WO2019030983A1

WO2019030983A1 - Session control device

Info

Publication number: WO2019030983A1
Application number: PCT/JP2018/015543
Authority: WO
Inventors: 陽平片山; アナラゾリーグ; 賢二福井; 榑林　亮介; 滋岩科
Original assignee: 株式会社Ｎｔｔドコモ
Priority date: 2017-08-08
Filing date: 2018-04-13
Publication date: 2019-02-14
Also published as: JPWO2019030983A1

Abstract

The present invention addresses the problem of achieving more reliable session migration. This session control device 1 serves to control a session constituted by a logical communication path established between a base station 4b and a gateway device 5 in a network 8. When the session control device 1 determines that migration of a relay operation performed by relay function 2a currently relaying the session to relay function 2b currently not relaying the session would result in the session path after migration being shorter than that before migration, the session control device 1: transmits an instruction to relay function 2a to transmit information about the session currently relayed by relay function 2a to relay function 2b; and transmits an instruction to the base station 4b and the gateway device 5 to migrate the relay operation from relay function 2a to relay function 2b.

Description

Session controller

The present invention relates to a session control apparatus that controls a session that is a logical communication path established between nodes in a network.

In the mobile communication network of Non-Patent Document 1 below, logical communication linked with a terminal (UE; User Equipment) between a base station (eNodeB) and a gateway device (PDN-GW; Packet Data Network-Gateway) A session, which is a path, is created, and the terminal communicates with the destination outside the mobile communication network via the session. The session is created and controlled by the control system of the mobile communication network according to the control signal from the terminal. The session may be relayed by the relay function. The relay function is, for example, SGW (Serving Gateway) in Non-Patent Document 1 below, but, for example, as a virtual node (VNF; Virtual Network Function) dynamically by further using the network virtualization technology of Non-Patent Document 2 below. It can be created and activated. This allows the number to be processed (scaled out) to handle more sessions.

In the mobile communication network as described above, when the relay by the existing relay function relaying the session is shifted to the relay by the newly activated relay function, the session path may be shortened. However, even in such a case, a mechanism for reliably transitioning the relay by the existing relay function to the relay by the newly activated relay function is not considered.

Therefore, it is an object of the present invention to provide a session control apparatus capable of more reliably transitioning a session in order to solve the above problems.

In order to solve the problems described above, a session control device according to an aspect of the present invention is a session control device that controls a session that is a logical communication path established between nodes in a network, and is a session control device. When the relay by the first relay function, which is the relaying function, is shifted to the relay by the second relay function, which is the function that does not relay the session, the session path after the transition is shorter than before the transition. If it is determined that the first relay function transmits to the first relay function an instruction to cause the second relay function to transmit information on the session relaying the first relay function, the relay by the first relay function of the session is relayed by the second relay function Send an instruction to the node to shift to

According to such a session control device, when it is determined that the path of the session becomes shorter after transition compared to before transition when the relay by the first relay function is shifted to the relay by the second relay function, the first relay function An instruction is sent to the first relay function to cause the second relay function to transmit information on the session that the relay is relaying. Since the said information is transmitted to a 2nd relay function by this, a 2nd relay function can relay reliably after transfer. Further, an instruction to shift relay by the first relay function of the session to relay by the second relay function is transmitted to the node. Thus, the session established between nodes in the network can be reliably transferred from relay by the first relay function to relay by the second relay function. That is, the session can be transferred more reliably.

You can migrate sessions more reliably.

It is a figure explaining the change of the session when a relay function is added to the system by a prior art. It is a figure explaining the change of the session when a relay function is added to the session control system containing the session control apparatus which concerns on embodiment of this invention. It is a functional block diagram of a session control device concerning an embodiment of the present invention. It is a figure which shows the example of a table of a topology management table. It is a figure which shows the example of a table of the shortest path | route table | surface. It is a figure which shows the example of a table of a session management table. It is a figure which shows the example of a table of a session transfer destination table. It is a sequence diagram which shows control processing of the session control system containing the session control apparatus which concerns on embodiment of this invention. It is a figure explaining the hardware constitutions of the session control apparatus concerning the embodiment of the present invention.

Hereinafter, an embodiment of a session control device will be described in detail with reference to the drawings. In the description of the drawings, the same elements will be denoted by the same reference symbols, without redundant description. Further, the embodiments in the following description are specific examples of the present invention, and unless otherwise stated, the present invention is not limited to these embodiments.

First, using FIG. 1 and FIG. 2, the change of the session when the relay function is added to each of the system according to the prior art and the session control system 9 including the session control device 1 according to the embodiment of the present invention. Explain the differences.

FIG. 1 is a diagram for explaining a change in session when a relay function is added to a system according to the prior art. FIG. 1 (a) shows a prior art system before the relay function is added. As shown in FIG. 1A, the system according to the prior art includes a relay function (relay function A etc. is generically called a relay function), a terminal, a base station (base station A, base station B etc. as a base). And a gateway device, a destination, and a transfer device (generally called transfer device A and transfer device B etc. are called transfer devices). The relay function, the base station, the gateway device, and the transfer device are functions or nodes that constitute a mobile communication network. Here, the function is, for example, a software function that performs predetermined processing, and is implemented in a node or the like. The node is, for example, a computer device. Hereinafter, for the sake of convenience, “function or node” is generically referred to as “node”.

