KR100417733B1 - the control method of Internet Protocol micro-mobility with handoff state mode - Google Patents

Abstract

Disclosed is an IP micro mobility communication method having a hand off state mode for efficiently supporting local, that is, micro mobility when a handoff occurs in a wireless mobile access network. In the present invention, since the paging routing cache is configured to enable the location tracking of the mobile host at all nodes in the access network, fast and accurate paging is possible as in the cellular system, and high-speed routing of newly received data packets is possible. . In particular, when performing routing for the first received data packet from the Internet, the control packet or the broadcasting of the data packet is unnecessary, so that the traffic load in the access network is greatly reduced. In addition, the introduction of a semi-soft handoff mechanism reduces the handoff delay and traffic load in the access network, and has the advantage of quickly recognizing and changing the operation mode of the mobile host and the time of change between the old and new base stations. In addition, the configuration and operation method is simpler than the conventional communication node, and the processing time in the node is shortened by searching only one paging routing cache, thereby reducing the transmission delay. In particular, as the number of mobile hosts increases, it has better performance characteristics.

Description

IP control method with the handoff state mode {the control method of Internet Protocol micro-mobility with handoff state mode}

The present invention relates to an Internet protocol (IP) micro mobility communication method having a handoff state mode, and particularly when handoff occurs in a wireless mobile access network. The present invention relates to an IP micro-mobility communication method having a handoff state mode for supporting a network.

In general, as the Internet service is rapidly developed in the wireless mobile network, the network structure is composed of a global Internet service that performs mobile IP as shown in FIG. 1 and a cellular cell configured to accommodate an increasing number of wireless users. It will consist of the Internet.

Hierarchical Mobile IP (HMIP) has been studied as an IP micro mobility management technology for supporting local mobility in an access network having a wireless cellular network type.

The cellular IP communication method is relatively excellent in micro mobility in an access network, but it is difficult to perform high-speed location tracking for each mobile host due to the location tracking function of a paging area unit. In addition, Paging Cache (PC) and Routing Cache (RC) are used to manage paging and route in the access network, respectively. Paging Cache is selectively used only for a specific node. The use of a cache requires the broadcasting of packets, which results in a complicated cache management in the node and a large number of duplicated control packets, which further increases the traffic load in the access network.

On the other hand, the semisoft handoff mechanism under consideration in the cellular IP communication method ensures that the mobile host can continue to receive packets immediately after the handoff.

However, when a mobile host moves to a new base station (BS), the new and old mappings coexist in the cache of the nearest cross node (CoN: Crossover Node) during the route timeout, so that the cross nodes and both base stations There is a disadvantage in that the load in the access network is increased due to the redundant data traffic transmitted between the mobile network, the mobile host has a problem that the packet may be duplicated or lost if the timing of the packet received from both base stations are off.

The present invention has been invented to solve the above problems, and the IP micro mobility communication method having the handoff state mode according to the present invention is a handset when the route update time period for an active mobile host is too long in a cellular IP communication method. If the amount of data packets transmitted through the previous path at the time of off increases, many of these packets are lost or redundantly delivered. If the period is too short, the amount of control packets (i.e. signaling) in the network is increased to increase the traffic load. The quasisoft handoff mechanism is proposed to improve the shortcomings that have a significant effect, and operate an additional handoff state mode in the mobile host, and distinguish between the handoff state mode, the active state mode, and the idle state mode. In the status mode and idle state mode, a long cycle of update packets and a handoff state mode To provide an IP Micro-mobility communications method only has a short period handoff mode for transmitting a packet of update it is an object.

In addition, in the conventional cellular IP communication method, since paging for idle mobile hosts is managed only by a specific node in the access network, a node without a paging cache broadcasts the packet to all downlinks in the node for routing when receiving data packets from the outside. By casting, the number of paging packets or data packets in the access network is exploded, and when the size of the access network is large, this time becomes longer, so that the handoff state mode according to the present invention is improved in order to improve the disadvantage that it is impossible to transmit traffic requiring real time. The IP micro mobility communication method has a paging cache and a routing cache that are used to manage paging and route in the access network as a paging routing cache (PRC), and are configured to operate in all nodes in the access network. Hand off status mode To provide an IP communication method having a micro mobility it is an object.

