CN1738267A - Method for realizing media stream bypass - Google Patents

Abstract

The invention relates to a method for realizing media flow bypass. The method first obtains the location information of the calling user terminal and the called user terminal from the message; judges whether the calling user terminal and the called user terminal belong to the same preset user group according to the location information, if the calling user terminal If the terminal and the called user terminal belong to the same user group, then the media stream address of the agent user remains unchanged, otherwise, the media stream address of the agent user is replaced with the address of the agent; finally, call processing is continued. Because in this method, for users who meet the media stream bypass conditions, the media stream address information carried in the signaling message is no longer changed, so that the user's media streams are directly intercommunicated between terminals, and media stream bypassing is realized. Therefore, the occupation of network bandwidth resources by media streams is reduced, and the dependence on the forwarding performance of proxy devices is reduced.

Description

Methods for implementing media stream bypass

technical field

The invention relates to a multimedia communication technology, in particular to a method for realizing the media flow bypass function in the multimedia communication based on the Internet protocol.

Background technique

Softswitch and packet switching technology has become one of the most concerned hotspots in the industry because of its broad application prospects and the ability to meet people's diverse and personalized business needs.

Proxy (PROXY) is one of the important technologies in the network (especially represented by Next Generation Network (NGN)) with the above-mentioned technologies as the core. A general PROXY is composed of a signaling proxy and a media proxy. The working principles of the signaling proxy and the media proxy are shown in FIG. 1 .

Signaling Proxy (SP, Signaling Proxy):

For the terminal, the PROXY can be regarded as a softswitch system, that is, the registration and call messages of the terminal will be sent to the PROXY first, and the PROXY will be forwarded to the core softswitch system after signaling processing. On the other hand, the PROXY can be regarded as a terminal to the core softswitch system. The softswitch system first sends the call request to the PROXY, and the PROXY forwards it to the real called user terminal after signaling processing. Generally, the PROXY needs to support one or more of the protocols such as SIP, H.323, MGCP, and H.248. Since the PROXY participates in the entire call process, the PROXY can obtain the corresponding user registration, call and other detailed information.

Media Proxy (MP, Media Proxy):

PROXY Proxy for media streaming. All the media streams that the users represented by the PROXY communicate with the outside world are processed and forwarded by the PROXY. When the user under PROXY serves as the calling user terminal, the called address seen by the PROXY comes from PROXY; when the user under PROXY serves as the called user terminal, the called address seen by the calling user terminal is the address of PROXY.

FIG. 1 depicts a schematic diagram of a proxy process for signaling streams and media streams. The signaling flow of the terminal is finally processed by the server through the agent, and the media flow is also transferred through the agent. In the environment shown in Figure 1, the number of signaling packets is generally small, usually about 10 signaling packets for a call, and 30 to 50 packets per second for a media stream. Transiting media streams through the PROXY has some advantages. For example, the PROXY can mark the media stream with a QoS level identifier or provide functions such as legal interception. At the same time, there are also some problems in the transfer of media streams through PROXY:

1) High performance requirements for PROXY equipment: Since PROXY needs to process 30-50 media stream messages per second, in the case of a large number of users, PROXY must have high performance to be able to perform media streams forwarding.

2) Media streams occupy large network bandwidth resources: Media streams are all transferred through PROXY, which seriously occupies the network bandwidth of the communication network. Especially in the case of video applications, the network will have to use higher bandwidth resources for the transmission of media streams.

Therefore, there is a need to realize media stream bypass in the current multimedia communication based on the Internet protocol, that is, the media stream needs to be directly transmitted between terminals without being proxied through a PROXY, as shown in FIG. 2 .

Contents of the invention

The technical problem to be solved by the present invention is to provide a method for bypassing media streams. This method enables the media streams of users preset in the same user group to directly communicate between terminals, which can meet the requirements for realizing media streams in multimedia communications. Bypass needs.

In order to solve the above problems, the present invention provides a method for realizing media stream bypass, the method specifically includes: obtaining the location information of the calling user terminal and the called user terminal from the message; Whether the calling user terminal and the called user terminal belong to the same preset user group, if the calling user terminal and the called user terminal belong to the same user group, the media stream address of the agent user remains unchanged, otherwise the agent end The user's media stream address is replaced with the proxy's address; finally call processing continues.