The terminal, the base station and the gateway device are respectively common devices of the same name included in the mobile communication network. For example, in the 3GPP standard or its equivalent or derivative, the terminal is a UE, the base station is an eNodeB, and the gateway apparatus is a PDN-GW. The destination is a computer apparatus or the like with which the terminal communicates, and exists in an external network outside the mobile communication network. The forwarding device is a node that forwards communications in the mobile communication network. The relay function is a function of relaying communication in the mobile communication network, and is, for example, SGW.

As shown in FIG. 1A, in a mobile communication network, a plurality of base stations (including a base station A), a transfer apparatus A, a plurality of base stations (including a base station B), a transfer apparatus B, a transfer apparatus A The transfer device B, the transfer device A and the relay function A, and the transfer device B and the gateway device can communicate with each other by wired connection or the like. Further, outside the mobile communication network, the terminal and the base station B can communicate with each other by wireless connection and the like, and the gateway device and the destination can communicate with each other by wire connection and the like.

In the state shown in FIG. 1 (a), as indicated by the arrows in the figure, the terminal, base station B, transfer device B, transfer device A, relay function A, transfer device A, transfer device B, transfer device B, gateway device, and Sessions (communication paths) are established (created) in series in the order of destination and in reverse order. Hereinafter, the session is described as “terminal-base station B-transfer device B-transfer device A-relay function A-transfer device A-transfer device B-gateway device-destination”. Here, a session is a logical communication path established between a specific terminal, a node in a mobile communication system, and an external network, and, for example, “Packet Data Protocol” described in Non-Patent Document 3 GPP TS 29.060 "Context" or "Multimedia Broadcast / Multicast Service Context". The session is tied to the terminal. The terminal communicates with the destination via a session associated with the terminal.

Here, it is assumed that the relay function in the mobile communication network can be dynamically created and activated as a virtual node by using, for example, the network virtualization technology of Non-Patent Document 2 described above. In the system according to the prior art shown in FIG. 1 (b), in the system shown in FIG. 1 (a), the relay function B is newly dynamically created and activated, and communicates with the transfer device B by wire connection etc. Indicates the state of possible connection. That is, the state shown in FIG. 1 (b) is a state scaled out from the state shown in FIG. 1 (a). As shown in FIG. 1 (b), there is no change in (the path of) the session even in the state of being scaled out.

In the state shown in FIG. 1 (b), in the mobile communication network, when the relay by the existing relay function A relaying the session is shifted to the relay by the newly activated relay function B, the path of the session Becomes shorter. However, even in such a case, a mechanism for reliably transitioning the relay by the existing relay function A to the relay by the newly started relay function B is not considered in the prior art. More specifically, in the prior art, when scaled out and when the relay function has a state of being associated with a session, a new relay function is activated to a place where the path is shorter than seen from a certain terminal. Even if it does, communication can not be performed via the relay function anew until the terminal is retouched. Since the rear touch of the terminal does not occur frequently, communication occurs over a long time until the rear touch occurs, resulting in unnecessary communication.

FIG. 2 is a diagram for explaining the change of the session when the relay function is added to the session control system 9. FIG. 2A shows the session control system 9 before the relay function is added. As shown in FIG. 2A, the session control system 9 includes a session control device 1, a relay function 2 (collectively called the relay function 2a etc. as the relay function 2), a terminal 3, a base station 4 (base station 4a and Base station 4b etc. generically called base station 4), gateway device 5, destination 6, and transfer device 7 (generally called transfer device 7a and transfer device 7b etc. transfer device 7) Ru. The session control device 1, the relay function 2, the base station 4, the gateway device 5, and the transfer device 7 are nodes constituting a network 8 which is a mobile communication network.

The session control device 1 is a computer device that controls a session established between nodes in a mobile communication network. Details of the session control device 1 will be described later. The relay function 2, the terminal 3, the base station 4, the gateway 5, the destination 6, and the transfer device 7 are the same as those of the same names described in FIG. Further, the session established in the state shown in FIG. 2A is also the same as that described in FIG. The session control device 1 can be connected to nodes such as the relay function 2 in the network 8, the base station 4, the gateway device 5, and the transfer device 7 via the network 8.

In the session control system 9 shown in FIG. 2A, the relay function 2b is newly created dynamically and activated in the session control system 9 in the state shown in FIG. Indicates the state of being communicably connected. That is, the state shown in FIG. 2 (b) is a state scaled out from the state shown in FIG. 2 (a). As shown in FIG. 2 (b), in the state of being scaled out, (the path of) the session is changed. Specifically, in the state shown in FIG. 2B, as indicated by the arrow in the figure, the session is “terminal 3-base station 4b-transfer device 7b-relay function 2b-transfer device 7b-gateway device 5- It has changed to become the destination 6 ". That is, the relay by the existing relay function 2a (first relay function) is shifted to the relay by the newly activated relay function 2b (second relay function). The transition is performed by the session control device 1 at the time of scale-out as described later. As apparent from comparison between FIG. 2 (a) and FIG. 2 (b), the path of the session after transition is shorter than before the transition. As described above, in the session control system 9, the session can be more reliably transferred to the relay function 2 in which the route is immediately shortened according to the scale-out of the relay function 2.