1 is a network structure diagram illustrating global mobility and local mobility in a communication method according to the present invention.

FIG. 2 is a structural diagram of a mobile access network to which micro mobility is applied in FIG. 1.

3 is an operation diagram of an in-network paging routing cache for showing a communication method according to the present invention.

4 is a flowchart illustrating a semi-soft handoff mechanism in a communication method according to the present invention.

5 is a mobile host state mode operation state transition diagram of the communication method according to the present invention.

6 is a block diagram of a mobile host configuration of the communication method according to the present invention.

7 is a flowchart illustrating an operation of an idle state mode in a mobile host according to the present invention.

8 is a flowchart illustrating an operation in an active state mode of a mobile host in a communication method according to the present invention.

9 is a flowchart illustrating an operation of a handoff state mode in a mobile host according to the present invention.

10 is a block diagram illustrating a routing node in a communication method according to the present invention.

11 is a flowchart illustrating an uplink routing operation in a routing node in a communication method according to the present invention.

12 is a flowchart illustrating a downlink routing operation in a routing node in a communication method according to the present invention.

<Explanation of symbols for the main parts of the drawings>

1: Internet 2: Access Network

3: home agent 4: gateway

5: node 6: mobile host

7: cross node 8: cell area

9: Paging Routing Cache 10: Idle State Mode

11: active state mode 12: handoff state mode

The present invention for achieving such an object,

In an access network 2 having the Internet 1 as a backbone and composed of a plurality of base station nodes 5 such as a base station, a router, and a gateway, to which a plurality of mobile hosts 6 can be connected,

When the mobile host 6 has an idle state mode 10, it is used for high-speed location management. When the mobile host 6 has an active state mode 11 and a handoff state mode 12, routing is performed. Configure a paging routing cache 9 on the node 5 to be used for the purpose,

For the mobile host 6 having the idle mode and the active state mode, the paging route update packet is transmitted at the paging route update time interval in which the mobility time interval is a relatively long period, thereby updating the paging routing cache 9, and the handoff state. For the mobile host 6 having a mode, the paging routing cache 9 is updated by transmitting handoff state packets at handoff state update time intervals in which packet transmission intervals are relatively short.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 illustrates an example of a network structure that describes global mobility and local (micro) mobility, and hierarchical mobility management schemes are roughly classified into local mobility and global mobility. Local mobility is also referred to as micromobility and deals with frequent movement between base stations in the same access network 2, such as a local area network (LAN). This local mobility can be roughly divided into two types, one having a hierarchical foreign agent (FA) under the gateway (4) and a regional tunnel between the gateway (4) and the external agent. The other method is to configure and maintain mobile host (6) -based routing of the corresponding base station node (5) for mobility management in the access network (2).

The former Internet Expert Task Force (IETF) draft is HMIP, and the latter is cellular IP and HAWAII. On the other hand, global mobility in the Internet 1 deals with mobility with low frequency of movement between access networks 2 including communication with the home agent 3, and generally uses the existing mobile IP as it is.

2 is an example of a structure of a mobile access network 2 to which micro mobility is applied, and a gateway 4 and a base station node 5 are added to the network. Here, the gateway 4 performs the function of interconnecting the Internet backbone 1 and the access network 2, and the base station node 5 is located in the access network 2 and operates at the network level, the router 7 or May be a base station 5. Here, the base station node 5 is responsible for its cell area 8 and performs a communication function with the mobile host 6 in the cell area 8 through a wireless interface.

3 is an operation diagram of the integrated paging routing cache 9 in the network according to the present invention, between the state mode of the mobile host 6 and the paging routing cache 9 in the base station node 5 in the communication method according to the present invention. Interaction relationship is shown.

