CN101052021A - NGN network based on PSTN network structure - Google Patents

Abstract

The present invention relates to an NGN network based on PSTN network structure in the technical field of communication. A media gateway MG supporting IP over E1 interface is set in the time division multiplexing TDM network in the PSTN network. The MG accesses users downwards and exits upwards The IP over E1 interface is connected to the IP network through the TDM transmission network. The present invention uses the MG that supports the IP over E1 interface to replace the switch node or the remote switching module and the remote access module in the PSTN network. The PSTN network is transformed into a part of the NGN network. On the basis of reusing the existing network infrastructure and saving investment, users can be connected to the NGN network and enjoy various services of the NGN network.

Description

A NGN Network Based on PSTN Network Construction

technical field

The invention relates to the technical field of communication, in particular to an NGN network constructed based on a PSTN network.

Background technique

PSTN (Public Switched Telephone Network) network is a fixed telecommunications service network with a hierarchical structure, usually composed of switches of different levels, and remote switching modules, remote access modules, V5 access networks, WLL ( Wireless local loop), PBX (Public Exchange) and other network equipment. The switch and the network equipment are connected through a transmission network based on TDM (Time Division Multiplexing) technology, including direct connection based on E1, T1, SDH (Synchronous Digital Hierarchy), or SONET (Synchronous Optical Network) technology or formed by transmission equipment transmission network connection.

NGN network is based on IP technology, and it is a network separated from control and bearer. For existing PSTN users, including: POTS (traditional ordinary telephone service)/ISDN (Integrated Services Digital Network), PBX, V5 access network, WLL and other users, or users from other PSTN networks, MGC+MG is usually used access to the NGN (Next Generation Network) network. Among them, MGC (media gateway control) has the call control function of handling PSTN users; MG (media gateway) is used to convert the media service flow of PSTN users from the bearer format based on TDM technology to the bearer format based on IP, so as to communicate with the NGN network communicate with other users.

With the development and progress of technology, PSTN network will gradually evolve to NGN network. In the prior art, when transforming a PSTN network into an NGN network, an IP network is added by adding a router and/or a data transmission network, and a gateway is directly connected to the newly added IP network.

As can be seen from the above description, since IP networks are generally composed of routers and data transmission networks, adding an IP network generally means abandoning or modifying the existing TDM transmission network, resulting in loss of original investment by the operator, thereby increasing the cost of the operator.

Contents of the invention

The purpose of the present invention is to provide an NGN network constructed based on the PSTN network.

The purpose of the present invention is achieved through the following technical solutions:

A kind of NGN network based on PSTN network structure, comprises: the media gateway MG that supports IP over E1 interface is set in the time division multiplexing TDM network in PSTN network, described MG inserts user downwards, goes out IP over E1 interface upwards, Access the IP network through the TDM transmission network.

The border between the TDM network and the IP network is provided with a router supporting an IP over E1 interface for terminating the IP over E1 connection; or,

Set up an MG that supports IP over E1 interface and routing and forwarding functions to terminate IP over E1 connections.

One or more MGs supporting routing and forwarding functions are set between the MG and the IP network.

The MG uses a compressed media encoding format to transmit media streams.

The MG uses the compressed spare bandwidth as a redundant route to avoid failures of the TDM transmission network and forwarding nodes.

When the media data flow is transmitted on the TDM network, it adopts the form of IP packet and is carried on the TDM relay time slot for transmission.

When the media data stream is transmitted on the TDM network, it adopts the form of MPLS packets, so that the media stream is directly carried on the MPLS for transmission.

When the media data flow is transmitted on the TDM network, the media flow is carried on the MPLS in the form of IP packets.

When transmitting media streams on a TDM network, data packets are carried on digital circuits based on time-division multiplexing technology.

As can be seen from the technical solution provided by the present invention above, the present invention utilizes the MG that supports the IP over E1 interface to replace the switch node or the remote switching module and the remote access module in the PSTN network, thereby achieving a new IP network, On the basis of not changing the existing TDM transmission network, transform the PSTN network into a part of the NGN network. On the basis of reusing the existing network infrastructure and saving investment, users can be connected to the NGN network and enjoy various services of the NGN network.

Description of drawings

Fig. 1 is a schematic diagram of networking of an embodiment of the method of the present invention;

Fig. 2 is a schematic diagram of networking of multiple MGs set on the boundary between the MG and the TDM.

Detailed ways

The core idea of the present invention is to provide a NGN network based on the PSTN network structure, and use the MG supporting IP over E1 interface to replace the switch node or the remote switching module and the remote access module in the PSTN network. Network, on the basis of not changing the existing TDM transmission network, transform the PSTN network into an NGN network.

