CN1878162A - Mapping method for protocol interconnection entity to superposition transmitting-receiving code signalling - Google Patents

本发明公开了一种协议互通实体对重叠收发码信令的映射方法，包括以下步骤：第一IWU接收到足够的号码足以判断路由时，向第二IWU或SIP服务器发送INVITE请求；第二IWU或SIP服务器向被叫PSTN侧发送IAM信息，IAM信息由第一IWU根据接收到的IAM和SAM生成；第一IWU收到后续的SAM时，向第二IWU或SIP服务器发送INFO请求，INFO请求的From tag、Call－ID、To与INVITE请求中的From tag、Call－ID、To相同，INVITE请求和INFO请求的Request－line字段中的被叫号码是第一IWU暂时收到的主叫PSTN侧发送的所有号码；第二IWU或SIP服务器向被叫PSTN侧发送SAM，并返回200响应给第一IWU。本发明中通过IWU进行了ISUP的OVERLAP信令和SIP/SIP－I信令之间的相互映射，保证了信令能够穿越多个IWU，实现方法简单，占用资源少。

The invention discloses a method for mapping overlapping transceiving code signaling by a protocol interworking entity, which includes the following steps: when the first IWU receives enough numbers to judge the route, it sends an INVITE request to the second IWU or a SIP server; the second IWU Or the SIP server sends IAM information to the called PSTN side, and the IAM information is generated by the first IWU according to the received IAM and SAM; when the first IWU receives the subsequent SAM, it sends an INFO request to the second IWU or SIP server, and the INFO request The From tag, Call-ID, and To are the same as the From tag, Call-ID, and To in the INVITE request. The called number in the Request-line field of the INVITE request and the INFO request is the calling PSTN temporarily received by the first IWU. All numbers sent by the PSTN side; the second IWU or SIP server sends a SAM to the called PSTN side, and returns a 200 response to the first IWU. In the present invention, mutual mapping between ISUP OVERLAP signaling and SIP/SIP-I signaling is carried out through the IWU, which ensures that the signaling can pass through multiple IWUs, and the implementation method is simple and occupies less resources.

一种协议互通实体对重叠收发码信令的映射方法A method for mapping protocol interworking entities to overlapping transceiving code signaling

技术领域technical field

本发明涉及通讯设备中的信令映射方法，特别是一种通过SIP(SessionInitiation Protocol，会话发起协议)中的消息机制来实现IWU(Interworking Unit，协议互通实体)对OVERLAP(重叠收发码)信令的映射方法。The present invention relates to the signaling mapping method in the communication equipment, especially a kind of through the message mechanism in the SIP (SessionInitiation Protocol, session initiates agreement) to realize IWU (Interworking Unit, protocol interworking entity) to OVERLAP (overlapped sending and receiving code) signaling The mapping method.

背景技术Background technique

RFC3261(Request for Comments：3261，2002年6月出版，第10.1节，第56～57页)中规定了SIP服务器之间的信令接口。ITU组织颁布的TRQ.2815和Q.1912.5规定了IWU之间携带ISUP(ISDN User Part，ISDN用户部分)信息的SIP信令接口(SIP-I)。当呼叫的主被叫的其中任一方为PSTN(PublicSwitched Telephone Network，公共交换电路网络)用户，且呼叫信令经过至少两个IWU时，要求IWU能够将ISUP信令映射成SIP/SIP-I信令，反之亦然。RFC3261 (Request for Comments: 3261, published in June 2002, section 10.1, pages 56-57) specifies the signaling interface between SIP servers. TRQ.2815 and Q.1912.5 promulgated by the ITU organization stipulate the SIP signaling interface (SIP-I) carrying ISUP (ISDN User Part, ISDN user part) information between IWUs. When either the caller or the called party is a PSTN (Public Switched Telephone Network, public switched circuit network) user, and the call signaling passes through at least two IWUs, the IWUs are required to be able to map the ISUP signaling into SIP/SIP-I signaling orders, and vice versa.

但当主叫用户为PSTN用户，且该用户端局对其实施OVERLAP收号方式；从PSTN网络发往IWU的IAM(Initial Address Message，初始地址消息)消息只携带了一部分被叫号码，后续的被叫号码将在SAM(Subsequent AddressMessage，后续地址消息)消息依次携带。目前在RFC3578(Request forComments：3578，2003年8月出版)和Q.1912.5中定义了ISUP的Overlap消息向SIP消息映射的机制，这种机制的缺点是实现起来比较复杂，占用过多的SIP消息的事务层资源。However, when the calling user is a PSTN user, and the user end office implements the OVERLAP number collection method for it; the IAM (Initial Address Message, initial address message) message sent from the PSTN network to the IWU only carries a part of the called number. The called number will be carried sequentially in the SAM (Subsequent Address Message) message. Currently, RFC3578 (Request for Comments: 3578, published in August 2003) and Q.1912.5 define the mechanism for mapping ISUP Overlap messages to SIP messages. The disadvantage of this mechanism is that it is more complicated to implement and takes up too many SIP messages. The transaction layer resource.