FIG. 3 is a functional block diagram of the session control device 1. As shown in FIG. 3, the session control device 1 includes the topology management table storage unit 10, the shortest route table storage unit 11, the session management table storage unit 12, the activation detection unit 13, the route calculation unit 14, the transition preparation instruction unit 15, and the state. A synchronization instruction unit 16, a transition instruction unit 17, and a session information deletion instruction unit 18 are included. Hereinafter, each functional block of the session control device 1 shown in FIG. 3 will be described.

The topology management table storage unit 10 stores a topology management table that manages the topology (network topology) of the network 8. FIG. 4 is a diagram showing an example of a topology management table. Specifically, FIG. 4 (a) is a diagram showing an example of a table of a topology management table showing the topology of the network 8 shown in FIG. 2 (a). FIG. 4 (b) is a diagram showing an example of a table of a topology management table showing the topology of the network 8 shown in FIG. 2 (b). For example, in the example of the table shown in FIG. 4A, the first record indicates that the base station 4a and the transfer device 7a are connected via a network. The other records are similar. The topology management table stored by the topology management table storage unit 10 is updated according to the existing technology by a node or the like in the network 8 including the session control device 1 when the topology changes or at any timing.

The shortest path table storage unit 11 stores the shortest path table indicating the shortest path between the nodes in the network 8. FIG. 5 is a diagram showing an example of the shortest path table. Specifically, FIG. 5 (a) is a diagram showing an example of a table of the shortest route table of the network 8 shown in FIG. 2 (a). FIG. 5 (b) is a diagram showing an example of a shortest path table of the network 8 shown in FIG. 2 (b). In the example of the table shown in FIG. 5, the numerical value of a certain column in a certain row indicates the number of hops of the path between the node indicated by the corresponding row and the node indicated by the corresponding column. For example, in the example of the table shown in FIG. 5A, the value “3” of the second column “base station 4b” of the first row “base station 4a” is the path “between the base station 4a and the base station 4b” The number of hops of the base station 4a-transfer device 7a-transfer device 7b-base station 4b "(the number of nodes passed before reaching the communication destination) is shown. The same applies to the other rows and columns. The shortest path table stored by the shortest path table storage unit 11 is determined by a node or the like in the network 8 including the session control device 1 when the terminal 3 connects to the network 8 when the topology changes or at any timing. , Updated by existing technology.

The session management table storage unit 12 stores a session management table which is established in the network 8 and manages a session between the terminal 3 and the destination 6. FIG. 6 is a diagram showing an example of a session management table. Specifically, FIG. 6 (a) is a diagram showing an example of a session management table of the network 8 shown in FIG. 2 (a). FIG. 6 (b) is a diagram showing an example of a session management table of the network 8 shown in FIG. 2 (b). In the example of the table shown in FIG. 6A, in the first record, for a session whose session name for identifying a session is “session 1”, a node in the network 8 that requires a route is the base station 4b, the relay function 2a, It shows that the gateway device 5 has a hop number of 6 (base station 4b-transfer device 7b-transfer device 7a-relay function 2a-transfer device 7a-transfer device 7b-gateway device 5). The other records are similar. The session management table stored by the session management table storage unit 12 is updated according to the existing technology by a node or the like in the network 8 including the session control device 1 when the topology changes or at any timing.

The activation detection unit 13 detects a node newly activated (created) in the network 8. Specifically, from the node newly activated in the network 8, the activation detection unit 13 selects a node name (for example, "relay function 2b") for identifying the node and a unit name indicating a unit to which the node belongs. (For example, "Relay function") is received. Next, the activation detection unit 13 updates the topology management table stored by the topology management table storage unit 10 based on the received node name and the like. For example, with respect to the table example of the topology management table shown in FIG. 4 (a), the table of the topology management table shown in FIG. 4 (b) is displayed by the start detection unit 13 as the relay function 2b is newly started. Updated to Note that the update of the topology management table is realized by the existing technology, and the information and the like necessary for the update are appropriately received from a newly activated node, a node connected to the node, and the like.

Next, the activation detection unit 13 updates the shortest path table stored by the shortest path table storage unit 11 based on the updated topology management table. For example, with respect to the example of the table of the shortest path table shown in FIG. 5 (a), the start detection unit 13 adds the relay function 2b to the topology. Updated to the example table. The update of the shortest route table is realized by the existing technology. For example, the activation detection unit 13 constructs an undirected graph between nodes from the information of the topology management table, and updates the shortest path table by calculating the shortest path using the Dijkstra method. When the update of the shortest route table is completed, the activation detection unit 13 outputs information indicating the completion, and the node name and unit name of the newly activated node to the path calculation unit 14.

