the DCD message. Is assigned to each of the rangings, a DCD count indicating a base station ID, a base station ID indicating a base station IDentifier, a number of DL-MAP elements n indicating a number of elements existing after the base station ID, Contains information about ranging codes.

The UL-MAP message is a MAC message for broadcasting the MAP of the uplink frame, and indicates a position of the uplink frame at which the data of the subscriber station should be present. In addition, the UL-MAP message may include an Uplink Channel ID indicating an uplink channel ID used, a UCD count indicating a count corresponding to a configuration change of a UCD message, and elements that exist after the UCD count. Number of UL_MAP Elements n indicating the number is included. The NBR_ADV message is a message broadcasted when a subscriber station is handed off and is a broadcast message indicating physical information about neighbor base stations of a base station currently providing a service to the subscriber station. The NBR_ADV message may include N_NEIGHBORS indicating the number of neighbor base stations, a neighbor BS-ID indicating an identifier (ID) of the neighbor base stations, a Configuration Change Count indicating a number of configuration changes, and the neighbor It includes a physical frequency indicating the physical channel frequency of the base station, and other neighbor information (TLV Encoded Neighbor Information) indicating other information related to the neighbor base station in addition to the information.

As such, when the base station 450 broadcasts base station information on the base station 450 itself, the subscriber station 400 receives the broadcast base station information to obtain downlink synchronization with the base station 450 ( Step 415). Thus, the subscriber station 400 having downlink synchronization with the base station 450 sends a ranging request (RNG-REQ: Ranging-Request, hereinafter, " RNG-REQ ") message to the base station 450. (Step 417). Here, the RNG-REQ message is a message for requesting the initial ranging, and includes an initial ranging CID and a MAC address of the subscriber station 400.

The base station 450 receives the RNG-REQ message from the subscriber station 400, maps the MAC address included in the received RNG-REQ message to the base station CID for the subscriber station 400, The first management CID is allocated (step 419). Here, the base station 450 checks whether the MAC address of the subscriber station 400 is registered in the MAC address list of subscriber stations currently registered in the base station 450. If the MAC address of the subscriber station 400 is registered in the MAC address list, the base station 450 determines that the subscriber station 400 regains synchronization after losing the synchronization once. In accordance with the reconnection, the base station reassigns the default CID assigned to the subscriber station 400 and the first management CID. If the MAC address of the subscriber station 400 is not registered in the MAC address list, the base station 450 determines that the subscriber station 400 is initially connected, and the subscriber station ( The MAC address of 400 is registered in the MAC address list, and the basic CID and the first management CID are allocated by mapping the MAC address with the MAC address of the subscriber station 400. As such, whenever the base station 450 receives the RNG-REQ message, the base station 450 needs to perform a MAC address list search managed by the base station 450 itself. Therefore, an access delay may occur due to the MAC address list search.

Meanwhile, the base station 450 allocates a basic CID and a first management CID to the subscriber station 400, and then responds to the RNG-REQ message by the subscriber station 400 with a ranging response (RNG). -RSP: A Ranging-Response (hereinafter, referred to as "RNG-RSP") message is transmitted (step 421). Here, the RNG-RSP message includes the allocated basic CID, the first management CID, and uplink synchronization information. Upon receiving the RNG-RSP message, the subscriber station 400 acquires base station uplink synchronization, and completes initial ranging by adjusting frequency and power (step 423).

In this way, after completing the initial ranging, the subscriber station 400 will call the subscriber station basic capacity negotiation request (SBC-REQ) to the base station 450 (hereinafter referred to as "SBC-REQ"). In step 425, the message is transmitted. Here, the SBC-REQ message is a MAC message transmitted by the subscriber station 400 to negotiate a basic capacity with the base station 450. The SBC-REQ message can be supported by the subscriber station 400 in modulation. information on a modulation and coding scheme is included. The base station 450 receives the SBC-REQ message from the subscriber station 400, checks the modulation and coding scheme supported by the subscriber station 400 included in the received SBC-REQ message, and then the As a response message to the SBC-REQ message, a basic capacity negotiation response (SBC-RES: Subscriber Station's Basic Capability Negotiation Response, hereinafter referred to as "SBC-RES") message is transmitted (step 427).

By receiving the SBC-RES message, the subscriber station 400 completes the basic capacity negotiation of the subscriber station 400 (step 429), and requests an encryption key management request to the base station 450 (PKM-REQ: Privacy). Key Management Request, hereinafter referred to as "PKM-REQ" message (step 431). Here, the PKM-REQ message is a MAC message for subscriber station authentication and includes unique information of the subscriber station 400. The base station 450 receiving the PKM-REQ message performs authentication with an authentication server (AS) with the unique information of the subscriber station 400 included in the PKM-REQ. When the subscriber station 400 is an authenticated subscriber station as a result of the authentication, the base station 450 responds to the subscriber station 400 as a response message to the PKM-REQ message (PKM-RES: Privacy Key). Management Respone, hereinafter referred to as " PKM-RES ") message (step 433). Here, the PKM-RES message includes an authentication key (AK) assigned to the subscriber station 400 and a traffic encryption key (TEK).

By receiving the PKM-RES message, the subscriber station 400 acquires an encryption key at the same time as completing the authentication of the subscriber station 400 itself (step 435) and requests registration with the base station 450 (REG- REQ: Registration Request, hereinafter referred to as "REG-REQ") (step 437). Here, the REG-REQ message includes subscriber station registration information of the subscriber station 400. The base station 450 receiving the REG-REQ message detects subscriber station registration information included in the REG-REQ message, registers the subscriber station 400 with the base station 450, Allocate a second management CID for 400). The base station 450 that has allocated the second management CID is called a registration response (REG-RES), which is a response message to the REG-REQ message, to the subscriber station 400. Message) (step 439). Here, the REG-RES message includes the allocated second management CID and the registered subscriber station registration information.

By receiving the REG-RES message, the subscriber station 400 completes registration of the subscriber station 400 itself and at the same time acquires a second management CID (step 441). As such, when the subscriber station registration is completed, the subscriber station 400 is assigned three CIDs, namely, three CIDs of an initial basic CID, a first management CID, and a second management CID. After the subscriber station 400 completes registration of the subscriber station with the base station 450, an internet protocol (IP) connection is established between the subscriber station 400 and the base station 450, and the connected internet protocol is established. Operational information is downloaded (step 443). Thereafter, a service flow is connected between the subscriber station 400 and the base station 450 (step 445). Here, the service flow refers to a flow in which the MAC-SDU is transmitted and received through a connection having an arbitrary Quality of Service (QoS). As described above, since the transport CID must be allocated in transmitting and receiving the MAC-SDU, that is, the traffic, the subscriber station 400 is assigned a transport CID when the service flow is connected. As such, when the service flow is connected, the service is actually performed between the subscriber station 400 and the base station 450 (step 447).

In FIG. 4, a process of accessing a base station during initial access or reconnection after initial access according to power-on of a subscriber station has been described. Next, a process of accessing a base station during handoff of a subscriber station will be described with reference to FIG.

FIG. 5 is a signal flowchart schematically illustrating a process of accessing a base station during handoff of a subscriber station in a general IEEE 802.16e communication system.

Referring to FIG. 5, as described above with reference to FIG. 4, even when a service is performed between the subscriber station 400 and the base station 450 (step 511), the base station 450 periodically broadcasts base station information (513). step). When the subscriber station 400 that receives the base station information broadcast by the base station 450 detects that the handset needs to be handed off, the subscriber station 400 performs handoff among neighboring base stations included in the NBR_ADV message of the base station information. The base station to determine to determine (step 515). After determining the base station to be handed off, the subscriber station 400 notifies that the base station 450 is to be handed off, i.e., the existing base station (step 517).

Thereafter, the subscriber station 400 performs a series of processes for continuously performing the service with the base station, that is, the base station 500 determined to handoff. A series of processes performed by the subscriber station 400 to perform a service performed by the base station 450, which is an existing base station, by the base station 500, which is the base station to be handed off, is initially connected and reconnected. It is almost similar to the process. That is, since operations of steps 519 to 543 of FIG. 5 are the same as those of steps 413 to 437 described with reference to FIG. 4, detailed descriptions thereof will be omitted.

When the base station 500 receives the REG-REQ message from the subscriber station 400, the base station 500 detects the subscriber station registration information included in the REG-REQ message and sends the subscriber station 400 to the base station 500. It registers and allocates a second management CID and a transport CID for the subscriber station 400. The base station 500 having allocated the second management CID and the transport CID transmits a REG-RES message to the subscriber station 400 (step 545). Here, the REG-RES message includes the allocated second management CID, transport CID, mapping table, and the registered subscriber station registration information. The mapping table is a table showing a mapping relationship between transport CIDs allocated by the subscriber station 400 to the base station 450 which is an existing base station and transport CIDs assigned by the base station 500 which is the base station to be handed off. , It is shown in Table 2 below.