The location information described in this method is user identity information or IP address, and in the process of obtaining the location information of the calling user terminal and the called user terminal, firstly, the user's identity should be taken as the user's location information, when When the identity identifier cannot be obtained, obtain the user's IP address as the user's location information. When the location information is the user's IP address, in order to further obtain the user's identity information, it can be judged whether the calling user terminal and the called user terminal belong to the same agent, and if so, according to the obtained user IP address The address is reversely searched for the call information of the calling user terminal, and the identity information of the calling user terminal is obtained from the call information.

In the process of judging whether the calling user terminal and the called user terminal belong to the same preset user group, you can first select the user on the agent side, determine the user group to which the user belongs according to the location information of the user, and then judge whether the other user Belongs to the user group to which the agent user belongs.

In order to realize the method of the present invention, a user group table needs to be established, and the user group table should include the user identification field that needs to bypass the media flow, and the IP address field corresponding to the user identification field. The user group table defines user groups used to implement media stream bypass, and the user groups are composed of users with direct intercommunication capabilities at the IP layer.

Compared with the prior art, the beneficial effects brought by the present invention are: in the method provided by the present invention, for users who meet the media stream bypass conditions, the media stream address information carried in the signaling message is no longer changed, In this way, the media streams of users in the same user group can be directly intercommunicated between terminals, so that the media streams belonging to the same user group that originally need to be processed through the proxy can no longer be transmitted through the IP network and processed by the proxy, thus reducing It reduces the occupation of network bandwidth resources by media streams, reduces the load on the network, and at the same time reduces the dependence on the forwarding performance of proxy equipment, so that the packet forwarding performance of the proxy is no longer one of the main factors that limit multimedia communication when the business volume increases.

Description of drawings

Fig. 1 is a schematic diagram of the network structure of the agent in the next generation network NGN;

Fig. 2 is the schematic diagram that realizes media flow bypass in the next generation network NGN;

Fig. 3 is an example diagram of a network structure that cannot realize media flow bypass;

Fig. 4 is the flow chart that realizes media flow bypass when agent end user is as calling party;

Fig. 5 is a flow chart of implementing media stream bypass when the agent user is called.

Detailed ways

The present invention provides a method for realizing media stream bypass, which is suitable for realization on proxy (PROXY) equipment, but is not limited to dedicated proxy equipment, and can also be implemented on other equipment with PROXY function .

In the VoIP system, terminals negotiate the addresses of media streams through signaling protocols. In the case of PROXY participation, PROXY changes the media stream address of the terminal to the address of PROXY, so one of the keys to realize media stream bypass is to directly transfer The original media stream address information is sent to the communication peer. However, not all networking structures can achieve media stream bypass. Figure 3 shows a situation where media stream bypass cannot be achieved. Terminal 1 and Terminal 2 are under different network address translation (NAT) devices. Moreover, NAT does not support Application Layer Gateway (ALG, Application Layer Gateway). If the addresses of the two terminals are directly informed to each other, the two terminals will not be able to communicate. In addition to the situation shown in Figure 3, there are other situations where media stream bypass cannot be implemented, such as different user terminals belonging to the same firewall. Therefore, the bypass function of the media stream can only be implemented when it is confirmed that the terminals can directly communicate with each other.

Due to the complex allocation of IP addresses and overlapping of IP addresses, the PROXY device cannot judge whether terminals can directly communicate with each other based on IP addresses, so additional information is required to participate in the judgment. The present invention adopts the mode of cooperative use of user identity (ID) information and user IP address to judge whether the media stream bypass can be implemented specifically.

The realization of the media flow bypass can be divided into the realization of the media flow bypass in the calling process and the realization of the media flow bypass in the called process because the calling party where the agent is located is different.

First, in order to implement the method for realizing media stream bypass provided by the present invention, user groups need to be defined in advance, that is, users who need to use media stream bypass and can perform media stream bypass are defined as a media stream bypass user group , and the user group is composed of users with direct intercommunication capabilities at the IP layer. Factors that affect the ability of users to communicate directly include: different user terminals belong to the same firewall; user terminals belong to different NATs, and NAT does not support the application layer gateway ALG, etc. Only different users defined in the same user group can The mutual bypass of the media flow is realized.