The route calculation unit 14 receives the information indicating the completion from the start detection unit 13 and the node name and unit name of the newly started node, the shortest route table stored by the shortest route table storage unit 11, and Based on the session management table stored by the session management table storage unit 12, it is determined whether or not there is a session whose path is shortened among the currently established sessions (calculating a session whose path is shortened) . More specifically, when the route calculation unit 14 transfers relaying by the first relay function that is currently relaying a session to relay by a second relay function that is not currently relaying the session, It is determined whether the session path is shortened after migration compared to before migration. The route calculation unit 14 determines whether or not the route is shortened, triggered by the addition of the second relay function to the network (the input of the information indicating completion from the start detection unit 13). It is also good.

The details will be described below. The path calculation unit 14 collates the unit name of each node in the network 8 stored in advance in the session control device 1 with the unit name input from the activation detection unit 13, and receives the input from the activation detection unit 13. Extract the node with the same name as the unit name. For example, when the unit name of the newly activated relay function 2b is "relay function" and the unit name of the relay function 2a among the nodes in the network 8 is the same "relay function", the path calculation unit 14 The relay function 2b determines that the relay function 2a is to be shifted at the time of scale-out. Next, the path calculation unit 14 stores the shortest path of the session when the relay of the session is shifted to the relay by the relay function 2b instead of the relay by the relay function 2a, the shortest path stored by the shortest path table storage unit 11 Calculated using the existing technology such as Dijkstra method based on the table and the session management table stored by the session management table storage unit 12 and whether the number of hops of the session path becomes smaller after migration than before migration Determine For example, for the session of “session 1” shown in FIG. 6A, when the relay by relay function 2a is shifted to the relay by relay function 2b, the number of hops in the session path is shifted from “6” before the shift. It is determined that "4" (base station 4b-transfer device 7b-relay function 2b-transfer device 7b-gateway device 5) becomes smaller.

Next, when the route calculation unit 14 determines that the route becomes short (the number of hops of the route decreases), the session as the determination target included in the session management table stored by the session management table storage unit 12 is Update to the session determined to shorten the route. For example, as illustrated in FIG. 6B, the path calculation unit 14 performs “session 1” having the hop number “6” shown in FIG. The relay by the relay function 2a is updated with the information regarding the session transferred to the relay by the relay function 2b.

If the path calculation unit 14 determines that there is a shortened session (when the session management table is updated), information on the updated session (session name (for example, “session 1”) or the like) and relay in the session to be transferred Preparation for transition of information about the source relay function that is the relay function 2 (for example, relay function 2a) that is scheduled to stop and information about the destination relay function that is the relay function 2 (for example, relay function 2b) that is to be newly relayed It is output to the instruction unit 15, the state synchronization instruction unit 16, the transition instruction unit 17 and the session information deletion instruction unit 18. The transition preparation instructing unit 15, the state synchronization instructing unit 16, the transition instructing unit 17 and the session information deletion instructing unit 18 respectively shift the information on the updated session input from the route calculating unit 14, the information on the transfer source relay function, and the transfer. The updated session, the transfer source relay function, and the transfer destination relay function are identified (determined) using the information related to the first relay function. If the route calculation unit 14 determines that there are a plurality of shortened sessions, it prepares to move a set of [information on updated session, information on transfer source relay function, information on transfer destination relay function] for each session. It is output to the instruction unit 15 and the state synchronization instruction unit 16. Then, in the subsequent processing, processing is performed on each set. In the present embodiment, processing in the case where there is only one session to be shortened will be described, but the same applies to the case where there are a plurality of sessions. When the path calculation unit 14 determines that there is no shortened session (when the session management table is not updated), the process is not particularly performed.

When the information on the updated session, the information on the transfer source relay function, and the information on the transfer destination relay function are input from the path calculation unit 14, the transfer preparation instructing unit 15 receives the information on the input transfer destination relay function. A session transition preparation instruction is transmitted to the transition destination relay function (for example, the relay function 2b) indicated by. The session migration preparation instruction is a request for session migration newly issued by the session control device 1 along with the input information on the updated session, the input information on the migration source relay function, and the session migration preparation instruction this time. It contains a number (information to specify). The session transfer preparation instruction is an instruction (information indicating) to prepare for the transfer destination relay function to transfer from the transfer source relay function to the updated session.

The state synchronization instructing unit 16 receives the information on the updated session, the information on the transfer source relay function, and the information on the transfer destination relay function from the path calculation unit 14, and indicates the relay indicated by the information on the transfer source relay function. A state synchronization instruction is transmitted to the function 2 (for example, the relay function 2a). The state synchronization instruction is an instruction (information indicating) to transmit (synchronize) information on a session to be transferred (a session in which the transfer source relay function is relaying) to the relay function 2 indicated by the information on the transfer destination relay function. . Here, the information on the session to be transferred is specifically the information recorded in association with the session to be transferred in the transfer source relay function, for example, a transfer entry on the session or state information on the session Etc. The state synchronization instruction includes identification information (or address value) of the transfer destination relay function and information on the input transitioning session. Note that the address value of the transfer destination relay function may be derived by an indirect method, such as an arbitrary node included in the network 8 derives from the identification information of the transfer destination relay function (address values of other nodes are also included) As well).