As shown in Table 2, the mapping table indicates to which transport CIDs the transport CIDs allocated by the existing base station are mapped to the base station to be handed off. However, when the subscriber station 400 has a large number of traffic serving the base station 450, the time required for transmitting the REG-RSP message because the number of transport CIDs stored in the mapping table is large. This increases, resulting in a delay in base station access time during handoff.

Next, the CID classification process according to the parameter for determining the CID value in the IEEE 802.16e communication system will be described with reference to FIG. 6.

6 is a diagram schematically illustrating a CID classification process according to a CID value determination parameter in a general IEEE 802.16e communication system.

FIG. 6 illustrates a CID usage classification process, that is, a CID type classification process, when the CID value determination parameter m is 1023 (m = 1023). Referring to FIG. 6, when the CID values 0 (600) correspond to initial ranging CIDs, CID values 1 to 1023 (601) indicate basic CIDs, and CID values 1024 when corresponding to the CID values described in Table 1 above. 2046 are the first management CIDs, CID values 2047 to 3069 (603) are the second management CIDs, CID values 3070 to 65279 (604) are the transport CIDs, and CID values 65280 to 65533 (605) are: CID value 65534 (606) represents a padding CID, and CID value 65535 (607) represents a broadcast CID.

As described above, the CIDs currently used in the IEEE 802.16a communication system and the IEEE 802.16e communication system are in a state in which only a range of their values is determined for each CID type, and no connection relationship between CIDs is defined. Not. Therefore, in order to perform a service between the subscriber station and the base station, the subscriber station must be allocated CIDs necessary for accessing the base station. As such, since a subscriber station must be allocated CIDs from the base station, signaling overhead is generated by allocating the CIDs. In addition, there is a problem that excessive redundancy due to the CID allocation is generated by transmitting the CIDs through separate signalings. In addition, since the subscriber station attempts to access the base station by using the initial ranging CID during initial access, reconnection, and handoff, the base station manages the current base station each time during the initial access, reconnection, and handoff. Since the MAC address list of the subscriber station is to be searched, a base station access delay occurs according to the MAC address list search. In addition, as described above, the subscriber station receives a mapping table indicating how transport CIDs allocated from the existing base station are mapped at the base station to be handed off when the subscriber station is handed off. There is a problem that a connection delay occurs.

Accordingly, an object of the present invention is to provide an apparatus and method for allocating a connection identifier in a broadband wireless access communication system.

Another object of the present invention is to provide an apparatus and method for allocating a connection identifier for minimizing signaling load and redundancy in a broadband wireless access communication system.

Another object of the present invention is to provide an apparatus and method for allocating a connection identifier for minimizing a base station access delay time in a broadband wireless access communication system.

It is still another object of the present invention to provide an apparatus and method for allocating connection identifiers so as to have correlations between connection identifiers allocated to subscriber stations in a broadband wireless access communication system.

A first apparatus of the present invention for achieving the above objects; In the apparatus for allocating a connection identifier in a broadband wireless access communication system, if it is detected that a connection identifier should be allocated, a controller for detecting a type of the connection identifier to be allocated and controlling to generate the connection identifier according to the detected type; And a connection identifier generated such that the connection identifier has a first part and a second part and has information indicating the type according to a combination of information included in the first part and the second part under the control of the controller. And a generator.

A second device of the present invention for achieving the above objects; An apparatus for allocating a connection identifier in a broadband wireless access communication system, the apparatus comprising: a controller configured to detect all types that the connection identifier may have, and generate connection identifiers corresponding to each of the detected types; A connection identifier generator for generating the connection identifiers such that the connection identifier has a first part and a second part, and has information indicating the type according to a combination of information included in the first part and the second part. Characterized by including.

A third apparatus of the present invention for achieving the above objects; An apparatus for allocating a connection identifier in a broadband wireless access communication system, comprising: a subscriber station requesting ranging to an base station including an initial ranging connection identifier, a medium access control address, and a medium access control address according to the ranging request; And the base station assigning a corresponding basic connection identifier and responding to the ranging request to the subscriber station, including the basic connection identifier and uplink synchronization information.

A fourth device of the present invention for achieving the above objects; An apparatus for allocating a connection identifier in a broadband wireless access communication system, comprising: a subscriber station requesting ranging to a base station including a reconnection ranging connection identifier and a medium access control address; and managed by the base station according to the ranging request. Search for a medium access control address list, reassign a basic connection identifier that is already assigned to the ranging requesting terminal to the basic connection identifier of the subscriber station, and assign the reassigned basic connection identifier and uplink synchronization information. And the base station responding to the ranging request to the subscriber station.

A fifth apparatus of the present invention for achieving the above objects; In the apparatus for allocating a connection identifier in a broadband wireless access communication system, if it is determined that handoff should be performed to a second base station different from the first base station while receiving a service from the first base station, a handoff ranging connection identifier is transmitted to the second base station. And a subscriber station requesting ranging including a medium access control address, a basic connection identifier corresponding to the medium access control address according to the ranging request, and the basic connection identifier and uplink synchronization information. And a second base station responding to the ranging request to a subscriber station.

The first method of the present invention for achieving the above objects; In the method of allocating a connection identifier in a broadband wireless access communication system, if it is detected that a connection identifier should be allocated, detecting the type of the connection identifier to be allocated, detecting the type of the connection identifier, and then detecting the first part and the first part. And having the two parts and assigning the connection identifier to have the information indicating the type according to the combination of the information included in the first part and the second part.

A second method of the present invention for achieving the above objects; A method of allocating a connection identifier in a broadband wireless access communication system, the method comprising: detecting all kinds of connection identifiers, detecting all kinds of connection identifiers, and then detecting a first part for each of the kinds. And having a second part, allocating the connection identifier to have the information indicating the type according to a combination of the information included in the first part and the second part.

The third method of the present invention for achieving the above objects; In the method of allocating a connection identifier in a broadband wireless access communication system, the subscriber station requests ranging to the base station including an initial ranging connection identifier and a medium access control address, and the base station that detects the ranging request includes: And allocating a basic connection identifier corresponding to the medium access control address and responding to the ranging request to the subscriber station including the basic connection identifier and uplink synchronization information.

A fourth method of the present invention for achieving the above objects; A method of allocating a connection identifier in a broadband wireless access communication system, the subscriber station requesting ranging to a base station including a reconnection ranging connection identifier and a medium access control address, and the base station that detects the ranging request includes: Retrieving a list of media access control addresses managed by a base station to detect a basic connection identifier already assigned to the ranging requesting subscriber station, and the base station converts the detected basic connection identifier to a base station of the subscriber station. And reassigning a connection identifier, and responding to the ranging request to the subscriber station, including the reassigned basic connection identifier and uplink synchronization information.

The fifth method of the present invention for achieving the above objects; In the method of allocating a connection identifier in a broadband wireless access communication system, when the subscriber station receiving the service from the first base station determines that the terminal should be handed off to a second base station different from the first base station, handoff ranging to the second base station Requesting ranging, including a connection identifier and a medium access control address, and the second base station that detects the ranging request allocates a default connection identifier corresponding to the medium access control address, And responding to the ranging request to the subscriber station by including uplink synchronization information.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that in the following description, only parts necessary for understanding the operation according to the present invention will be described, and descriptions of other parts will be omitted so as not to distract from the gist of the present invention.

The present invention relates to a connection identifier (CID) assigned to a subscriber station (SS) in a broadband wireless access (BWA) communication system. A CID allocation scheme for minimizing signaling load and redundancy according to the CID allocation when a base station is connected to each other has a correlation with each other. In addition, in the present invention, as the BWA communication system, the Institute of Electrical and Electronics Engineers (IEEE) 802.16a communication system and the IEEE 802.16e communication system, that is, orthogonal frequency division multiplexing (OFDM) as described in the prior art section. In the following description, a communication system employing an Orthogonal Frequency Division Multiplexing Access (OFDMA) scheme and an Orthogonal Frequency Division Multiplexing Access (OFDMA) scheme will be considered. The IEEE 802.16a communication system and the IEEE 802.16e communication system differ only in whether they support mobility of a subscriber station (SS). For convenience of description, the IEEE 802.16e communication system will be described as an example. do.

The CIDs proposed in the present invention are shown in Table 3 below.

The CIDs shown in Table 3 will be described.

(1) Initial Ranging CID

The initial ranging CID indicates a CID used when performing initial ranging, and the initial ranging CID value is "0". Here, the initial ranging is a ranging performed by a base station (BS) to acquire synchronization with a subscriber station, and the initial ranging matches an accurate time and frequency offset between the subscriber station and the base station. , Ranging is performed to adjust the transmit power.

(2) Reentry Ranging CID

The reconnection ranging CID represents a CID used when performing the initial ranging in the reconnection process as the subscriber station successfully acquires synchronization with the base station after initial access with the base station, and loses synchronization with the base station again. The reconnection ranging CID value is "2 ^k ". K is a parameter that can be variably selected according to the system situation.