In the cellular IP communication method, two paging caches and two routing caches are used, and in the communication method according to the present invention, all of the base station nodes 5 have a paging routing cache, whereas the paging cache is limited to only a specific base station node 5. (9) It is composed of only one. Therefore, the operation of the paging routing cache 9 has a different purpose and operation depending on the operation state of the mobile host (6). That is, it is used for high speed location management for the mobile host 6a having the idle state and for routing purpose for the mobile host 6b having the active and handoff states. Also, for the idle and active mobile hosts 6, a paging route update packet is transmitted at a paging route update time interval, which is a relatively long period of mobility time interval, to update the paging routing cache 9, but to the handoff mobile host 6 For example, the handoff state packet is transmitted at the handoff state update time interval, which is a relatively short period of the packet transmission interval, to update the paging routing cache 9.

Table 1 describes the operation of the routing cache in the base station node 5 of the communication method according to the present invention. In the present invention, by using the integrated paging routing cache (9), it is possible to reduce the traffic load in the access network (2) and increase the bandwidth, and to easily manage the memory (cache) in the base station node (5), memory capacity and packet processing The time will be greatly reduced. In addition, since all the base station nodes 5 perform the paging function, high-speed paging is possible, so that future real-time multimedia services may be easily accommodated.

<Table 1> Operation of paging routing cache

Fig. 4 is an operation flowchart of a semi-soft handoff mechanism, which recognizes that the handoff is started when the mobile host 6 receives a beacon signal from the new base station 5a, and immediately paging to the previous base station 5n. After the route update packet is drawn, the handoff status packet is transmitted to the new base station 5a, and the reception status is returned to the previous base station 5n again to continue receiving the data packet until the previous path termination packet is received.

The closest cross node (7) of the mobile host (6) receiving the handoff status packet unmaps the previous path in the paging routing cache (9), which integrates and stores paging and route information, and Set up the mapping. Subsequently, the previous path termination packet is transmitted to the previous path, and the data packet received after the handoff is transmitted to the new path. When the mobile host 6 receives the previous path termination packet from the previous path, the mobile host 6 disconnects from the previous base station 5n and receives the data packet that is delivered after the handoff toward the new base station 5a.

The purpose of the mobile host 6 to transmit the paging route update packet to the previous base station 5n immediately after the handoff occurs is to cross the previous base station 5n until the handoff state packet arrives at the cross node 7. This is to regenerate the mapping in the associated base station node 5 so that the path to the node 7 does not time out, thereby preventing packet loss during transmission. In addition, the cross-node 7 receiving the handoff state packet terminates the mapping to the old base station 5n and generates a mapping to the new base station 5a, which subsequently receives packets arriving at the cross-node 7. This is to suppress duplicated traffic in the access network 2 by transmitting only to the new base station 5a. On the other hand, the previous path termination packet is used for the mobile host 6 to clearly indicate the switching point from the old base station 5n to the new base station 5a, whereby the handoff state can be terminated quickly.

5 is a transition diagram of the mobile host 6 state mode operation state of the present invention. In addition to the idle state mode 10 and the active state mode 11, the handoff state mode 12 is separately added to the mobile host 6. Operated. The basic operation procedure in the idle state mode 10 and the active state mode 11 is the same as in the conventional cellular IP communication method, but in the communication method according to the present invention, the mobile host 6 is in the access network 2. In order to provide route information, the paging route update packet is transmitted in the paging route update time period for the active state mode 11 and the idle state mode 10 separately from the handoff state mode 12. Here, the paging route update time period is used as the paging update time of the cellular IP communication method.

However, each time the active mobile host 6 transmits a data packet, the paging route update packet timer is reset, and the next paging route update packet is transmitted after the paging route update time.

In addition, the handoff state mode 12 is switched every time the mobile host 6 moves to a new base station node 5, depending on the state before the mobile host 6 is switched to the handoff state mode 12. Separate actions were performed. That is, when the previous state is the idle state mode 10, it is necessary to perform the real-time location management function, the mobile host 6 receives the beacon signal from the new base station node 5, the handoff state mode 12 The switch returns to the idle state mode 10 after transferring the handoff state packet to the new base station node 5 immediately.