Based on the transmission of the session transition preparation instruction by the transition preparation instruction unit 15 and the transmission of the state synchronization instruction by the state synchronization instruction unit 16, the information on the session to be transitioned from the transition source relay function to the transition destination relay function is replicated (synchronization) State synchronization is performed between the source relay function and the destination relay function. Note that data communication that has arrived at the transition source relay function after state synchronization has been performed may be set to be transferred to the transition destination relay function. When the state synchronization is completed, the transition destination relay function transmits a session transition preparation completion to the state synchronization instructing unit 16 of the session control device 1. The session transition preparation completion is information that indicates that the session transition preparation is completed. The session migration preparation completion includes the request number received by the migration destination relay function. Based on this request number, the session control device 1 can determine which request the session transition preparation for is completed.

When the transition instructing unit 17 receives the session transition preparation completion from the transition destination relay function, the relay by the transition source relay function of the session is relay destination relay function for the session to be migrated corresponding to the request number included in the session transition preparation completion. Sends a session transition instruction, which is an instruction to shift to relay according to the above, to the nodes included in the network 8. More specifically, the migration instruction unit 17 refers to the session management table stored by the session management table storage unit 12 and is a node included in the session to be migrated, which is not a scale-out target node (for example, FIG. In the session management table shown in 6 (b), a session transfer instruction is transmitted to the base station 4b and the gateway device). The session transfer instruction includes information on a session to be transferred (for example, "session 1") and information on a transfer destination relay function (for example, relay function 2b) (for example, identification information of relay function 2b or an address value of relay function 2b). And.

Based on the transmission of the session transition instruction to the node by the transition instruction unit 17, the node updates the transfer destination of the session. For example, each node transfers a session based on a session transfer destination table stored by each node. FIG. 7 is a diagram showing an example of a session transfer destination table. The table example shown in FIG. 7A shows the session transfer destination table stored by the node before transmission of the session transfer instruction, and the table example shown in FIG. 7B is updated after transmission of the session transfer instruction Shows the session transfer destination table. As shown in the example of the table shown in FIG. 7A, the transfer destination for "session 1" is "relay function 2a" before the transmission of the session transfer instruction, but "session 1" is used as information on the session to be transferred. After receiving the session transfer instruction including the information on the relay function 2b as the transfer destination relay function, the transfer destination is updated to "relay function 2b" for "session 1" as shown in the table example shown in FIG. 7 (b). It is done.

Each node, when updating the session transfer destination, adds a marker (a bit indicating marker information) indicating the last data communication to the header of the last packet transferred to the transfer destination of the session before updating. Give. The transition destination relay function that finally receives the packet to which the marker is assigned determines that all data communication in the session (old route) before transition has arrived by the reception. Then, when the transfer destination relay function determines that all have arrived, the transfer destination relay function transmits, to the session information deletion instructing unit 18 of the session control device 1, a session transfer completion indicating that the session transfer has been completed. The session transfer completion includes the request number acquired when the transfer destination relay function receives a session transfer preparation instruction. Based on this request number, the session control device 1 can determine which request the transition of the session has been completed.

When the session information deletion instruction unit 18 receives the session transition completion from the transition destination relay function, it transmits a session information deletion request instructing deletion of session information to the transition source relay function. Here, the session information is information stored in association with the session (for example, a transfer entry related to the session, or status information related to the session). The session information deletion request includes information on the updated session (eg, session name).

Based on the transmission of the session information deletion request to the transition destination relay function by the session information deletion instruction unit 18, the transition destination relay function transmits the session stringed to the session indicated by the information on the updated session included in the session information deletion request. Delete information

The above is the description of each functional block of the session control device 1.

Subsequently, session control processing by the session control system 9 including the session control device 1 will be described using the sequence diagram shown in FIG.

First, in the state before performing session control processing, the terminal 3 and the destination 6 perform data communication through a session of “terminal 3-base station 4b-relay function 2a-gateway device 5-destination 6” (Step S1). Next, the relay function 2b is newly activated (step S2). Next, the start detection unit 13 of the session control device 1 detects the relay function 2b that has been newly started, and the topology management table and the shortest path table are updated (step S3). Next, it is determined by the path calculation unit 14 of the session control device 1 whether or not there is a session in which the path is shortened (step S4). If it is determined in S4 that there is no session for shortening the route, this processing ends. If it is determined in S4 that there is a session in which the path is shortened (here, it is determined that the path is shortened when the session of S1 is shifted from relay by relay function 2a to relay by relay function 2b), The path management unit 14 of the session control device 1 updates the session management table.

Next, a session transition preparation instruction is transmitted to the relay function 2b by the transition preparation instruction unit 15 of the session control device 1 (step S5). Next, the state synchronization instruction unit 16 of the session control device 1 transmits a state synchronization instruction to the relay function 2a (step S6). Next, state synchronization is performed between the relay function 2a that has received the state synchronization instruction and the relay function 2b (step S7). When the state synchronization is completed, session transfer preparation completion is transmitted to the session control device 1 by the relay function 2b (step S8).