In general, the subscriber station selects the CIDs allocated before the reconnection process, that is, the basic CID, the same basic CID as the first management CID, and the first management CID. It must be reassigned. In the existing IEEE 802.16e communication system, the base station assigns a unique identifier of the subscriber station, that is, a media access control (MAC) address, during initial ranging according to the reconnection. Check it. The base station checks whether the MAC address of the subscriber station attempting to reconnect is stored in a MAC address list in which MAC addresses of subscriber stations currently registered in the base station are stored. If the check result indicates that the MAC address of the subscriber station is stored in the MAC address list, the base station reassigns the default CID and the first management CID allocated during the initial access to the subscriber station. As a result, the base station must retrieve the MAC address list every initial ranging, and the MAC address list retrieval increases the load of the base station, thus causing a base station connection delay.

Thus, in the present invention, the MAC address list search is performed only for subscriber stations performing initial ranging using the reconnection ranging CID in order to minimize the load of the base station performing the MAC address list search for each initial ranging. Do it. That is, when initial ranging is performed using the initial ranging CID, the base station determines that the subscriber station performing the initial ranging is an initial accessing subscriber station and thus does not search the MAC address list to minimize the base station access delay. It is done. Of course, the base station determines the initial ranging according to the reconnection after the initial access for the subscriber station performing the initial ranging using the reconnection ranging CID, and retrieves the MAC address list to reassign the CIDs allocated during the initial access. To assign.

(3) Hand-Off Ranging CID

The handoff ranging CID indicates a CID used when performing initial ranging to a target base station, that is, a base station to be handed off as the subscriber station hands off. The handoff ranging CID value is “2 ^{k. +1} ".

In general, during the handoff process, the base station to which the current base station belongs, that is, the existing base station, must pass a context managed by the subscriber station to be handed off to the target base station, and the target base station is between the existing base station and the target base station. The context mapping relationship must be informed. That is, as described in the prior art, the target base station notifies the subscriber station of a mapping table indicating which transport CIDs are mapped to the transport CIDs allocated by the existing base station. You must do it. However, when the subscriber station receives a large number of traffics received from the existing base station, since the number of transport CIDs stored in the mapping table is large, the time required for transmitting the mapping table is increased, and thus, when handing off. There was a problem that the access time of the base station is delayed.

Therefore, the present invention proposes the handoff ranging CID so that a base station performs initial ranging by using the handoff ranging CID. To notify the subscriber station and minimize the base station access delay by not considering the context for the subscriber station performing initial ranging without using the handoff ranging CID.

In addition, the handoff ranging CID may be important for the following reasons. The initial ranging according to the handoff should have a higher priority than the initial ranging according to general initial access and reconnection. That is, since the initial ranging according to the handoff is already generated while performing the service, the initial ranging should be performed prior to the initial ranging according to the initial access and reconnection. Since the initial ranging according to the handoff, that is, the initial ranging using the handoff ranging CID, is not the initial ranging according to the reconnection, the MAC address list does not need to be searched. Minimize.

(4) padding CID

The Padding CID represents a CID that is used to indicate the padding, the padding CID value is "2 ¹⁶ - 2 ^k" is. The padding CID is a CID commonly used between the base station and subscriber stations.

(5) basic CID

The default CID represents a CID used when transmitting a message having a relatively short length and urgently transmitted, and the default CID value is "1 to 2 ^k-1 ". For example, as described above, the initial ranging is a ranging performed by the base station to acquire synchronization with the subscriber station, and the base station receives the MAC address of the subscriber station from the subscriber station through the initial ranging procedure. Receive. The base station generates the basic CID by mapping with the received MAC address of the subscriber station.

(6) primary management CID

The first management CID represents a CID used when transmitting a message having a relatively long length and a relatively low urgency, and the first management CID value is "basic CID + 2 ^k ". For example, the base station receives the MAC address of the subscriber station from the subscriber station through the initial ranging procedure, and generates the first management CID together with the basic CID by mapping with the received MAC address of the subscriber station. do.

(7) secondary management CID

The second management CID has a relatively low urgency and indicates a CID used when transmitting a message related to a standard protocol, and the second management CID value is "basic CID + 2 ^{k + 1} ".

(8) transport CID

The transport CID represents a CID used when transmitting data, and the transport CID value is "basic CID + {3 ~ 2 ^16-k -2} 2 ^k ". The transport CID is allocated one by one whenever the subscriber station establishes a connection (hereinafter referred to as a "connection") in order to receive traffic from the base station. Here, the transport CIDs are allocated one by one according to the type of the traffic, and a plurality of transport CIDs are not allocated to the same traffic type. In this case, the connection refers to a connection between MAC peers configured to transmit and receive information, that is, control data and user data, between the subscriber station and the base station. The number and types of connections established between the subscriber station and the base station are plural. Therefore, the identifier for distinguishing the connection established between the subscriber station and the base station is the CID.

(9) multicast polling CID

The multicast polling CID represents a CID that can be used to separate the group to a bandwidth (bandwidth) request, the multicast polling CID value is ^{"2 16 - 2 k +1 ~} 0xFFFE" a. The multicast polling CID is a CID commonly used by all subscriber stations belonging to the base station.

(10) broadcast CID

The broadcast CID indicates a CID used to transmit a broadcast message, and the broadcast CID value is "0xFFFF". In addition, the reserved area of Table 3 has a value of {3 ~ 2 ^16-k -2} 2 ^k .

In Table 3, the CID newly proposed by the present invention is a reconnection ranging CID and a handoff ranging CID. The remaining CIDs, that is, the initial ranging CID, the padding CID, the basic CID, the first management CID, the second management CID, the transport CID, the multicast polling CID, and the broadcast CID, existed previously. CIDs. However, in the present invention, the mapping relationship in which the existing CIDs are mapped to the CIDs newly proposed in the present invention is also newly regulated. Particularly, in the present invention, the relationship between the value of the basic CID and the other CIDs is clearly defined, and if the base station transmits only the basic CID to the subscriber station during initial ranging, the subscriber station does not receive the remaining CIDs from the base station. Even if the subscriber station can calculate the corresponding CID by using the default CID.

Meanwhile, in the IEEE 802.16e communication system, the CID is transmitted through a header area of a MAC-protocol data unit (hereinafter referred to as a "PDU"). Currently, the MAC-PDU of the IEEE 802.16e communication system consists of a MAC header area and a MAC payload area. The CID is transmitted through the MAC header area. In the present invention, the CID is proposed to have a new type of structure, and the CID structure proposed by the present invention will be described with reference to FIG. 7.

7 is a diagram schematically illustrating a CID structure according to an embodiment of the present invention.

Referring to FIG. 7, the CID is divided into a decision part 711 and a basic part 713. The purpose of the CID is determined according to the value of the decision part 711, and the positions of the decision part 711 and the basic part 713 may vary. The basic part 713 determines whether the CID is a CID used for special purposes such as initial ranging, reconnection ranging, handoff ranging, padding, or a CID used to transmit traffic or general MAC messages. Used to distinguish. That is, the basic part 713 is a part for distinguishing whether the CID is a special purpose or a general purpose. If the basic part 713 indicates a specific purpose, the decision part 711 may determine in detail what the purpose is. If the basic part 713 indicates a general purpose, the decision part 711 may further determine what the purpose is. It is part to decide. That is, the specific purpose of the special purpose may be any of initial ranging, reconnection ranging, handoff ranging, or padding, and the specific purpose of the general purpose is to transmit basic message information. Send a primary management message, send a secondary management message, send traffic data, or send a multicast polling message. Or transmitting a broadcast message.

 Next, a process of classifying CIDs using the determination part 711 and the basic part 713 will be described with reference to FIG. 8.

8 is a flowchart illustrating a CID classification process according to an embodiment of the present invention.

Before describing FIG. 8, as described with reference to FIG. 7, the CID has a structure of a decision part and a basic part, and the base station classifies the CID with the decision part and the basic part, that is, uses the CID. Classify First, in step 811, the base station checks whether the basic part of the CID is zero. Here, the basic part of the CID is 0 means that the CID to be determined later is any one of CIDs having a special purpose, that is, an initial ranging CID, a reconnection ranging CID, a handoff ranging CID, and a padding CID. Indicates. If the basic part of the CID is 0, the base station proceeds to step 813. In step 813, the base station determines whether the determination part of the CID is zero. If the determination result of the CID is 0, the base station proceeds to step 815. In step 815, the base station determines the CID as an initial ranging CID and ends.

On the other hand, if the determination part of the CID is not 0 in step 813, the base station proceeds to step 817. In step 817, the base station checks whether the determination part of the CID is one. If the determination result of the CID is 1, the base station proceeds to step 819. In step 819, the base station determines the CID as a reconnection ranging CID and terminates. If the determination result of the CID is not 1 in step 817, the base station proceeds to step 821. In step 821, the base station checks whether the determination part of the CID is two. If the determination result of the CID is 2, the base station proceeds to step 823. In step 823, the base station determines the CID as a handoff ranging CID and ends.