The present invention provides a kind of NGN network based on PSTN network structure, and the networking after the transformation of one embodiment is shown in Figure 1, in the existing TDM network of PSTN network, MG is set, and described MG supports IP over E1 interface , the MG connects downward to POTS/ISDN, PBX, V5 access network, WLL access network or other types of users, upwards through the IP over E1 interface, and accesses the IP network through the TDM transmission network. The call control of the IP network is implemented by the MGC.

On the boundary between TDM network and IP network, a router supporting IP over E1 interface can be set up to take out IP packets from TDM relay time slots and forward them to the IP network, thereby terminating the IP over E1 connection.

On the boundary between the TDM network and the IP network, the MG that supports IP over E1 and is connected to the IP network can also be used for forwarding. At this time, the MG needs to support the routing and forwarding function.

Between the routers or MGs supporting IP over E1 interfaces on the MG and TDM borders, multiple MGs can be set up for forwarding media streams, as shown in Figure 2, the intermediate MGs also need to support routing and forwarding functions.

When the media data flow is transmitted on the TDM network, it may be in the form of an IP packet, which is carried on the TDM relay time slot for transmission.

When transmitting media streams on the TDM network, in addition to using the bearer format of VoIP over E1, it can also be transmitted through the bearer format of VoMPLS over E1 or VoIP over MPLS over E1. For example, the form of MPLS package is used to directly carry the media stream on MPLS, that is, the form of VoMPLS. Or the media flow is carried on the MPLS in the form of IP packets, that is, the form of VoIPoMPLS. At this time, the MG that accesses the user, and the router or MG at the edge of the IP network need to support the function of the LER (Label Edge Router) device in MPLS; the intermediate MG needs to support the function of the LSR (Label Switching Router) device in the MPLS network.

When transmitting media streams on a TDM network, data packets in VoIP, VoMPLS, VoMPLSoIP and other bearer formats can also be carried on T1, SDH, SONET or other digital circuits based on time-division multiplexing technology.

Since the MG can compress the media data stream, the compression codec format can be used to compress the media data when transmitting the media stream. When the data flow is transmitted on the TDM network, the bandwidth occupation can be greatly reduced. For example, when using the G.729 compression encoding format, it can save 37Kbps bandwidth compared with the traditional switch. If the compression codec is supported, the occupied bandwidth can be further saved by about 52Kbps.

When the bandwidth occupation is greatly reduced, the spare bandwidth can be used for redundant routing, which can avoid failures of TDM transmission network and forwarding nodes and improve reliability. For example, the access MG can configure two or more routes at the same time to reach different NGN network border routers or MGs respectively. If there is a problem with the route being used due to the failure of the TDM transmission network or border router or MG, you can switch to another route to improve network reliability.

To sum up, the present invention utilizes the MG that supports IP over E1 interface to replace the switch node or the remote switching module and the remote access module in the PSTN network, and realizes the new IP network without changing the existing TDM transmission network. Transform the PSTN network into a part of the NGN network on the basis of the network. On the basis of reusing the existing network infrastructure and saving investment, users can be connected to the NGN network and enjoy various services of the NGN network.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed in the present invention can easily think of changes or Replacement should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (9)

1, a kind of NGN network based on PSTN network structure, it is characterized in that, comprising: the media gateway MG that supports IP over E1 interface is set in the time division multiplexing TDM network in PSTN network, described MG connects user downward, upward Out of the IP over E1 interface, through the TDM transmission network to access the IP network. 2. A kind of NGN network based on PSTN network structure as claimed in claim 1, it is characterized in that, the border of described TDM network and IP network is provided with the router that supports IP over E1 interface, is used for terminating IP over E1 connection; Or , Set up an MG that supports IP over E1 interface and routing and forwarding functions to terminate IP over E1 connections. 3. The NGN network based on PSTN network according to claim 1 or 2, characterized in that one or more MGs supporting routing and forwarding functions are set between the MG and the IP network. 4. The NGN network constructed based on the PSTN network according to claim 1, wherein the MG uses a compressed media coding format to transmit media streams. 5. The NGN network constructed based on the PSTN network according to claim 4, wherein the MG utilizes the compressed spare bandwidth as a redundant route to avoid failures of the TDM transmission network and forwarding nodes. 6. A kind of NGN network based on PSTN network structure as claimed in claim 1, 4 or 5, it is characterized in that, when the media data stream is transmitted on the TDM network, it adopts the form of IP packet and carries it in the TDM relay time slot upload. 7. A kind of NGN network based on PSTN network structure as claimed in claim 1, 4 or 5, it is characterized in that, when the media data stream is transmitted on the TDM network, it adopts the form of MPLS packet, so that the media stream is directly carried on the MPLS upload. 8. A PSTN-based NGN network according to claim 1, 4 or 5, wherein when the media data stream is transmitted on the TDM network, the media stream is carried on the MPLS in the form of IP packets. 9. A PSTN-based NGN network according to claim 1, 4 or 5, characterized in that when transmitting media streams on the TDM network, data packets are carried on digital circuits based on time-division multiplexing technology.

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