Next, a session transition instruction is transmitted by the transition instruction unit 17 of the session control device 1 to the base station 4b and the gateway device 5, which are nodes included in the session of S1 (step S9). Next, the session transfer destination table is updated in the base station 4b and the gateway 5 (step S10). Next, the packet to which the marker is attached by the old route is transferred (step S11), and the session transfer completion is transmitted to the session control device 1 by the relay function 2b that finally receives the packet (step S11). S12). Next, a session information deletion request is sent to the relay function 2a by the session information deletion instruction unit 18 of the session control device 1 (step S13). Next, session information is deleted in the relay function 2a (step S14). In the state after the session control process is performed by the above-described session control process, the terminal 3 and the destination 6 are through the session of “terminal 3-base station 4b-relay function 2b-gateway device 5-destination 6”. Data communication (step S15).

The block diagram used for the explanation of the above-mentioned embodiment has shown the block of a functional unit. These functional blocks (components) are realized by any combination of hardware and / or software. Moreover, the implementation means of each functional block is not particularly limited. That is, each functional block may be realized by one physically and / or logically coupled device, or directly and / or indirectly two or more physically and / or logically separated devices. It may be connected by (for example, wired and / or wireless) and realized by the plurality of devices.

For example, the session control device 1 or the like in one embodiment of the present invention may function as a computer that performs the session control process of the present invention. FIG. 9 is a diagram showing an example of a hardware configuration of the session control device 1 according to an embodiment of the present invention. The session control device 1 described above may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007 and the like.

In the following description, the term "device" can be read as a circuit, a device, a unit, or the like. The hardware configuration of the session control device 1 may be configured to include one or more of the devices illustrated in the figure, or may be configured without some devices.

Each function in the session control device 1 causes the processor 1001 to perform an operation by reading predetermined software (program) on hardware such as the processor 1001, the memory 1002, etc., communication by the communication device 1004, memory 1002 and storage This is realized by controlling reading and / or writing of data in 1003.

The processor 1001 operates, for example, an operating system to control the entire computer. The processor 1001 may be configured by a central processing unit (CPU: Central Processing Unit) including an interface with a peripheral device, a control device, an arithmetic device, a register, and the like. For example, the activation detection unit 13, the route calculation unit 14, the transition preparation instruction unit 15, the state synchronization instruction unit 16, the transition instruction unit 17, the session information deletion instruction unit 18 and the like described above may be realized by the processor 1001.

Also, the processor 1001 reads a program (program code), a software module or data from the storage 1003 and / or the communication device 1004 to the memory 1002, and executes various processing according to these. As a program, a program that causes a computer to execute at least a part of the operations described in the above embodiments is used. For example, the activation detection unit 13, the route calculation unit 14, the transition preparation instruction unit 15, the state synchronization instruction unit 16, the transition instruction unit 17 and the session information deletion instruction unit 18 are stored in the memory 1002 and control programs operated by the processor 1001. , And may be realized for other functional blocks as well. The various processes described above have been described to be executed by one processor 1001, but may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The program may be transmitted from the network via a telecommunication line.

The memory 1002 is a computer readable recording medium, and includes, for example, at least one of a ROM (Read Only Memory), an EPROM (Erasable Programmable ROM), an EEPROM (Electrically Erasable Programmable ROM), and a RAM (Random Access Memory). It may be done. The memory 1002 may be called a register, a cache, a main memory (main storage device) or the like. The memory 1002 can store a program (program code), a software module, and the like that can be executed to perform session control processing according to an embodiment of the present invention.

The storage 1003 is a computer readable recording medium, and for example, an optical disc such as a CD-ROM (Compact Disc ROM), a hard disc drive, a flexible disc, a magneto-optical disc (eg, a compact disc, a digital versatile disc, a Blu-ray A (registered trademark) disk, a smart card, a flash memory (for example, a card, a stick, a key drive), a floppy (registered trademark) disk, a magnetic strip, and the like may be used. The storage 1003 may be called an auxiliary storage device. The above-mentioned storage medium may be, for example, a database including the memory 1002 and / or the storage 1003, a server or any other suitable medium.

The communication device 1004 is hardware (transmission / reception device) for performing communication between computers via a wired and / or wireless network, and is also called, for example, a network device, a network controller, a network card, a communication module, or the like. For example, the activation detection unit 13, the transition preparation instruction unit 15, the state synchronization instruction unit 16, the transition instruction unit 17, the session information deletion instruction unit 18, and the like may be realized by the communication device 1004.

The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, and the like) that receives an input from the outside. The output device 1006 is an output device (for example, a display, a speaker, an LED lamp, etc.) that performs output to the outside. The input device 1005 and the output device 1006 may be integrated (for example, a touch panel).

In addition, devices such as the processor 1001 and the memory 1002 are connected by a bus 1007 for communicating information. The bus 1007 may be configured by a single bus or may be configured by different buses among the devices.