Meanwhile, in step 821, the base station, in which the determination part of the CID is not 2, proceeds to step 825. In step 825, the base station checks whether the determination part of the CID is 2 ^16-k -1. If the determination result of the CID is 2 ^16-k -1, the base station proceeds to step 827. In step 827, the base station determines the CID as a padding CID and ends. In step 825, if the determination part of the CID is not 2 ^16-k − 1, the base station proceeds to step 829. In step 829, the base station determines the CID as an invalid CID and ends.

On the other hand, if the basic part of the CID is not 0 in step 811, the base station proceeds to step 831. Here, the fact that the basic part of the CID is not 0 means that CIDs to be determined later are CIDs having a general purpose, that is, a basic CID, a first management CID, a second management CID, a transport CID, a broadcast CID, Indicates that one of the multicast polling CIDs is a CID. In step 831, the base station determines whether the determination part of the CID is zero. If the determination result of the CID is 0, the base station proceeds to step 833. In step 833, the base station determines the CID as the default CID and ends.

On the other hand, if the determination part of the CID is not 0 in step 831, the base station proceeds to step 835. In step 835, the base station checks whether the determination part of the CID is one. If the determination result of the CID is 1, the base station proceeds to step 837. In step 837, the base station determines the CID as the first management CID and ends. If the determination result of the CID is not 1 in step 835, the base station proceeds to step 839. In step 839, the base station checks whether the determination part of the CID is two. If the determination result of the CID is 2, the base station proceeds to step 841. In step 841, the base station determines the CID as the second management CID and ends.

On the other hand, the base station, if the determination part of the CID is not 2 in step 839 proceeds to step 843. In step 843, the base station checks whether the determination part of the CID is 3 to (2 ^16-k -2). If the determination result of the CID is 3 ~ (2 ^16-k -2), the base station proceeds to step 845. In step 845, the base station determines the CID as a transport CID and ends. If the determination result of the check in step 843 is not 3 ~ (2 ^16-k -2), the base station proceeds to step 847. In step 847, the base station checks whether the determination part of the CID is 2 ^k -1. If the determination result of the CID is 2 ^k -1, the base station proceeds to step 849. In step 849, the base station determines the CID as a broadcast CID and ends. If the determination result of the CID is not 2 ^k -1 in step 847, the base station proceeds to step 851. In step 851, the base station determines the CID as a multicast polling CID and terminates.

Next, a process of classifying the actual CID according to the CID value determination parameter k through the CID classification process will be described with reference to FIG. 9.

9 is a diagram illustrating a CID classification process according to a CID value determination parameter k according to an embodiment of the present invention.

9 illustrates a CID classification process, that is, a CID usage classification process when the CID value determination parameter k is 10 (k = 10). Referring to FIG. 9, when the CID values 0 and 900 correspond to initial ranging CIDs, CID values 1 to 1023 (901) represent basic CIDs and CID values 1024 when corresponding to the CID values described in Table 3 above. 912 indicates a reconnect ranging CID, CID values 1025 to 2047 (902) indicate a first managed CID, CID value 2048 913 indicates a handoff ranging CID, and CID values 2049 to 3071 (903). Represents the second management CID.

In addition, CID values of the region denoted by reference numeral 914 indicate a reserved region, and CID values of the regions denoted by the reference numeral 904 indicate a transport CID. CID value 64512 906 indicates padding CID, CID values 64513 through 65534 905 indicate multicast polling CID, and CID value 65535 907 indicates broadcast CID. In addition, the CID values of the region indicated by reference numeral 908 represent CIDs assigned to the first subscriber station connected to the corresponding base station, and the CID values of the region indicated by reference numeral 909 are allocated to the second subscriber terminal connected to the corresponding base station. CID values of the region indicated by reference numeral 910 indicate CIDs allocated to the 1022 subscriber station accessing the base station, and CID values of the region indicated by reference numeral 911 access the corresponding base station. CIDs allocated to one 1023 subscriber station.

Meanwhile, according to the CID classification process of the present invention as shown in FIG. 9, the relationship between the basic CID, the first management CID, and the CIDs exclusively used by the subscriber station, such as the second management CID and the transport CID, is clear. Appears.

Next, a process of allocating a basic CID among the CIDs will be described with reference to FIG. 10.

10 is a diagram schematically illustrating a process of assigning a basic CID according to an embodiment of the present invention.

Referring to FIG. 10, first, when a base station allocates the basic CID to a subscriber station, the subscriber requests registration on a first ^- come ^-first- served basis within the range of CID values of the basic CID described in Table 3, that is, 1 to 2 ^k-1. Assign to the terminal. For example, as shown in FIG. 10, all of the default CIDs are initially in an unassigned state (1011). When the subscriber station performs the initial ranging and allocates the default CID to the subscriber station, the base station sequentially allocates the default CID (1013 and 1015).

If the subscriber station releases connection to the base station or hands off to another base station due to service termination, the base station no longer needs to maintain the assigned default CID for the subscriber station, and thus the base station Unassigns the assigned default CID. The de-allocated base CID is allocated again to the new subscriber station, that is, to the subscriber station performing the initial ranging again on a first-come, first-served basis (1017).

The basic CID allocation process will now be described in detail.

First, as described above, all of the basic CIDs are initially in an unassigned state (1011). As such, when all basic CIDs exist in an unassigned state and the first subscriber station accesses the base station to the corresponding base station, the base station allocates a basic CID (basic CID = 1) to the first subscriber station (1013). In this case, the first subscriber terminal is assigned only the basic CID, but as described in Table 3, the first management CID and the second management CID associated with the basic CID are in the same state as the assigned state even if they are not separately allocated. . Since the first subscriber terminal has been assigned a basic CID (basic CID = 1), the first management CID (primary management CID = 1025) and the second management CID (secondary management CID = 2049) are allocated according to the association. It is the same.

When the second subscriber station and the third subscriber station, in addition to the first subscriber station, access the base station, the base station allocates a basic CID (basic CID = 2) to the second subscriber station, and the third subscriber station. Allocate a basic CID (basic CID = 3) (1015). In this case, the second subscriber station and the third subscriber station are assigned only the basic CID, but as described in Table 3, the first management CID and the second management CID associated with the basic CID are allocated even though they are not separately allocated. Is in the same state as. That is, since the second subscriber terminal is assigned a basic CID (basic CID = 2), the first management CID (primary management CID = 1026) and the second management CID (secondary management CID = 2050) are allocated according to the association. It is like that. In addition, since the third subscriber terminal has been assigned a basic CID (basic CID = 3), the first management CID (primary management CID = 1027) and the second management CID (secondary management CID = 2051) are allocated according to the association. It is like that.

When the second subscriber station releases the connection with the base station while the first subscriber station to the third subscriber station is assigned a basic CID, the first subscriber station releases the connection with the base station again. The basic CID assigned to the second subscriber terminal (basic CID = 2) and the basic CID assigned to the first subscriber terminal (basic CID = 1) are deallocated (1017). The unassigned basic CIDs are stored to have the next allocation order, that is, the 1021st allocation order and the 1022th allocation order, and are sequentially allocated to other subscriber stations when the allocation order arrives.

In FIG. 10, only the basic CID is described as an example, but the transport CID also has a CID value range of the transport CID, that is, basic CID + traffic in a first-come-first-served manner within a range of {3 to 2 ^16-k -2} 2 ^k. It is assigned to a subscriber station that establishes a connection for the service. In addition, when the subscriber station terminates the service with the base station due to the termination of the service, the connection is released and the base station no longer needs to maintain the assigned transport CID for the subscriber station. The base station deallocates the assigned transport CID. The deassigned transport CID is again assigned on a first-come, first-served basis to a new subscriber station, i.e., to a subscriber station establishing a connection for new traffic.

In Table 3, the CIDs proposed by the present invention have been described. Next, operations in which the CIDs described in Table 3 are actually used will be described.

First, a process of accessing a base station at power-on of a subscriber station will be described with reference to FIG. 11.

FIG. 11 is a signal flowchart schematically illustrating a process of accessing a base station upon initial access according to subscriber station power-on in the IEEE 802.16e communication system according to an embodiment of the present invention.

In FIG. 11, an initial base station access procedure will be described based on a code division multiple access (CDMA) scheme. Referring to FIG. 11, first, a subscriber station 1100 monitors all frequency bands preset in the subscriber station 1100 as it is powered on. ) Detects a pilot channel signal having a Carrier to Interference and Noise Ratio (CINR) (hereinafter referred to as "CINR"). The subscriber station 1100 determines the base station 1150 that has transmitted the pilot channel signal having the strongest pilot CINR as the base station 1150 to which the subscriber station 1100 itself belongs, and the base station 1150. In step 1111, a system receives synchronization with the base station 1150 by receiving a preamble of a downlink frame transmitted by the UE.