On the other hand, when the previous state is the active mode 11, the handoff function should be performed quickly without loss of data. Therefore, when the mobile host 6 receives the beacon signal from the new base station node 5, the handoff is performed. Transitioning to the state mode 12 immediately transfers the handoff state packet to the new base station node 5 and resumes receiving data packets from the previous base station node 5 again.

At this time, the mobile host 6 transmits the handoff state packet to the new base station node 5 at a period equal to the route update time of the cellular IP communication method as a period shorter than the paging route update packet transmission interval in order to process the handoff quickly. And the data packet reception from the previous base station node (5). Data packets generated at the mobile host 6 during handoff are forwarded only through the new base station node 5. This process continues until the mobile host 6 receives the previous path termination packet from the previous base station node 5, and when this control packet is received, the mobile host 6 immediately enters the active mode 11. It returns and switches reception to the new base station node 5.

FIG. 6 is a block diagram illustrating a mobile host 6 according to the present invention. The handoff controller 13 determines whether a handoff is generated according to the measured beacon signal strength, and determines a radio frequency setting and a route corresponding to an IP address. Change and maintain. The protocol state machine 16 manages three states such as an idle state mode 10, an active state mode 11, and a handoff state mode 12, and performs data packet transmission and reception functions according to each state mode. In addition, it controls the timer operation according to the timeout set for each status mode. The control packet generator 14 monitors the data packets being transmitted, and in the absence of these packets, the paging route update packet in the idle state mode 10 and the active state mode 11 according to the operation mode state, and the handoff state. In mode 12, handoff status packets are periodically generated and transmitted. The data packet generator 15 generates a data packet to be transmitted to the base station node 5.

7 is an operation flowchart of the idle state mode 10 in the mobile host 6 of the present invention, which forwards a paging route update packet (17) and waits for reception of a data packet (step 18). Whether the mobile host 6 moves to the active mode 11 according to the reception of the data packet, or whether the mobile host 6 is moved through the reception of the beacon signal from the new base station node 5 while in the idle state 10. Check (step 19) to switch to the handoff state mode 12.

8 is an operation flowchart of the active state mode 11 in the mobile host 6 of the present invention. When the active state mode 11 is reached, after receiving a data packet and starting an active state timer (step 20), the mobile host (6) checks whether there is a data packet to transmit (step 21). If there is a data packet to be transmitted, the data packet is forwarded (step 22), and if there is no more data packet to be transmitted or if the active timer has timed out (step 23), the idle state mode if the data packet has been transmitted or timed out Switch to 10, otherwise check whether a beacon signal has been received from the new base station node 5 (step 24). If a beacon signal has been received, a handoff state has occurred during the transmission of the data packet, and immediately switches to handoff state mode 12. However, in step 21, if there is no data packet to be transmitted by the mobile host 6, it checks whether the paging route update timeout (step 25), and transmits the paging route update packet at the paging route update time period (step 26).

9 is an operation flowchart of the handoff state mode 12 in the mobile host 6 of the present invention, which is activated whenever the mobile host 6 moves to a new base station node 5. When the state before the transition is the idle state mode 10, the mobile host 6 receives the beacon signal from the new base station node 5, switches to the handoff state mode 12, and immediately transfers the handoff state packet to the new state. After the transfer to the base station, the process returns to the idle state immediately (step 33). On the other hand, if the previous state is the active state mode 11, the mobile host 6 receives the beacon signal from the new base station node 5, the handoff state mode 12 is activated immediately the previous base station node (5) Transmits the paging route update packet (step 27) and transmits the handoff status packet to the new base station (step 28), and then turns back to the previous base station node (5) to receive and activate the data packet. Start the timer (step 29). Thereafter, the mobile host 6 checks whether there is a data packet to transmit (step 30), if there is a data packet to transmit, transmits the data packet to the new base station node 5 (step 31), and the previous path termination packet is received. The data packet continues to be received until step 32 (step 32), and when this control packet is received, the mobile host 6 immediately returns to the active state mode 11. However, if there is no data packet to be transmitted to the mobile host 6 in step 30, the handoff state timeout is checked (step 34). When the timeout occurs, the handoff state packet is transmitted to the new base station node 5 (step 34). Step 35) The function is again performed from step 32. If the timeout is not performed in step 34, the function is immediately performed from step 32.