In addition, the session control device 1 includes hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), and a field programmable gate array (FPGA). And part or all of each functional block may be realized by the hardware. For example, processor 1001 may be implemented in at least one of these hardware.

Next, the operation and effect of the session control device 1 configured as in the present embodiment will be described.

According to the session control device 1 of the present embodiment, when it is determined that the relay by the relay function 2 a is shifted to the relay by the relay function 2 b and the session path becomes shorter after the transition than before the transition, the relay function 2 a An instruction to cause the relay function 2b to transmit information on the session being relayed is transmitted to the relay function 2a. Since the said information is transmitted to the relay function 2b by this, the relay function 2b can perform relay reliably after transfer. Further, an instruction to shift the relay by the relay function 2a of the session to the relay by the relay function 2b is transmitted to the node. Thereby, the session established between the nodes in the network 8 can be reliably shifted from relay by the relay function 2a to relay by the relay function 2b. That is, the session can be transferred more reliably.

Here, in the system according to the prior art, when the relay function is scaled out and the relay function has a state of being associated with the session, a new relay is made to a place where the route is shorter than seen from a certain terminal. Even if the function is activated, communication can not be performed via the new relay function until the terminal is retouched. Since the rear touch of the terminal does not occur frequently, communication occurs over a long time until the rear touch occurs, resulting in unnecessary communication. According to the session control device 1 of the present embodiment, when the relay function 2 b is added to the network 8, the path calculation unit 14 determines whether or not the path is shortened. The addition of the relay function 2b to the network 8 means that the relay function has been scaled out. As a result, it is possible to immediately shift the session to the relay function in which the route becomes short in response to the scale-out of the relay function.

The session control system 9 can be applied to a control system in a mobile communication network, in particular a network operating according to the 3GPP standard, or an equivalent or a derivative thereof.

As described above, in the system according to the prior art, there is a problem that in the scale-out with respect to the relay function having a state, even if a relay function having a shorter route is newly created from the viewpoint of a certain terminal, the relay function is not used until the rear touch was there. According to the session control device 1 of the present embodiment, the route is shortened by passing through the new relay function from among the sessions passing through the other relay functions, triggered by the participation of the new relay function started up by the scale out. The terminal can be calculated and a sequence can be run to transition the state from the original relay function to the new relay function.

As mentioned above, although this embodiment was described in detail, it is clear for persons skilled in the art that this embodiment is not limited to the embodiment described in this specification. This embodiment can be implemented as a modification and a change mode, without deviating from the meaning and range of the present invention which become settled by statement of a claim. Therefore, the description of the present specification is for the purpose of illustration and does not have any limitation on the present embodiment.

The notification of information is not limited to the aspects / embodiments described herein, and may be performed in other manners.

Each aspect / embodiment described in the present specification is LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G, 5G, FRA (Future Radio Access), W-CDMA (Registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, UWB (Ultra-Wide Band), The present invention may be applied to a system utilizing Bluetooth (registered trademark), other appropriate systems, and / or an advanced next-generation system based on these.

As long as there is no contradiction, the processing procedure, sequence, flow chart, etc. of each aspect / embodiment described in this specification may be reversed. For example, for the methods described herein, elements of the various steps are presented in an exemplary order and are not limited to the particular order presented.

The specific operation that is supposed to be performed by the base station in this specification may be performed by its upper node in some cases. In a network of one or more network nodes with a base station, the various operations performed for communication with the terminals may be the base station and / or other network nodes other than the base station (eg, It is clear that it may be performed by MME or S-GW etc but not limited to these). Although the case where one other network node other than a base station was illustrated above was illustrated, it may be a combination of a plurality of other network nodes (for example, MME and S-GW).

Information and the like may be output from the upper layer (or lower layer) to the lower layer (or upper layer). Input and output may be performed via a plurality of network nodes.

The input / output information or the like may be stored in a specific place (for example, a memory) or may be managed by a management table. Information to be input or output may be overwritten, updated or added. The output information etc. may be deleted. The input information or the like may be transmitted to another device.

The determination may be performed by a value (0 or 1) represented by one bit, may be performed by a boolean value (Boolean: true or false), or may be compared with a numerical value (for example, a predetermined value). Comparison with the value).

Each aspect / embodiment described in this specification may be used alone, may be used in combination, and may be switched and used along with execution. In addition, notification of predetermined information (for example, notification of "it is X") is not limited to what is explicitly performed, but is performed by implicit (for example, not notifying of the predetermined information) It is also good.

Although the present invention has been described above in detail, it is apparent to those skilled in the art that the present invention is not limited to the embodiments described herein. The present invention can be embodied as modifications and alterations without departing from the spirit and scope of the present invention defined by the description of the claims. Accordingly, the description in the present specification is for the purpose of illustration and does not have any limiting meaning on the present invention.

Software may be called software, firmware, middleware, microcode, hardware description language, or any other name, and may be instructions, instruction sets, codes, code segments, program codes, programs, subprograms, software modules. Should be interpreted broadly to mean applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, etc.