As described above, when system synchronization is acquired between the subscriber station 1100 and the base station 1150, the base station 1150 broadcasts base station information related to the base station 1150 to the subscriber station 1100 (1113). step). The base station information includes a Downlink Channel Descriptor (DCD) message, an Uplink Channel Descriptor (UCD) message, and Broadcast through a DL (downlink) -MAP message, an UL (uplink) -MAP message, a neighbor BSs Advertisement (NBR_ADV) message (hereinafter referred to as "NBR_ADV") message, and the like.

The DCD message is a MAC message for broadcasting a downlink burst profile, that is, downlink physical channel information, and the UCD message is a MAC message for broadcasting an uplink burst profile, that is, uplink physical channel information. The DL-MAP message is a MAC message for broadcasting the MAP of the downlink frame, and indicates a location of the downlink frame at which data of the subscriber station exists. In addition, the DL-MAP message includes a PHY (PHYsical) Synchronization set corresponding to a modulation scheme and a demodulation scheme applied to a physical channel to obtain synchronization, and a count corresponding to a configuration change of the DCD message. Is assigned to each of the rangings, a DCD count indicating a base station ID, a base station ID indicating a base station IDentifier, a number of DL-MAP elements n indicating a number of elements existing after the base station ID, Contains information about ranging codes.

The UL-MAP message is a MAC message for broadcasting the MAP of the uplink frame, and indicates a position of the uplink frame at which the data of the subscriber station should be present. In addition, the UL-MAP message may include an Uplink Channel ID indicating an uplink channel ID used, a UCD count indicating a count corresponding to a configuration change of a UCD message, and elements that exist after the UCD count. Number of UL_MAP Elements n indicating the number is included. The NBR_ADV message is a message broadcasted when a subscriber station is handed off and is a broadcast message indicating physical information about neighbor base stations of a base station currently providing a service to the subscriber station. The NBR_ADV message may include N_NEIGHBORS indicating the number of neighbor base stations, a neighbor BS-ID indicating an identifier (ID) of the neighbor base stations, a Configuration Change Count indicating a number of configuration changes, and the neighbor It includes a physical frequency indicating the physical channel frequency of the base station, and other neighbor information (TLV Encoded Neighbor Information) indicating other information related to the neighbor base station in addition to the information.

As such, when the base station 1150 broadcasts base station information about the base station 1150 itself, the subscriber station 1100 receives the broadcast base station information to obtain downlink synchronization with the base station 1150 ( Step 1115). The subscriber station 1100, which has acquired downlink synchronization with the base station 1150, sends a ranging request (RNG-REQ: Ranging-Request) message to the base station 1150 (hereinafter, referred to as "RNG-REQ"). (Step 1117). Here, the RNG-REQ message is a message for requesting the initial ranging, and includes an initial ranging CID and a MAC address of the subscriber station 1100.

The base station 1150 receives the RNG-REQ message from the subscriber station 1100 and maps the MAC address included in the received RNG-REQ message to allocate a default CID to the subscriber station 1100. (Step 1119). Here, conventionally, the base station 1150 checks whether the MAC address of the subscriber station 1100 is registered in the MAC address list of subscriber stations currently registered in the base station 1150, and the subscriber station 1100. If the MAC address is registered in the MAC address list, it is determined that the subscriber station 1100 loses the synchronization and then reconnects after acquiring the synchronization, and the subscriber station 1100 is initially connected according to the reconnection. An operation of reassigning the default CID and the first management CID that was assigned was performed. However, in the present invention, since the CID used for the initial ranging according to the reconnection exists separately as the reconnection ranging CID, the process of searching for the MAC address list managed by the base station 115 is unnecessary. In this way, the MAC address list retrieval process is eliminated, thereby minimizing base station access delay time.

Meanwhile, the base station 1150 registers the MAC address of the subscriber station 1100 included in the RNG-REQ message in the MAC address list, and maps the base CID by mapping the MAC address of the subscriber station 1100. New assignment After the base station 1150 allocates a basic CID to the subscriber station 1100, a ranging response (RNG-RSP: Ranging-Response, hereinafter) is a response message to the RNG-REQ message to the subscriber station 1100. RNG-RSP ") is transmitted (step 1121). Here, the RNG-RSP message includes the allocated basic CID and uplink synchronization information. Upon receiving the RNG-RSP message, the subscriber station 1100 acquires base station uplink synchronization, and completes initial ranging by adjusting frequency and power (step 1123).

After completing the initial ranging, the subscriber station 1100 will call the subscriber station basic capacity negotiation request (SBC-REQ) to the base station 1150 (hereinafter referred to as "SBC-REQ"). In step 1125, the message is transmitted. Here, the SBC-REQ message is a MAC message transmitted by the subscriber station 1100 to negotiate a basic capacity with the base station 1150. The SBC-REQ message can be supported by the subscriber station 1100 in modulation. information on a modulation and coding scheme is included. The base station 1150 receives the SBC-REQ message from the subscriber station 1100, checks the modulation and coding scheme supported by the subscriber station 1100 included in the received SBC-REQ message, and then the As a response message to the SBC-REQ message, a basic capacity negotiation response (SBC-RES: Subscriber Station's Basic Capability Negotiation Response, hereinafter referred to as "SBC-RES") message is transmitted (step 1127).

By receiving the SBC-RES message, the subscriber station 1100 completes the basic capacity negotiation of the subscriber station 1100 (step 1129), and requests an encryption key management request to the base station 1150 (PKM-REQ: Privacy). Key Management Request, hereinafter referred to as "PKM-REQ" message (step 1131). Here, the PKM-REQ message is a MAC message for subscriber station authentication and includes unique information of the subscriber station 1100. The base station 1150 receiving the PKM-REQ message performs authentication with an authentication server (AS) with the unique information of the subscriber station 1100 included in the PKM-REQ. If the subscriber station 1100 is an authenticated subscriber station as a result of the authentication, the base station 1150 transmits an encryption key management response (PKM-RES) to the subscriber station 1100 as a response message to the PKM-REQ message. Management response, hereinafter referred to as " PKM-RES ") (step 1133). In this case, the PKM-RES message includes an authentication key (AK) assigned to the subscriber station 1100 and a traffic encryption key (TEK).

By receiving the PKM-RES message, the subscriber station 1100 completes authentication of the subscriber station 1100 and simultaneously acquires an encryption key (step 1135), and requests registration with the base station 1150 (REG-). REQ: Registration Request, hereinafter referred to as "REG-REQ") (step 1137). Here, the REG-REQ message includes subscriber station registration information of the subscriber station 1100. Upon receiving the REG-REQ message, the base station 1150 detects subscriber station registration information included in the REG-REQ message and registers the subscriber station 1100 with the base station 1150.

The base station 1150, which has registered the subscriber station, sends a registration response (REG-RES) message, which is a response message to the REG-REQ message, to the subscriber station 1100. Transmit (step 1139). Here, the registered REG-RES message includes the registered subscriber station registration information. In the related art, when the REG-REQ message is received, the base station should allocate a second management CID for the corresponding subscriber station. However, as described above, in the present invention, when the base station notifies the subscriber station only of the basic CID, the subscriber station performs each process. Since the corresponding CID can be identified, the base station does not need to separately allocate and notify the second management CID.

By receiving the REG-RES message, the subscriber station 1100 completes registration of the subscriber station 1100 itself (step 1141). As such, when the registration of the subscriber station is completed, the subscriber station 1100 is assigned a basic CID from the base station 1150, and the subscriber station 1100 itself and the second management CID correspond to the basic CID. Management CIDs can be assigned and identified. After the subscriber station 1100 completes registration of the subscriber station with the base station 1150, an Internet Protocol (IP) connection is established between the subscriber station 1100 and the base station 1150, and the connected Internet protocol is established. Operation information is downloaded (download) through (step 1143). Thereafter, a service flow is connected between the subscriber station 1100 and the base station 1150 (step 1145). Here, the service flow refers to a flow in which the MAC-SDU is transmitted and received through a connection having an arbitrary Quality of Service (QoS). As described above, since the transport CID must be allocated in transmitting and receiving the MAC-SDU, that is, the traffic, the subscriber station 1100 is assigned a transport CID when the service flow is connected. Here, the transport CID has a value of basic CID + {3 ~ 2 ^16-k -2} 2 ^k as described in Table 3 above. In this way, when the service flow is connected, the service is actually performed between the subscriber station 1100 and the base station 1150 (step 1147).

In FIG. 11, a process of accessing a base station during initial access according to power-on of a subscriber station has been described. Secondly, a process of accessing a base station when a subscriber station loses synchronization after initial access and reconnects with reference to FIG. 12 will be described.

12 is a signal flow diagram schematically illustrating a base station access procedure when a subscriber station reconnects in an IEEE 802.16e communication system according to an embodiment of the present invention.

