JP4864128B2 - Communication system and communication program - Google Patents

Description

  The present invention relates to a technology corresponding to resumption of initialization of an edge router that accommodates subscribers in a next generation network.

  Next generation network (NGN) to guarantee communication quality on the network for various services such as terrestrial digital TV broadcast re-transmission, telephone, and VOD (video on demand). Therefore, it is possible to control the band by SIP (Session Initiation Protocol) session control. The NGN transfer network has an access network composed of optical fibers and transmission devices for distributing them to the user's home, and a core network composed of a large-capacity router. The core network and the access network are connected via an edge router (SSE: Subscriber Service Edge). A user network including user terminals and routers in a user's home is connected to an access network via a home gateway (HGW) and accommodated in the SSE via the access network.

  A session control server (SSC) that accommodates users includes a SIP session control function unit (CSCF: Call Session Control Function) that performs session control by SIP and a network bandwidth management function unit (RACS) that controls SSE. Resource and Admission Control Subsystem) and a Subscriber Information Management Function Unit (NASS: Network AttachmentStamp) that performs IP address assignment and authentication to the user terminal by DHCP (Dynamic Host Configuration Protocol). In NGN, these functions perform processing in cooperation with each request by an SIP session, thereby realizing NGN-specific functions such as management of communication quality (QoS: Quality of Service).

Miyasaka, 2 others, “Bandwidth management and control technology in NGN”, NTT Technical Journal, October 2008, Vol. 20, No. 10, p. 22-23

  The SSE performs routing based on routing information managed by associating a transmission destination address with a transfer destination interface. A user terminal or HGW that is temporarily connected to the Internet acquires an IP address from NASS by DHCP. The SSE adds routing information with reference to the contents of communication by DHCP between the NASS and the user terminal, and appropriately transfers signals addressed to the user terminal and the HGW.

  However, when initialization of the SSE is restarted or when the failure of the physical interface of the SSE is recovered, the routing information in the SSE is reset, so that it is necessary to reset the routing information. If the routing information is not set correctly, the signal to the user terminal or the like is not correctly transferred, and the user terminal cannot communicate.

  The present invention has been made in view of the above, and an object of the present invention is to immediately reset a terminal and update routing information when a router resumes initialization.

  A communication system according to a first aspect of the present invention is a communication system including a bandwidth management device that controls an edge router and a subscriber management device that distributes setting information including an IP address to a subscriber terminal. Comprises a monitoring means for monitoring a failure of the edge router, and a notification means for notifying the subscriber management apparatus when the monitoring means detects that the edge router has been initialized again. When receiving, the request means for requesting resetting of the setting information to the subscriber terminal accommodated in the edge router and the setting information update request from the subscriber terminal are received, and the setting information is sent to the subscriber terminal. Distribution means for distributing.

  In the communication system, the bandwidth management information notifying means also notifies link aggregation number information when the edge router uses link aggregation.

  A communication program according to the second aspect of the present invention causes a computer to function as each means constituting the communication system.

  According to the present invention, when the router is initialized again, it is possible to immediately reset the terminal and update the routing information.

It is a block diagram which shows the structure of the communication system and NGN in this Embodiment. It is a schematic diagram which shows the connection structure of the edge router of the said system. It is a sequence diagram which shows the flow of a process at the time of initialization restart of an edge router.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of a communication system and NGN in the present embodiment. The core network 100 is composed of a large-capacity router, and is connected to another network via an edge router. The access network 200 includes an optical fiber and a transmission device for distributing the optical fiber to the user's home, and connects the user network in the user's home including the user terminals 61 and 62 and the core network 100. The core network 100 and the access network 200 are connected via an edge router (SSE) 5. The access network 200 and the user network are connected via a home gateway (HGW) 6.

  FIG. 2 is a schematic diagram showing the connection configuration of the SSE 5. The SSE 5 is connected to the core network 100, and includes a plurality of physical interfaces 51A and 51B, and is connected to the HGWs 6A, 6B, and 6C disposed at the user's home via the access network 200. The HGWs 6A, 6B, and 6C in each user's home are connected to user terminals such as IP phones 61A and 61C that use IPv4 and video equipment (STB: Set Top Box) 61B and 62C that use IPv6.

The SSE 5 has a function of transferring an input signal to an appropriate transmission destination. As a transfer destination, for example, there is another router in the core network 100 or a user network connected to the access network 200. The SSE 5 holds an IP address distributed by DHCP to the user terminals 61 and 62 and the HGW 6 as routing information. DHCP is a protocol that automatically assigns necessary setting information such as an IP address to the user terminals 61 and 62 and the HGW 6 that are temporarily connected to the Internet. Routing information is information for transferring a signal addressed to a specific IP address to an appropriate destination. For example, the user terminals 61 and 62 that have received the IP address of 192.168.0.1 are connected to the network interface 1 of the SSE 5 and the IP address of 192.168.0.2 is received to the network interface 2. When the user terminals 61 and 62 are connected, the routing information is configured as shown in Table 1 below. In this case, a signal addressed to 192.168.0.1 is transferred to the network interface 1.

  This routing information is stored in the SSE 5, but is reset when the initialization is restarted when the operation of the SSE 5 is unstable, or when the initialization is restarted when the physical interface is recovered from a failure. Therefore, in the present invention, the initialization restart of the SSE 5 is monitored, and when the initialization restart of the SSE 5 is detected, the routing information is reconstructed by the SSE 5.