Also, software, instructions, etc. may be sent and received via a transmission medium. For example, software may use a wireline technology such as coaxial cable, fiber optic cable, twisted pair and digital subscriber line (DSL) and / or a website, server or other using wireless technology such as infrared, radio and microwave When transmitted from a remote source, these wired and / or wireless technologies are included within the definition of transmission medium.

The information, signals, etc. described herein may be represented using any of a variety of different techniques. For example, data, instructions, commands, information, signals, bits, symbols, chips etc that may be mentioned throughout the above description may be voltage, current, electromagnetic waves, magnetic fields or particles, optical fields or photons, or any of these May be represented by a combination of

The terms described in the present specification and / or the terms necessary for the understanding of the present specification may be replaced with terms having the same or similar meanings.

The terms "system" and "network" as used herein are used interchangeably.

In addition, the information, parameters, and the like described in the present specification may be represented by absolute values, may be represented by relative values from predetermined values, or may be represented by corresponding other information. .

The names used for the parameters described above are in no way limiting. In addition, the formulas etc. that use these parameters may differ from those explicitly disclosed herein.

A base station can accommodate one or more (e.g., three) cells (also called sectors). If the base station accommodates multiple cells, the entire coverage area of the base station can be divided into multiple smaller areas, each smaller area being a base station subsystem (eg, a small base station RRH for indoor use: Remote Communication service can also be provided by Radio Head. The terms "cell" or "sector" refer to a part or all of the coverage area of a base station and / or a base station subsystem serving communication services in this coverage. Furthermore, the terms "base station" "eNB", "cell" and "sector" may be used interchangeably herein. A base station may be called in terms of a fixed station (Node station), NodeB, eNodeB (eNB), access point (access point), femtocell, small cell, and the like.

The mobile station may be a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communication device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, by those skilled in the art. It may also be called a terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable term.

The terms "determining", "determining" as used herein may encompass a wide variety of operations. "Judgment", "decision" are, for example, judging, calculating, calculating, processing, processing, deriving, investigating, looking up (for example, a table) (Searching in a database or another data structure), ascertaining may be regarded as “decision”, “decision”, etc. Also, "determination" and "determination" are receiving (e.g. receiving information), transmitting (e.g. transmitting information), input (input), output (output), access (Accessing) (for example, accessing data in a memory) may be regarded as “judged” or “decided”. Also, "judgement" and "decision" are to be regarded as "judgement" and "decision" that they have resolved (resolving), selecting (selecting), choosing (choosing), establishing (establishing) May be included. That is, "judgment" "decision" may include considering that some action is "judged" "decision".

The terms "connected", "coupled" or any variants thereof mean any direct or indirect connection or coupling between two or more elements, It can include the presence of one or more intermediate elements between two elements that are “connected” or “coupled”. The coupling or connection between elements may be physical, logical or a combination thereof. As used herein, the two elements are by using one or more wires, cables and / or printed electrical connections, and radio frequency as some non-limiting and non-exclusive examples. It can be considered "connected" or "coupled" to one another by using electromagnetic energy such as electromagnetic energy having wavelengths in the region, microwave region and light (both visible and invisible) regions.

As used herein, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

Any reference to an element using the designation "first," "second," etc. as used herein does not generally limit the quantity or order of those elements. These designations may be used herein as a convenient way of distinguishing between two or more elements. Thus, reference to the first and second elements does not mean that only two elements can be taken there, or that in any way the first element must precede the second element.

As long as “including”, “comprising”, and variations thereof are used in the present specification or claims, these terms as well as the term “comprising” are inclusive. Intended to be Further, it is intended that the term "or" as used in the present specification or in the claims is not an exclusive OR.

Throughout the present disclosure, when articles are added by translation, such as a, an and the in English, for example, these articles are plural unless the context clearly indicates otherwise. Shall be included.

DESCRIPTION OF SYMBOLS 1 ... Session control apparatus, 2.2a * 2b ... Relay function, 3 ... Terminal, 4. 4a * 4b ... Base station, 5 ... Gateway apparatus, 6 ... Destination, 7 * 7a * 7b ... Transfer apparatus, 8 ... Network, 9 session control system 10 topology management table storage unit 11 shortest path table storage unit 12 session management table storage unit 13 activation detection unit 14 route calculation unit 15 transition preparation instruction unit 16 ... state synchronization instruction unit, 17 ... transition instruction unit, 18 ... session information deletion instruction unit.

Claims

A session control device for controlling a session, which is a logical communication path established between nodes in a network, comprising:
When the relay by the first relay function, which is the function of relaying the session, is shifted to the relay by the second relay function, which is the function of not relaying the session, the transition is made after the transition as compared to before the transition. If you decide that the session path will be shorter,
Transmitting an instruction to the first relay function to cause the second relay function to transmit information related to the session relayed by the first relay function;
Transmitting to the node an instruction to shift relay by the first relay function of the session to relay by the second relay function;
Session control device.
The session control device according to claim 1, wherein it is determined whether or not the path is shortened in response to the addition of the second relay function to the network.