Usually, the user group is defined by the operator according to the needs of the users. Different sets of users can form different user groups for media stream bypass, and users in different LANs can form different user groups for media stream bypass. . For example, all users of company A form media stream bypass user group A, and all users of company B form media stream bypass user group B. Users of company A can realize mutual media stream bypass, and all users of company B Mutual media stream bypass can be realized, but since company A users and company B users belong to different user groups, media stream bypass cannot be realized between company A users and company B users.

According to the needs of the method for realizing media stream bypass, a better way of defining user groups is provided: a user group table is established in the PROXY system, and each unit in this user group table should include the following structure:

User terminal ID domain, which defines the range of user IDs that need to bypass media streams;

User terminal IP address field, which defines the IP address range.

For example: User ID group defines a range of phone numbers of a company (such as ****0001～****0999), and users of a domain name (such as *@company.com) belong to a user group, then these users The media streams between users can be bypassed, thus ensuring that these users can directly communicate with each other in the network.

The IP address field defines the set range of IP addresses corresponding to the above user IDs, that is, the IP address range of the terminal. This information is used when the agent user is on the called side and cannot obtain the caller ID information. IP address of the calling user terminal.

As mentioned above, one of the ways to implement the user group table can be: group id User terminal ID field User terminal IP address field

The calling process refers to a call initiated by a user on the agent side. It has been introduced in the background technology that all the media streams communicated between the users proxied by PROXY and the outside world are processed and forwarded by PROXY; When the user under the PROXY serves as the called user terminal, the called address seen by the calling user terminal is the address of the PROXY, as shown in the network structure shown in FIG. 1 . In the calling process, it is the user under the agent who actually initiates the call, but it can also be simply regarded as the call initiated by the agent.

Fig. 4 describes a preferred embodiment of a method for realizing media stream bypass when the proxy user is the calling user. Step 11 is that PROXY receives the call request of the calling user terminal; proceed to step 12, take out the called user terminal identity (ID) information in the call request, and take out the ID information of the calling user terminal simultaneously. In order to realize the establishment of the call, the ID information of the called user terminal will be carried in the call request sent to the agent, and the ID information of the calling user terminal may be directly carried in the message of the call request, or may not be carried. If it is not carried, it is necessary to extract the calling user terminal ID information from the corresponding registered user information recorded by the PROXY. Step 13 is to query in the user group table predefined in the system according to the acquired ID information of the calling user terminal and the ID information of the called user terminal, to determine whether the calling user terminal and the called user terminal belong to the same User group for media stream bypass. Since what is obtained is the ID information of the user terminal, when specifically judging whether it belongs to the same user group, the user group to which it belongs can first be determined by any end user, if the end user does not belong to any user group at this time, then It can be explained that the calling user and the called user do not belong to the same user group, otherwise continue to judge whether the user at the other end is also in the user group. If the calling user and the called user belong to the same media stream bypass user group defined by the system, proceed to step 14, and the media stream address of the calling user terminal is not changed, that is, the proxy address is no longer used to replace the calling user terminal media stream address, and continue call processing 16; if the calling user terminal and the called user terminal do not belong to the same media stream bypass user group, then proceed to step 15 to replace the subsequent media stream address of the calling user terminal is the address of PROXY, and call processing 16 is performed.

In the calling process, the IP address of the calling user terminal can also be obtained. At this time, the above judgment method can be applied to judge whether the calling user and the called user belong to the same user group, or the ID of the called user terminal can be used first. Identify and determine the user group to which it belongs, and then judge whether the calling user terminal also belongs to the user group. That is, when using the IP address of the calling user terminal, it is also possible to judge whether the media stream bypass can be realized. Since this judgment method increases the amount of judgment calculation, it is not recommended. When the ID information of the user terminal can be obtained, the call flow should be processed based on the ID information of the user terminal first.

In the actual call process based on the VoIP protocol, the process in which the agent user acts as the caller may include the interaction of multiple messages, that is, after judging whether they belong to the same user group of the media stream bypass, it does not The address must be replaced or reserved immediately, but this information is recorded, and this information will be used in the subsequent actual media stream address information exchange message to decide whether to replace or reserve the address.