10 is a block diagram of the routing nodes 5 and 7 of the present invention, wherein the paging route update function block 36 keeps the paging and route information updated for all uplink packets in the paging routing cache 9. , Unmap timed out. The paging route lookup functional block 37 interprets the downlink data packet and searches the paging routing cache 9 for mappings related to the destination mobile host 6. The forwarding engine functional block 38 sends downlink packets to the interface selected by the paging routing cache 9 mapping.

The base station node 5 in the communication method according to the present invention has a simpler configuration and operation method than the base station node 5 in the cellular IP communication method, and also searches for only one paging routing cache 9 so that the base station node ( The processing time in 5) can be shortened and the transmission delay can be reduced.

FIG. 11 is a flowchart illustrating the uplink routing operation in the routing nodes 5 and 7 of the present invention. When a packet is received in the uplink (step 39), it is checked whether it is a data packet (step 40). 9) after resetting the 'SA = IFP_c' mapping timer (step 43), the packet is forwarded to the uplink interface mapped to the paging routing cache 9 (step 44). However, if it is not a data packet in step 40, it is checked whether there is an SA mapping in the paging routing cache 9 (step 41), and if it does not exist, generating a 'SA = IFP_c' mapping in the paging routing cache 9. Continue from 47. If there is an SA mapping in step 41, the current port is compared with the previous port to which the packet was input (step 42).

That is, by checking whether 'IFP_p = IFP_c' (step 42), if it is not the same, it corresponds to the cross node (7) when a handoff occurs. In this case, after transmitting the previous path termination packet to the previous path ( Step 45) The previous mapping 'SA = IFP_p' in the paging routing cache 9 is released (step 46), and the process continues from the step of creating a new 'SA = IFP_c' mapping (step 47).

On the other hand, if it is the same in step 42 and checks whether 'IFP_p = IFP_c', it corresponds to the general base station node 5 in which no handoff has occurred. In this case, the process continues from step 43.

Where SA is the source address, IFP is the interface port on which the packet arrived, IFP_p is the previous IFP, and IFP_c is the current IFP.

Fig. 12 is a flowchart of the downlink routing operation in the routing nodes 5 and 7 of the present invention. When a packet is received in the downlink (step 48), the presence of DA mapping in the paging routing cache 9 is checked ( Step 49). If the mapping does not exist, the received packet is discarded (step 50). If the mapping exists, the packet is forwarded to the downlink interface mapped in the paging routing cache 9 (step 51). Where DA represents the destination address.

Table 2 below compares the features of the conventional cellular IP communication method (CIP) and the communication method (ECIP) of the present invention. In the cellular IP communication method, a control packet such as a paging update packet in the case of the idle mobile host 6 and a root update packet in the case of the active mobile host 6 is used. In case of all hosts 6, only one paging route update packet is used.

In addition, in the cellular IP communication method, a paging update packet of a relatively long period is transmitted as a mobility generation period to a new base station node 5, and a route update packet is transmitted at a data packet transmission interval of a relatively short period. However, in the communication method according to the present invention, the paging route update packet is transmitted at the same paging route update time period as the paging update packet of the CIP communication method. Therefore, the traffic load by these control packets used for routing and paging in the access network 2 is significantly lower than that of the CIP communication method.