  As shown in FIG. 1, the SSE 5 is connected to the SSC 1 arranged on the core network 100 and is monitored and controlled by the SSC 1. The SSC 1 includes a NASS function 2, a CSCF function 3, and a RACS function 4, and performs SSE 5 control, session control, and IP address assignment and authentication by DHCP. Each function provided in the SSC 1 may be configured by a computer including an arithmetic processing device, a storage device, a memory, and the like, and the processing of each function may be executed by a program. This program is stored in a storage device included in the SSC 1 and can be recorded on a recording medium such as a magnetic disk, an optical disk, or a semiconductor memory, or provided through a network. In addition, the configuration in which the SSC 1 includes each function is an example, and each function of the NASS function 2, the CSCF function 3, and the RACS function 4 may be configured by separate servers arranged in the core network 100.

  The NASS function 2 performs IP address assignment and authentication for the user terminals 61 and 62. In addition, an SSE initialization restart handling unit 22 that detects the restart of initialization of the SSE 5 and an IP address distribution unit 21 that requests the user terminals 61 and 62 to reset the IP address are provided.

  The CSCF function 3 performs session control by SIP, and notifies the information necessary for the RACS function 4 to perform bandwidth management. For example, when a session is established by a SIP INVITE message, the requested bandwidth and transfer quality are determined from the media information described in the SIP SDP (Session Description Protocol), and the RACS function 4 is notified.

  The RACS function 4 performs QoS management such as reserving a bandwidth by controlling the SSE 5 and also monitors the failure of the SSE 5 using SNMP (Simple Network Management Protocol), and notifies the NASS function 2 when the initialization of the SSE 5 is detected again. .

  Next, the flow of processing for updating the routing information held by the SSE when the SSE is initialized again will be described.

  FIG. 3 is a sequence diagram showing the flow of processing when SSE initialization is resumed.

  The RACS function 4 performs failure monitoring of the SSE 5 by SNMP (step S11). SNMP is a protocol for monitoring and controlling communication devices connected to a network such as routers, computers, and terminals in a TCP / IP network.

  When the RACS function 4 detects the resumption of initialization of the SSE 5, it notifies the NASS function 2 to that effect (step S12). The RACS function 4 notifies the NASS function 2 of the SSE information that has been initialized again and the physical interface information that has been recovered from the failure. When the SSE 5 uses link aggregation, the link aggregation number information is notified. Link aggregation is a technology that virtually bundles a plurality of physical lines and treats them as if they were one line.

  The NASS function 2 that has received the notification of resuming initialization of SSE requests the user terminals 61 and 62 to reset the setting information including the IP address (step S13). Targets for which resetting is requested are user terminals 61 and 62 that are connected to the notified SSE and are affected by the loss of the routing information of SSE5. The user terminals 61 and 62 requesting resetting are notified from the RACS function 4 and information stored in the storage device provided in the NASS function 2, for example, information indicating which communication device is accommodated in which SSE 5. Determine based on. The request for resetting is performed by the NASS function 2 transmitting a DHCP reset (Reconfiguration) message.

  Receiving the reset request, the user terminals 61 and 62 request the NASS function 2 to update the setting information (step S14). The update request is made by the user terminals 61 and 62 transmitting a DHCP update (Renew) message.

  Receiving the update request from the user terminals 61 and 62, the NASS function 2 updates or redistributes address information to the user terminal (step S15). All communication between the NASS function 2 by DHCP and the user terminals 61 and 62 passes through the SSE 5, so that the SSE 5 detects the update of the IP address information by the DHCP and updates the routing information.

  Note that the HGW 6 performs the same processing as the user terminals 61 and 62 when the IP address is acquired from the NASS function 2 by DHCP.

  Therefore, according to the present embodiment, when the RACS function 4 monitors the failure of the SSE 5 that performs routing and detects the resumption of initialization of the SSE 5, the NASS function 2 is informed to the affected user terminals 61 and 62. A request is made to reset the setting information including the address, and the IP address or the like is updated or redistributed in response to the update request from each of the user terminals 61 and 62. Thereby, SSE5 can detect the update of IP address information by DHCP from communication with NASS function 2 and user terminals 61 and 62, and can update routing information.

1 ... SSC
2 ... NASS function 21 ... IP address distribution unit 22 ... SSE initialization restart support unit 3 ... CSCF function 4 ... RACS function 5 ... SSE
51A, 51B ... physical interface 6, 6A, 6B, 6C ... HGW
61, 62 ... User terminal 61A, 61C ... IP phone 61B, 62C ... STB
100 ... Core network 200 ... Access network

Claims (3)

In a communication system comprising a bandwidth management device that controls an edge router and a subscriber management device that distributes setting information including an IP address to a subscriber terminal,
The bandwidth management device includes:
Monitoring means for monitoring a failure of the edge router;
Notification means for notifying the subscriber management device when the monitoring means detects that the edge router is initialized again,
The subscriber management device is:
Request means for requesting resetting of the setting information to the subscriber terminal accommodated in the edge router when the notification is received;
A distribution means for receiving an update request for the setting information from the subscriber terminal and distributing the setting information to the subscriber terminal;
A communication system comprising:   2. The communication system according to claim 1, wherein said bandwidth management information notifying means also notifies link aggregation number information when said edge router uses link aggregation.   The communication program for functioning a computer as each means which comprises the communication system of Claim 1 or 2.

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