Referring to FIG. 12, first, since the subscriber station 1200 loses synchronization after initial connection with the current base station, the base station 1250 that the subscriber station 1200 belongs to identifies. That is, a system synchronization is obtained between the subscriber station 1200 and the base station 1250, and the base station 1250 broadcasts base station information related to the base station 1250 to the subscriber station 1200 (1211). step). The base station information is broadcasted through a DCD message, a UCD message, a DL-MAP message, a UL-MAP message, an NBR_ADV message, and the like as described with reference to FIG. 11.

As such, when the base station 1250 broadcasts base station information on the base station 1250 itself, the subscriber station 1200 receives the broadcast base station information to obtain downlink synchronization with the base station 1250 ( Step 1213). In this way, the subscriber station 1200 having downlink synchronization with the base station 1250 transmits an RNG-REQ message to the base station 1250 (step 1215). Here, the RNG-REQ message includes a reconnection ranging CID and a MAC address of the subscriber station 1200.

The base station 1250 receives the RNG-REQ message from the subscriber station 1200, and the MAC address included in the received RNG-REQ message exists in the MAC address list managed by the base station 1250. Check if it is. If the MAC address of the subscriber station 1200 exists in the MAC address list as a result of the check, the base station 1250 reallocates the default CID allocated to the subscriber station 1200 at initial access (step 1217). Here, the base station 1250 detects that the REG-REQ message is an initial ranging due to reconnection since the REG-REQ message includes a reconnection ranging CID. Accordingly, the base station 1250 searches for a MAC address list managed by the base station 1250 and performs initial access. It is to reallocate the default CID assigned to the subscriber station (1200). That is, in the present invention, since the MAC address list is searched only when initial ranging is performed using the reconnection ranging CID, unnecessary time consumption due to the MAC address list search is eliminated.

Meanwhile, the base station 1250 reassigns the default CID to the subscriber station 1200 and transmits an RNG-RSP message to the subscriber station 1200 (step 1219). Here, the RNG-RSP message includes the reassigned basic CID and uplink synchronization information. Upon receiving the RNG-RSP message, the subscriber station 1200 acquires base station uplink synchronization and adjusts frequency and power to complete initial ranging (step 1221).

In this way, after completing the initial ranging, the subscriber station 1200 transmits an SBC-REQ message to the base station 1250 (step 1223). Here, the SBC-REQ message includes information on the modulation and coding scheme that the subscriber station 1200 can support. The base station 1250 receives the SBC-REQ message from the subscriber station 1200, checks the modulation and coding schemes that the subscriber station 1200 can include in the received SBC-REQ message, and then checks the SBC-REQ message. Send a RES message (step 1225).

By receiving the SBC-RES message, the subscriber station 1200 completes the basic capacity negotiation of the subscriber station 1200 (step 1227) and transmits a PKM-REQ message to the base station 1250 (step 1229). ). Here, the PKM-REQ message includes the unique information of the subscriber station 1200. The base station 1250 receiving the PKM-REQ message performs authentication with an authentication server with the unique information of the subscriber station 1200 included in the PKM-REQ. If the subscriber station 1200 is an authenticated subscriber station as a result of the authentication, the base station 1250 transmits a PKM-RES message to the subscriber station 1200 (step 1231). Here, the PKM-RES message includes an authentication key assigned to the subscriber station 1200 and an encryption key.

By receiving the PKM-RES message, the subscriber station 1200 acquires an encryption key at the same time as completing the authentication of the subscriber station 1200 itself (step 1233), and sends a REG-REQ message to the base station 1250. Transmit (step 1235). Here, the REG-REQ message includes subscriber station registration information of the subscriber station 1200. The base station 1250 receiving the REG-REQ message detects subscriber station registration information included in the REG-REQ message and registers the subscriber station 1200 with the base station 1250.

The base station 1250 registering the subscriber station transmits a REG-RES message to the subscriber station 1200 (step 1237). Here, the registered REG-RES message includes the registered subscriber station registration information. In the related art, when the REG-REQ message is received, the base station should allocate a second management CID for the corresponding subscriber station. However, as described above, in the present invention, when the base station notifies the subscriber station only of the basic CID, the subscriber station performs each process. Since the corresponding CID can be identified, the base station does not need to separately allocate and notify the second management CID.

By receiving the REG-RES message, the subscriber station 1200 completes registration of the subscriber station 1200 itself (step 1239). When the subscriber station registration is completed, the subscriber station 1200 is reassigned a basic CID from the base station 1250, and the subscriber station 1200 itself is the first management CID corresponding to the reassigned basic CID. And, it is possible to assign and identify the second management CID. After the subscriber station 1200 completes registration of the subscriber station with the base station 1250, an internet protocol connection is established between the subscriber station 1200 and the base station 1250, and operation information is downloaded through the connected internet protocol. (Step 1241). Thereafter, a service flow is connected between the subscriber station 1200 and the base station 1250 (step 1243). Here, when the service flow is connected, the subscriber station 1200 is assigned a transport CID, and the transport CID is a value of basic CID + {3 ~ 2 ^16-k -2} 2 ^k as described in Table 3 above. Has When the service flow is connected, the service is actually performed between the subscriber station 1200 and the base station 1250 (step 1245).

12 illustrates a base station access process when a subscriber station loses synchronization after initial access and reconnects. Third, a process of accessing a base station during handoff by a subscriber station will be described with reference to FIG.

13 is a signal flow diagram schematically illustrating a base station access procedure when handing off a subscriber station in an IEEE 802.16e communication system according to an embodiment of the present invention.

Referring to FIG. 13, as described above with reference to FIG. 12, even when a service is performed between the subscriber station 1200 and the base station 1250 (step 1311), the base station 1250 periodically broadcasts base station information (1313). step). When the subscriber station 1200 that has received base station information broadcast by the base station 1250 detects that the handset needs to be handed off, the subscriber station 1200 handoffs among neighboring base stations included in the NBR_ADV message of the base station information. A base station to determine to determine (step 1315). After determining the base station to be handed off, the subscriber station 1200 notifies that the base station 1250 is to be handed off, that is, to an existing base station (step 1217).

Thereafter, the subscriber station 1200 performs a series of processes for continuously performing the service with the base station 1350 that is determined to handoff, that is, the target base station 1350. The base station 1350 broadcasts base station information related to the base station 1350 to the subscriber station 1200 in step 1319. The base station information is broadcasted through a DCD message, a UCD message, a DL-MAP message, a UL-MAP message, an NBR_ADV message, and the like as described with reference to FIGS. 11 and 12.

As such, when the base station 1350 broadcasts base station information about the base station 1350 itself, the subscriber station 1200 receives the broadcast base station information to obtain downlink synchronization with the base station 1350 ( Step 1321). The subscriber station 1200 having the downlink synchronization with the base station 1350 transmits an RNG-REQ message to the base station 1350 (step 1323). Here, the RNG-REQ message includes a handoff ranging CID and a MAC address of the subscriber station 1200.

The base station 1350 receives the RNG-REQ message from the subscriber station 1200, and the handoff ranging CID is included in the received RNG-REQ message. Recognize that it is initial ranging. Since the base station 1350 recognizes that the subscriber station 1200 is handed off, the base station 1350 maps with the MAC address included in the received RNG-REQ message to allocate a default CID to the subscriber station 1200 ( Step 1325). When the subscriber station 1250 hands off, the base station 1350 does not need to search the MAC address list managed by the base station 1350 itself, thereby minimizing the base station access delay time due to the MAC address list search. .

Meanwhile, the base station 1350 allocates a basic CID to the subscriber station 1200 and transmits an RNG-RSP message to the subscriber station 1200 (step 1327). Here, the RNG-RSP message includes the allocated basic CID and uplink synchronization information. Upon receiving the RNG-RSP message, the subscriber station 1200 acquires base station uplink synchronization, and completes initial ranging by adjusting frequency and power (step 1329).

In this way, after completing the initial ranging, the subscriber station 1200 transmits an SBC-REQ message to the base station 1350 (step 1331). Here, the SBC-REQ message includes information on the modulation and coding scheme that the subscriber station 1200 can support. The base station 1350 receives the SBC-REQ message from the subscriber station 1200, checks the modulation and coding scheme supported by the subscriber station 1300 included in the received SBC-REQ message, and then SBC. Send a -RES message (step 1333).

By receiving the SBC-RES message, the subscriber station 1200 completes the basic capacity negotiation of the subscriber station 1200 (step 1335) and transmits a PKM-REQ message to the base station 1350 (step 1337). ). Here, the PKM-REQ message includes the unique information of the subscriber station 1200. The base station 1350 receiving the PKM-REQ message performs authentication with an authentication server with the unique information of the subscriber station 1200 included in the PKM-REQ. If the subscriber station 1200 is an authenticated subscriber station as a result of the authentication, the base station 1350 transmits a PKM-RES message to the subscriber station 1200 (step 1339). Here, the PKM-RES message includes an authentication key assigned to the subscriber station 1200 and an encryption key.