In addition, in the ECIP communication method, in order to deal with this promptly when a handoff occurs, the mobile host 6 having the handoff transmits the handoff state packet at the same handoff state update time period as the root update time of the CIP communication method. . In general, since handoff does not occur frequently, the degree to which the handoff state packet affects the load of the access network 2 is very small. In addition, by repeatedly transmitting a handoff state packet in a short period immediately after a handoff occurs, and rapidly changing the downlink from the cross node 7 to the new base station node 5, the handoff delay is reduced as well as the access network 2 Since duplicate packets in the network are not generated, the traffic load in the access network 2 is significantly reduced compared to the CIP communication method.

On the other hand, in the communication method according to the present invention, since the paging routing cache 9 is configured to enable the location tracking of the mobile host 6 to all nodes (base stations, routers, gateways, etc.) 5 in the access network 2. As with cellular systems, fast and accurate paging is possible, and high-speed routing of newly received initial data packets is possible. In particular, when performing the routing for the first received data packet from the Internet 1, traffic in the access network 2 is reduced because the control packet or broadcasting of the data packet is unnecessary. However, in the CIP communication method, an unnecessary traffic increase is caused by broadcasting data packets in all downlinks for routing in the base station node 5 having no paging cache. As described above, in the ECIP communication method, there is an improvement effect such as reducing traffic in the Internet 1 and an access network 2, and fast data reception by high-speed paging and routing.

<Table 2> Comparison of features of CIP communication method and ECIP communication method of the present invention

Table 3 below compares the characteristics of the semi-soft handoff mechanism used in the conventional CIP communication method and the semi-soft handoff mechanism used in the ECIP communication method of the present invention. The most influential factor is the handoff mechanism. In the case of the semi-soft handoff mechanism, the data packet generated in the mobile host 6 during the handoff is transmitted through the new base station node 5, and the data packet sent from the counterpart host 6 is transmitted to the previous base station node ( Receive through 5). On the other hand, in the case of the semi-soft handoff mechanism, the data packet generated at the mobile host 6 during the handoff is transmitted through both base station nodes 5, and the data packet sent from the counterpart host 6 is transmitted to the previous base station node. Received through (5). As a result, in the semi-soft handoff mechanism, the packets generated from the mobile host 6 are duplicated, resulting in an increase in traffic in the access network 2, and an increase in the handoff delay.

<Table 3> Feature comparison between semi-soft handoff mechanism and semi-soft handoff mechanism

There are a few other features. First, when using the semi-soft handoff mechanism, after the handoff, the new mapping and the old mapping coexist in the cache until the previous path is rooted out. The forwarded data packets are duplicated in the new and old paths, resulting in unnecessary traffic increase in the access network 2. In order to improve this, the semi-soft handoff mechanism can quickly construct a new path to the cross node 7 by forwarding the handoff status packet to the new path as soon as the handoff occurs, and also the cross node 7 As soon as this packet is received at the s), by un-mapping the old path in the cross node 7 and setting the mapping for the new path, the data packet to the mobile host 6 is no longer forwarded to the old path. It was not. Second, when using the semi-soft handoff mechanism, the mobile host 6 receives the data packet from the previous base station node 5 during the root timeout of the previous path and recognizes its termination, thereby ending the handoff state. As a result, packet loss and duplication may occur, and operation control of the mobile host 6 may be complicated, and the timing of switching from the old path to the new path may be incorrect. In order to improve this, the semi-soft handoff mechanism uses the previous path termination packet to accurately recognize the timing of the transition from the old path to the new path after the handoff, thereby preventing the loss of data packets. ) Can be controlled easily. Third, the semisoft handoff delay may be any value between the root timeout of the previous path after the mobile host 6 sends the semisoft root update packet to the new base station node 5. On the other hand, the semi-soft handoff delay is until the mobile host 6 receives the previous path termination packet from the previous base station node 5 after transmitting the handoff status packet to the new base station node 5. The semisoft handoff delay is therefore shorter than the semisoft handoff delay.