The called process refers to the call when the user on the agent side is called. As described in the background art, when the user under the PROXY serves as the called user terminal, the called address seen by the calling user terminal is the address of the PROXY. Therefore, in the called process, the user under the agent acts as the called user terminal, but usually it can be simply regarded as the agent acting as the called terminal.

Fig. 5 describes a preferred embodiment of implementing the media stream bypass method when the agent user is the called party. Step 201 is that the PROXY receives an incoming call request; proceed to step 202 to take out the called user terminal identity (ID) information in the call request; further obtain the calling user terminal ID information.

The called process is different from the calling process, because the called agent may not be able to obtain the ID information of the calling user terminal. If the server does not deliver the calling user terminal information, the calling user terminal cannot be obtained ID information, this situation will occur when the calling terminal has not activated the caller display service; and in the calling process, the corresponding calling user terminal ID and called user terminal ID information can be obtained. At this point, step 203 should be performed to determine whether the ID information of the calling user terminal can be obtained.

If the ID information of the calling user terminal can be obtained, step 204 is performed to determine whether the calling user terminal and the called user terminal belong to the same user group, and if they belong to the same user group, then step 209 is performed to keep the media of the called user terminal. The stream address is unchanged, that is, the media stream address of the called user terminal is no longer replaced with the proxy address, and step 211 is performed to continue the call process, otherwise the media stream address of the called user terminal is replaced with the proxy address, and step 211 is performed to continue the call deal with. In this case, since the ID information obtained is all user terminals, any end user can determine the user group to which it belongs when making a specific judgment. If the end user does not belong to any user group at this time, then it can be explained that the calling user and The called user does not belong to the same user group, otherwise continue to judge whether the other end user is also in the user group.

If it is judged that the ID information of the calling user terminal cannot be obtained, then step 205 should be performed to obtain the IP address information of the calling user terminal from the incoming call request, and then step 206 is performed after obtaining the IP address information of the calling user terminal, according to the received The ID information of the calling user terminal is searched in the user group table of the media stream bypass, to determine the user group to which the called user belongs, if the called user terminal does not belong to any user group, then proceed to step 210, and the called user terminal The media stream address of the terminal is replaced with the address of the proxy, and step 211 is performed to continue the call processing; if the called user terminal belongs to a certain user group, then step 207 is performed to obtain the IP address corresponding to the user group from the user group table domain information, and proceed to step 208 to determine whether the obtained IP address of the calling user terminal belongs to the obtained IP address domain corresponding to the user group where the called user terminal is located, if the IP address of the calling user terminal is in the In the IP address domain, it shows that the calling user terminal and the called user terminal belong to the same user group, then proceed to step 209, keep the media stream address of the called user terminal unchanged, and perform the call processing in step 211, if the calling user terminal If the IP address of the terminal is not in the IP address field corresponding to the user group where the called user terminal is located, it means that the calling user terminal and the called user terminal do not belong to the same user group. At this time, the bypass of the media stream cannot be realized, and the steps should be performed. 210. Replace the media stream address of the called user terminal with the proxy address, and perform call processing in step 211.

Since the ID information of the calling user terminal may not be obtained in the called process, but only the IP address can be obtained, at this time, it can be judged whether the calling user and the called user belong to the same agent, when the calling user terminal and the called user When the terminals belong to the same PROXY, the PROXY can record information such as the IP address of the calling user terminal, and the called user terminal can reversely find the call information of the calling user terminal based on the IP address of the calling user terminal, thereby obtaining the caller's ID information of the user terminal. At this time, whether the calling user terminal and the called user terminal belong to the same user group can be judged based on the ID information of the calling user, instead of judging based on the IP address of the calling user terminal.