By receiving the PKM-RES message, the subscriber station 1200 completes authentication of the subscriber station 1200 itself and simultaneously acquires an encryption key (step 1341), and sends a REG-REQ message to the base station 1350. Transmit (step 1343). Here, the REG-REQ message includes subscriber station registration information of the subscriber station 1200. Upon receiving the REG-REQ message, the base station 1350 detects subscriber station registration information included in the REG-REQ message and registers the subscriber station 1200 with the base station 1350.

The base station 1350 registering the subscriber station transmits a REG-RES message to the subscriber station 1200 (step 1345). Here, the registered REG-RES message includes the registered subscriber station registration information. In the related art, as the base station 1350 receives the REG-REQ message, the base station 1350 allocates a second management CID for the subscriber station 1200, and also the CIDs allocated by the existing base station, that is, the base station 1250; A mapping table indicating a mapping relationship between CIDs allocated by the base station 1350 was generated, and the generated second management CID and the mapping table were included in the REG-RES message and transmitted. However, in the present invention, the delay time according to the mapping table transmission is eliminated by removing the second management CID and the mapping table transmission.

Meanwhile, the subscriber station 1200 completes registration of the subscriber station 1200 itself by receiving the REG-RES message (step 1347). As such, when the subscriber station registration is completed, the subscriber station 1200 is allocated with a base CID from the base station 1350, and the subscriber station 1200 itself with a first management CID corresponding to the allocated base CID; The second management CID can be assigned and identified. After the subscriber station 1200 completes registration of the subscriber station with the base station 1350, an internet protocol connection is established between the subscriber station 1200 and the base station 1350, and operation information is downloaded through the connected internet protocol. (Step 1349).

Next, an internal structure of a CID allocation device for performing a function in an embodiment of the present invention will be described with reference to FIG. 14.

14 is a block diagram showing an internal structure of a CID allocation device for performing a function in an embodiment of the present invention.

Referring to FIG. 14, first, the controller 1411 may have a 'k' value for distinguishing between a decision part constituting a CID and a basic part, and the basic part may be special according to the type of CID to be generated. If the basic part is a special purpose or a general purpose, the decision part outputs information indicating the purpose of each detailed purpose to the CID generator 1413. Here, since the detailed purposes for each of the special purpose and the general purpose are the same as those described with reference to FIG. 7, the detailed description thereof will be omitted.

The CID generator 1413 generates a CID by inputting information output from the controller 1411. Here, if the information output from the controller 1411 is a default CID, the CID generator 1413 generates a default CID in the order of the default CID allocation stored in the default CID allocation management table 1415 and the default CID. The basic CID allocation management table 1415 is updated according to the allocation. Here, since the basic CID generation order and update process of the basic CID allocation management table 1415 are the same as those described with reference to FIG. 10, a detailed description thereof will be omitted.

Also, if the information output from the controller 1411 is a transport CID, the CID generator 1413 may include a transport CID allocation management table, that is, a transport CID allocation management table 1419-1 to a transport CID allocation management table ( 1419-N) generates a transport CID in the order of transport CID allocation and stores the default CID allocation management table according to the transport CID generation. Here, since the transport CID generation order and update process of the transport CID allocation management table are the same as described above with reference to FIG. 10, a detailed description thereof will be omitted.

In addition, the CID generator 1413, if the information output from the controller 1411 is a common purpose CID, that is, all other than the CID dedicated to the subscriber station, such as the initial ranging CID, multicast polling CID, etc. In the case of a CID shared to subscriber stations, a CID is generated by referring to a predetermined CID with reference to the common purpose CID allocation table 1417. On the other hand, the CID generator 1413 generates a corresponding CID is composed of a decision part and a basic part as described in FIG.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by the equivalents of the claims.

As described above, the present invention has an advantage in that CIDs for distinguishing a connection between a base station and a subscriber station can be allocated to have a correlation therebetween in a broadband wireless access communication system. In addition, the present invention is to be assigned to have a correlation between the CIDs so as to recognize the base station and the subscriber station even if the CIDs do not transmit and receive separately, to eliminate the signaling overhead due to the transmission and reception of the CID and at the same time eliminates the redundancy due to the transmission and reception of the CID Has the advantage. In addition, the present invention allows the base station to perform the initial ranging in accordance with the state of the subscriber station by allocating a CID to classify the initial ranging according to the state of the subscriber station, that is, the initial connection, reconnection, and handoff. This has the advantage of minimizing base station access delays.

1 is a diagram schematically showing a general IEEE 802.16a communication system

2 is a diagram schematically showing a general IEEE 802.16e communication system

3 is a diagram schematically illustrating a MAC-PDU structure of a general IEEE 802.16e communication system.

4 is a signal flow diagram schematically illustrating a process of accessing a base station when a subscriber station is powered on and reconnected after initial access in a general IEEE 802.16e communication system.

5 is a signal flow diagram schematically illustrating a process of accessing a base station during handoff of a subscriber station in a general IEEE 802.16e communication system

6 is a diagram schematically illustrating a CID classification process according to a CID value determination parameter in a general IEEE 802.16e communication system.

7 schematically illustrates a CID structure according to an embodiment of the present invention.

8 is a flowchart illustrating a CID classification process according to an embodiment of the present invention.

9 is a diagram schematically illustrating a CID classification process according to a CID value determination parameter k according to an embodiment of the present invention.

10 is a diagram schematically illustrating a process of assigning a basic CID according to an embodiment of the present invention.

11 is a signal flow diagram schematically illustrating a process of accessing a base station upon initial access according to subscriber station power-on in the IEEE 802.16e communication system according to an embodiment of the present invention.

12 is a signal flow diagram schematically illustrating a base station access procedure when a subscriber station reconnects in an IEEE 802.16e communication system according to an embodiment of the present invention.

13 is a signal flow diagram schematically illustrating a process of accessing a base station during handoff of a subscriber station in an IEEE 802.16e communication system according to an embodiment of the present invention.

14 is a block diagram showing an internal structure of a CID allocation device for performing a function in an embodiment of the present invention.

Claims (49)