On the other hand, in order to examine the performance characteristics of the present invention, the amount of packets in the access network (2) due to the handoff according to the change of the mobile host (6) and the route update time and the existing CIP communication method and ECIP communication Comparing the methods is shown in <Table 4>. Here, the environment used to consider the performance characteristics is that the size of the route update packet and the handoff state packet is 100 bytes, the transmission rate of the route update packet is 30% and the paging update time when there is no transmission data in the mobile host 6 One minute, the arrival rate of the received packet is 200 bytes / second, the handoff occurrence period is 10 minutes, the handoff duration is 10 seconds, the ratio of the root update time and the root timeout is 3, and the test duration is 100 minutes. .

Table 4 Amount of packets in the access network 2 due to handoff due to changes in the mobile host 6 and the route update time [Unit: Mbits]

As shown in Table 4, it can be seen that in the ECIP communication method, the traffic in the access network 2 is significantly lower than the CIP communication method. In particular, in both the ECIP communication method and the CIP communication method, as the number of mobile hosts 6 increases, the amount of packets increases, but the degree is much larger in the CIP communication method. In addition, the smaller the value of the route update time, the larger the packet quantity, and the CIP communication method is more affected. The reason is that the smaller the value, the more the control packet due to the frequent route update. Because it becomes. From the above results, it can be seen that the ECIP communication method is superior to the CIP communication method.

Next, when the number of mobile hosts 6 and the transmission rate of route update packets when there is no transmission data in the mobile host 6 change, route update packets, paging update packets, and handoffs in the access network 2 change. The total amount of control packets such as status packets is compared with the existing CIP communication method and the ECIP communication method of the present invention. The environment used to examine the performance characteristics is the size of the route update packet, paging control packet and handoff state packet is 100 bytes, the route update time is 1 second, the paging update time is 1 minute, the number of paging areas is 10, The number of cell regions 8 in the paging area is 10, the handoff occurrence period is 10 minutes, the handoff duration is 10 seconds, and the test duration is 100 minutes.

<Table 5> Amount of total control packets in the access network 2 when the number of mobile hosts and the transmission rate of the route update packet when there is no transmission data in the mobile host 6 change [Unit: Mbits]

As shown in Table 5, the traffic in the access network 2 increases in proportion to the mobile host 6. In the ECIP communication method, the traffic of the entire control packet in the access network 2 is reduced compared to the CIP communication method. It can be seen that it is significantly lower. In particular, when the transmission rate of the route update packet when there is no transmission data in the mobile host 6, there is almost no change in the ECIP communication method, but rapidly increases in proportion to this value in the CIP communication method. This result is because the ECIP communication method is hardly influenced by the operation mode of the mobile host 6 in the access network 2, and therefore, it can be seen that the ECIP communication method is superior to the CIP communication method.

As described above, the ECIP communication method according to the present invention uses the paging routing cache 9 to enable the location tracking of the mobile host 6 in all base station nodes 5 in the access network 2 as compared with the CIP communication method. As such, as in a cellular system, fast and accurate paging is possible, and high-speed routing of newly received data packets is possible. In particular, when performing routing for the first received data packet from the Internet 1, the traffic load in the access network 2 is greatly reduced since no broadcasting of the control packet or data packet is necessary. In addition, the introduction of a semi-soft handoff mechanism reduces handoff delay and traffic load in the access network (2), and quickly changes the operation mode of the mobile host (6) and the change point between the old and new base station nodes (5). There is an advantage that can be done by recognition. In addition, the base station node 5 of the ECIP communication method has a simpler configuration and operation method than the base station node 5 of the CIP communication method, and the processing time in the base station node 5 by searching only one paging routing cache 9. This shortens the transmission delay. In particular, the ECIP communication method has better performance characteristics than the CIP communication method as the number of mobile hosts 6 increases.

Although the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited thereto and may be improved or modified by those skilled in the art within the scope of the technical idea of the present invention.