There are corresponding alternative methods for processing the above-mentioned called process, which can also achieve the same purpose. For example, after only obtaining the ID information of the called user terminal and the IP address of the calling user terminal, it is also possible to first search in the user group table of the media stream bypass according to the IP address of the calling user terminal. The address does not belong to the IP address field corresponding to any user group in the user group table, then the address of the called user terminal is replaced with the address of the agent, and the call is processed; if the IP address of the calling user terminal belongs to the user group table IP address field corresponding to a certain user group in the user group, then obtain the user ID field corresponding to the user group, and judge whether the called user terminal belongs to the user group to which the calling user terminal belongs according to the ID information of the called user terminal. If the calling user terminal and the calling user terminal belong to the same user group, keep the address of the called user terminal unchanged and perform call processing. If the called user terminal and the calling user terminal do not belong to the same user group, the called user terminal The terminal's address is replaced with the agent's address, and call processing proceeds. This method is not recommended because it will increase the amount of computation for judging whether the calling user terminal and the called user terminal belong to the same user group during the specific implementation process.

In the called process, the IP address of the called user terminal can be obtained. At this time, the above judgment method can be applied to judge whether the calling user and the called user belong to the same user group according to the IP address of the called user terminal. First, the user group to which the calling user terminal belongs is determined by the ID or IP address of the calling user terminal, and then it is judged whether the called user also belongs to the user group. That is, when using the IP address of the called user, it is also possible to judge whether the media stream bypass can be realized, but this method is not recommended. When the ID information of the user terminal can be obtained, the call flow should be processed based on the ID information of the user terminal first.

In the actual call process based on the VoIP protocol, the process in which the agent user acts as the caller may include the interaction of multiple messages, that is, after judging whether they belong to the same user group of the media stream bypass, it does not The address must be replaced or reserved immediately, but this information is recorded, and this information will be used in the subsequent actual media stream address information exchange message to decide whether to replace or reserve the address.

In a call flow, there may be multiple agents between the calling user and the called user. In this case, the method provided by the present invention can also realize the bypass of the media flow. That is, when the message passes through each agent, the location information of the user terminal in the message is obtained, and then it is judged whether the calling user and the called user belong to the same user group according to the location information of each user terminal that can be obtained, and according to the judgment The result determines whether to replace the media stream address information carried by the user terminal in the signaling message, and finally continues the call processing.

The method for implementing media stream bypass provided by the present invention has been introduced in detail above. In this paper, specific examples are used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only used to help understand the method of the present invention. and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation and scope of application. limits.

Claims (7)

1, a kind of method that realizes Media Stream Bypass is characterized in that:

1) from message, obtains the positional information of call subscriber terminal and called user terminal;

2) judge according to described positional information whether call subscriber terminal and called user terminal belong to the same user's group that presets, if call subscriber terminal and called user terminal belong to same user's group, the Media Stream address of then keeping the agent side user terminal remains unchanged, otherwise the Media Stream address of agent side user terminal is replaced with agency's address;

3) carry out call treatment.

2, the method for realization Media Stream Bypass as claimed in claim 1 is characterized in that: described positional information is User Identity information or IP address information.

3, the method for realization Media Stream Bypass as claimed in claim 1, it is characterized in that, the described process of obtaining the positional information of call subscriber terminal and called user terminal of step 1) is: the identify label of at first obtaining the user is as user position information, in the time that described identify label can't be obtained, obtain user's IP address as user position information.

4, the method for realization Media Stream Bypass as claimed in claim 3, it is characterized in that also comprising: when positional information is user's IP address, judge whether call subscriber terminal and called user terminal belong to same agency, if, then according to the call information of the IP address reverse find call subscriber terminal that obtains, and from this call information, obtain the identification information of this call subscriber terminal.

5, as the method for claim 1 or 3 described realization Media Stream Bypass, it is characterized in that step 2) the described process of judging whether call subscriber terminal and called user terminal belong to the same user group that presets is specially:

21) user of selection one agent side determines that according to this user position information the user under this user organizes;

22) judge whether another user belongs to the affiliated user's group of this agent side user.

6, as the method for claim 1 or 5 described realization Media Stream Bypass, it is characterized in that: described user's group realizes the user's of Media Stream Bypass set for needs, and this set is made up of the user who has direct intercommunication ability at the IP layer.

7, the method for realization Media Stream Bypass as claimed in claim 1, it is characterized in that: before step 1), also comprise the step that generates user's group table, comprise the User Identity territory that need carry out Media Stream Bypass in described user's group table, and the pairing IP address field in this User Identity territory.

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