A method of allocating a connection identifier in a broadband wireless access communication system, Detecting the type of connection identifier to be allocated, detecting a type of connection identifier to be allocated; After detecting the type of the connection identifier, the connection identifier is assigned to have information indicating the type according to a combination of information included in the first part and the second part and the information contained in the first part and the second part. The method comprising the step of. The method of claim 1, And the first part includes information indicating whether the type of the connection identifier is a type of a first predetermined type. A method of allocating a connection identifier in a broadband wireless access communication system, Detecting all kinds that the connection identifier may have; After detecting all types of the connection identifier, information having the first part and the second part for each of the all types, and indicating the type according to a combination of information included in the first part and the second part; And assigning the connection identifier to have a connection identifier. The method of claim 3, And the first part includes information indicating whether the type of the connection identifier is a type of a first predetermined type. The method of claim 4, wherein The types of connection identifiers may include an initial ranging connection identifier, a reconnection ranging connection identifier, a handoff ranging connection identifier, a padding connection identifier, a basic connection identifier, a first management connection identifier, and a second management connection identifier. And a transport connection identifier, a multicast polling connection identifier and a broadcast connection identifier. The method of claim 5, The first type of connection identifier types include the ranging connection identifier, the reconnection ranging connection identifier, the handoff ranging connection identifier, and the padding connection identifier. The method of claim 5, When the first part includes information indicating that the type of the connection identifier is the type of the first type, the second part includes the ranging identifier as the ranging connection identifier, the reconnection ranging connection identifier, and the handoff. And information indicating which type of connection identifier corresponds to a ranging connection identifier and a padding connection identifier. The method of claim 5, When the first part includes information indicating that the type of the connection identifier is not the type of the first type, the second part includes the connection identifier as the basic connection identifier, the first management connection identifier, and the first part. And 2) information indicating which kind of connection identifier corresponds to a management connection identifier, a transport connection identifier, a multicast polling connection identifier, and a broadcast connection identifier. A method of allocating a connection identifier in a broadband wireless access communication system, A subscriber station requesting ranging to an eNB including an initial ranging connection identifier and a medium access control address; The base station detecting the ranging request includes assigning a basic connection identifier corresponding to the medium access control address, and responding to the ranging request to the subscriber station including the basic connection identifier and uplink synchronization information. The method characterized in that. The method of claim 9, When the subscriber station detects a response to the ranging request, the subscriber station including registration information of the subscriber station and requesting registration from the base station; The base station detecting the registration request further includes the step of registering the subscriber station, and responding to the registration request including the registered subscriber station registration information. The method of claim 9, The subscriber terminal further comprises the step of generating other connection identifiers other than the basic connection identifier in accordance with a preset configuration rule with the basic connection identifier. The method of claim 11, The other connection identifiers may be a first management connection identifier, a second management connection identifier and a transport connection identifier, and the first management connection identifier, the second management connection identifier and the transport connection identifier may each correspond to the default connection identifier value. The method as claimed in claim 1, wherein the method is generated by adding a preset value. The method of claim 9, Wherein the initial ranging connection identifier is a connection identifier used when the ranging request is a ranging request according to an initial base station access of the subscriber station. A method of allocating a connection identifier in a broadband wireless access communication system, A subscriber station requesting ranging to a base station including a reconnection ranging connection identifier and a medium access control address; Detecting the ranging request, searching for a list of medium access control addresses managed by the base station, and detecting a basic connection identifier already assigned to the ranging requesting subscriber station; The base station reassigns the detected basic connection identifier to a basic connection identifier of the subscriber station, and responds to the ranging request to the subscriber station including the reassigned basic connection identifier and uplink synchronization information. Said method comprising: a. The method of claim 14, When the subscriber station detects a response to the ranging request, the subscriber station including registration information of the subscriber station and requesting registration from the base station; The base station detecting the registration request further includes the step of registering the subscriber station, and responding to the registration request including the registered subscriber station registration information. The method of claim 14, The subscriber terminal further comprises the step of generating other connection identifiers other than the basic connection identifier in accordance with a preset configuration rule with the basic connection identifier. The method of claim 16, The other connection identifiers may be a first management connection identifier, a second management connection identifier and a transport connection identifier, and the first management connection identifier, the second management connection identifier and the transport connection identifier may each correspond to the default connection identifier value. The method as claimed in claim 1, wherein the method is generated by adding a preset value. The method of claim 14, And the reconnection ranging connection identifier is a connection identifier used when the ranging request is a ranging request according to base station reconnection of the subscriber station. A method of allocating a connection identifier in a broadband wireless access communication system, If the subscriber station receiving the service from the first base station determines to handoff to a second base station different from the first base station, ranging to the second base station includes a handoff ranging connection identifier and a medium access control address. The process of requiring, The second base station detecting the ranging request allocates a basic connection identifier corresponding to the medium access control address and responds to the ranging request to the subscriber station including the basic connection identifier and uplink synchronization information. The method characterized in that it comprises a. The method of claim 19, When the subscriber station detects a response to the ranging request, the subscriber station including registration information of the subscriber station and requesting registration from the base station; The base station detecting the registration request further includes the step of registering the subscriber station, and responding to the registration request including the registered subscriber station registration information. The method of claim 19, The subscriber terminal further comprises the step of generating other connection identifiers other than the basic connection identifier in accordance with a preset configuration rule with the basic connection identifier. The method of claim 21, The other connection identifiers may be a first management connection identifier, a second management connection identifier and a transport connection identifier, and the first management connection identifier, the second management connection identifier and the transport connection identifier may each correspond to the default connection identifier value. The method as claimed in claim 1, wherein the method is generated by adding a preset value. The method of claim 19, And the handoff ranging connection identifier is a connection identifier used when the ranging request is a ranging request according to a handoff of the subscriber station. An apparatus for allocating a connection identifier in a broadband wireless access communication system, A controller for detecting a type of connection identifier to be allocated and controlling to generate the connection identifier according to the detected type when detecting that the connection identifier should be allocated; A connection identifier generator for generating the connection identifier having the first part and the second part under the control of the controller and having the information indicating the type according to a combination of the information included in the first part and the second part. The device characterized in that it comprises a. The method of claim 24, And the first part includes information indicating whether the type of the connection identifier is a type of a first predetermined type. An apparatus for allocating a connection identifier in a broadband wireless access communication system, A controller for detecting all kinds of connection identifiers and generating the connection identifiers corresponding to each of the detected kinds; Generate the connection identifiers such that the connection identifier has a first part and a second part under the control of the controller, and has the information indicating the type according to a combination of information included in the first part and the second part. And a connection identifier generator. The method of claim 26, And the first part includes information indicating whether the type of the connection identifier is a type of a first predetermined type. The method of claim 27, The types of connection identifiers may include an initial ranging connection identifier, a reconnection ranging connection identifier, a handoff ranging connection identifier, a padding connection identifier, a basic connection identifier, a first management connection identifier, and a second management connection identifier. And a transport connection identifier, a multicast polling connection identifier and a broadcast connection identifier. The method of claim 28, And the first type of connection identifier types include the ranging connection identifier, the reconnection ranging connection identifier, the handoff ranging connection identifier, and the padding connection identifier. The method of claim 28, When the first part includes information indicating that the type of the connection identifier is the type of the first type, the second part includes the ranging identifier as the ranging connection identifier, the reconnection ranging connection identifier, and the handoff. And a device indicating information corresponding to a kind of a ranging connection identifier and a padding connection identifier. The method of claim 28, When the first part includes information indicating that the type of the connection identifier is not the type of the first type, the second part includes the connection identifier as the basic connection identifier, the first management connection identifier, and the first part. And 2) information indicating which kind of connection identifier corresponds to a management connection identifier, a transport connection identifier, a multicast polling connection identifier, and a broadcast connection identifier. An apparatus for allocating a connection identifier in a broadband wireless access communication system, A subscriber station requesting ranging to the base station including an initial ranging connection identifier and a medium access control address; And the base station assigning a basic connection identifier corresponding to the medium access control address according to the ranging request, and responding to the ranging request to the subscriber station, including the basic connection identifier and uplink synchronization information. Said device. 33. The method of claim 32, The subscriber station, upon detecting a response to the ranging request, requests registration to the base station including registration information of the subscriber station itself. The method of claim 33, wherein And when the base station detects the registration request, registers the subscriber station and then responds to the registration request to the subscriber station, including the registered subscriber station registration information. 33. The method of claim 32, And the subscriber station generates other connection identifiers except for the basic connection identifier according to a preset setting rule with the basic connection identifier. 36. The method of claim 35 wherein The other connection identifiers may be a first management connection identifier, a second management connection identifier and a transport connection identifier, and the first management connection identifier, the second management connection identifier and the transport connection identifier may each correspond to the default connection identifier value. The apparatus as claimed in claim 1, wherein the device is generated by adding a preset value. 33. The method of claim 32, And the initial ranging connection identifier is a connection identifier used when the ranging request is a ranging request according to an initial base station connection of the subscriber station. An apparatus for allocating a connection identifier in a broadband wireless access communication system, A subscriber station requesting ranging to the base station, including a reconnection ranging connection identifier and a medium access control address; Search for a list of media access control addresses managed by the base station according to the ranging request, and reassign a basic connection identifier already assigned to the ranging requesting subscriber station as a basic connection identifier of the subscriber station; And the base station responding to the ranging request to the subscriber station, including the reassigned basic connection identifier and uplink synchronization information. The method of claim 38, The subscriber station, upon detecting a response to the ranging request, requests registration to the base station including registration information of the subscriber station itself. The method of claim 39, And when the base station detects the registration request, registers the subscriber station and then responds to the registration request to the subscriber station, including the registered subscriber station registration information. The method of claim 38, And the subscriber station generates other connection identifiers except for the basic connection identifier according to a preset setting rule with the basic connection identifier. The method of claim 41, wherein The other connection identifiers may be a first management connection identifier, a second management connection identifier and a transport connection identifier, and the first management connection identifier, the second management connection identifier and the transport connection identifier may each correspond to the default connection identifier value. The apparatus as claimed in claim 1, wherein the device is generated by adding a preset value. The method of claim 38, And the reconnection ranging connection identifier is a connection identifier used when the ranging request is a ranging request according to base station reconnection of the subscriber station. An apparatus for allocating a connection identifier in a broadband wireless access communication system, When receiving the service from the first base station, if it is determined that the handoff should be performed to a second base station different from the first base station, the second base station requests ranging by including a handoff ranging connection identifier and a medium access control address. Subscriber terminal, And a second base station for allocating a basic connection identifier corresponding to a medium access control address according to the ranging request and responding to the ranging request to the subscriber station including the basic connection identifier and uplink synchronization information. The device, characterized in that. The method of claim 44, The subscriber station, upon detecting a response to the ranging request, requests registration to the base station including registration information of the subscriber station itself. The method of claim 45, And when the base station detects the registration request, registers the subscriber station and then responds to the registration request to the subscriber station, including the registered subscriber station registration information. The method of claim 44, And the subscriber station generates other connection identifiers except for the basic connection identifier according to a preset setting rule with the basic connection identifier. The method of claim 47, The other connection identifiers may be a first management connection identifier, a second management connection identifier and a transport connection identifier, and the first management connection identifier, the second management connection identifier and the transport connection identifier may each correspond to the default connection identifier value. The apparatus as claimed in claim 1, wherein the device is generated by adding a preset value. The method of claim 44, And the handoff ranging connection identifier is a connection identifier used when the ranging request is a ranging request according to a handoff of the subscriber station.