Claims (6)

In an access network 2 having the Internet 1 as a backbone and composed of a plurality of base station nodes 5 such as a base station, a router, and a gateway, to which a plurality of mobile hosts 6 can be connected, When the mobile host 6 has an idle state mode 10, it is used for high-speed location management. When the mobile host 6 has an active state mode 11 and a handoff state mode 12, routing is performed. Configure the paging routing cache (9) to all the base station nodes (5) to be used for the purpose, For the mobile host 6 having the idle mode and the active state mode, the paging route update packet is transmitted at the paging route update time interval in which the mobility time interval is a relatively long period, thereby updating the paging routing cache 9, and the handoff state. For the mobile host 6 having a mode, the handoff state mode is updated by transmitting handoff state packets at handoff state update time intervals in which packet transmission intervals are relatively short. IP micro mobility communication method with 2. The mobile host (6) according to claim 1, wherein the mobile host (6) transmits a paging route update packet at a paging route update time period in an active state mode (11) and an idle state mode (10), and the mobile host (6) transmits a data packet. And resetting the paging route update packet timer each time so that the next paging route update packet is transmitted after the paging route update time. The handoff controller function block according to claim 1, wherein the mobile host (6) determines whether a handoff is generated according to the measured beacon signal strength, and changes or maintains a route corresponding to a radio frequency setting and an IP address. (13); The idle state mode 10, the active state mode 11, and the handoff state mode 12 are managed, and the data packet is transmitted and received according to each state mode, and the timeout set for each state mode is also performed. A protocol state machine function block 16 for controlling a timer operation according to the same; Monitors the data packets being transmitted, and if these packets are not present, according to the operation mode state, the paging route update packet is selected in the idle state mode 10 and the active state mode 11, and the handoff is performed in the handoff state mode 12. A control packet generator function block 14 for periodically generating and transmitting a status packet; And a data packet generator function block (15) for generating a data packet for transmission to the base station node (5). 4. The protocol state machine function block (16) according to claim 3, wherein the protocol state machine functional block (16) delivers a paging route update packet when the mobile host (6) is in the idle state mode (10), and activates the mobile host when a data packet is received. Mode 11, and when a beacon signal is received from the new base station node 5, checking whether the mobile host 6 moves or not and performing the operation of switching to the handoff state mode 12. IP micro mobility communication method having a handoff state mode (12). 4. The protocol state machine function block (16) according to claim 3, wherein the protocol state machine function block (16) starts the active state timer after the data packet is received when the mobile host (6) is in the active state mode (11). Checking whether there is a data packet to transmit; Transmitting a data packet when there is a data packet to be transmitted in the step, and checking whether there is no data packet to be transmitted or whether the active state timer has timed out; Transitioning to idle state mode (10) if the data packet has been transmitted or timed out after the step; otherwise, checking whether a beacon signal has been received from the new base station node (5); If the beacon signal is received in this step, it is recognized that the handoff state is generated during the transmission of the data packet, and immediately switches to the handoff state mode 12. If the mobile host 6 has no data packet to transmit, the paging route update time IP micro mobility communication method having a handoff state mode (12), characterized in that the step of transmitting a paging route update packet at a paging route update time period by checking whether or not it is out. In an access network (2) composed of a plurality of base station nodes (5) such as a base station, a router, a gateway, and the like, in which the Internet 1 is a backbone, and to which a plurality of mobile hosts 6 can be connected, When the mobile host 6 receives a beacon signal from the new node 5, it recognizes that the handoff is started, and immediately transfers a paging route update packet to the old node 5 and a handoff state to the new base station node 5. Transmitting a packet; After the above step, the receiver returns to the previous base station node 5 so as to continuously receive the data packet until the previous path termination packet is received, and the closest cross node 7 of the mobile host 6 that has received the handoff state packet. C) disabling the mapping of the old path in the paging routing cache 9 which integrates and stores the paging and the root information and sets the mapping of the new path; And, After the step, the previous path transmits the previous path termination packet, the new path transmits the data packet received after the handoff, and when the mobile host 6 receives the previous path termination packet from the previous path, Receiving the data packet that has been delivered after the handoff towards the new base station node (5) and disconnecting the old base station node (5).