发明内容Contents of the invention

本发明的目的在于解决RFC3578和Q.1912.5中定义的ISUP的Overlap消息向SIP消息映射机制的实现复杂，占用资源过多的缺点，提供一种协议互通实体对重叠收发码信令的映射方法。The purpose of the present invention is to solve the shortcomings of the Overlap message of ISUP defined in RFC3578 and Q.1912.5 to the SIP message mapping mechanism, which is complicated and takes up too many resources, and provides a method for mapping the overlapping sending and receiving code signaling of protocol interworking entities.

为了实现上述目的，本发明提供了一种协议互通实体对重叠收发码信令的映射方法，用于在主叫方为PSTN用户时，实现多个IWU之间通过SIP消息来承载ISUP的OVERLAP信息，其中，包括以下步骤：In order to achieve the above object, the present invention provides a mapping method of protocol interworking entities to overlapping transceiving code signaling, which is used to realize the OVERLAP information of ISUP carried by SIP messages between multiple IWUs when the calling party is a PSTN user , which includes the following steps:

步骤1，第一IWU接收到足够的号码足以判断路由时，向第二IWU或SIP服务器发送INVITE请求，所述INVITE请求的Request-line字段中的被叫号码是所述第一IWU暂时收到的主叫PSTN侧发送的所有号码；Step 1, when the first IWU receives enough numbers to judge the route, it sends an INVITE request to the second IWU or SIP server, and the called number in the Request-line field of the INVITE request is temporarily received by the first IWU All numbers sent by the PSTN side of the calling party;

步骤2，所述第二IWU或SIP服务器向被叫PSTN侧发送IAM信息，所述IAM信息由所述第一IWU根据接收到的IAM和SAM生成；Step 2, the second IWU or SIP server sends IAM information to the called PSTN side, and the IAM information is generated by the first IWU according to the received IAM and SAM;

步骤3，第一IWU收到后续的SAM时，向第二IWU或SIP服务器发送INFO请求，所述INFO请求的From tag、Call-ID、To与所述INVITE请求中的From tag、Call-ID、To相同，所述INFO请求的Request-line字段中的被叫号码是所述第一IWU暂时收到的主叫PSTN侧发送的所有号码；Step 3, when the first IWU receives the subsequent SAM, it sends an INFO request to the second IWU or SIP server, the From tag, Call-ID, To of the INFO request and the From tag, Call-ID in the INVITE request , To are the same, the called number in the Request-line field of the INFO request is all the numbers sent by the calling PSTN side temporarily received by the first IWU;

步骤4，所述第二IWU或SIP服务器向被叫PSTN侧发送SAM，并返回200响应给所述第一IWU。Step 4, the second IWU or the SIP server sends a SAM to the called PSTN side, and returns a 200 response to the first IWU.

上述的协议互通实体对重叠收发码信令的映射方法，其中，所述步骤1中，所述第一IWU没有接收到足够的号码来判断路由时，设置一第一定时器来等待接收后续的SAM。In the above-mentioned mapping method of the protocol interworking entity to the overlapping sending and receiving code signaling, in the step 1, when the first IWU does not receive enough numbers to judge the route, a first timer is set to wait for receiving subsequent SAM.

上述的协议互通实体对重叠收发码信令的映射方法，其中，所述步骤3中，第二IWU或SIP服务器在等待后续号码时，设置一第二定时器，所述第二定时器超时，第二IWU回484响应，并释放呼叫。The above-mentioned method for mapping the protocol interworking entity to the overlapping sending and receiving code signaling, wherein, in the step 3, the second IWU or the SIP server sets a second timer when waiting for the subsequent number, and the second timer expires, The second IWU responds back with 484 and releases the call.

上述的协议互通实体对重叠收发码信令的映射方法，其中，所述步骤3与步骤4之间还包括步骤：The above-mentioned method for mapping protocol interworking entities to overlapping code signaling, wherein, steps between step 3 and step 4 include:

第二IWU或SIP服务器根据INFO请求中的From tag和Call-ID，找到对应的呼叫实例，并判断INFO请求的Request-URI中的号码是否比已经收到的所有号码的长度长，如果不是，返回200响应给所述第一IWU；如果是，则进一步判断已经收到的所有号码是否是INFO请求的Request-URI中的号码一个子集，如果不是，返回200响应给所述第一IWU；如果是，从ISUP封装中取出SAM，并进入所述步骤4。The second IWU or SIP server finds the corresponding call instance according to the From tag and Call-ID in the INFO request, and judges whether the number in the Request-URI of the INFO request is longer than the length of all the numbers already received, if not, Returning a 200 response to the first IWU; if yes, further judging whether all the numbers received are a subset of the numbers in the Request-URI of the INFO request, if not, returning a 200 response to the first IWU; If yes, remove the SAM from the ISUP package and proceed to step 4 as described.

上述的协议互通实体对重叠收发码信令的映射方法，其中，还包括步骤：The above-mentioned mapping method of the protocol interworking entity to the signaling of overlapping sending and receiving codes further includes the steps of:

所述第二IWU或SIP服务器接收被叫PSTN侧用户发送的ACM，并通过所述第一IWU发送到主叫方PSTN侧；The second IWU or SIP server receives the ACM sent by the called PSTN side user, and sends it to the calling party PSTN side through the first IWU;

所述第二IWU或SIP服务器接收被叫PSTN侧用户发送的ANM，并通过所述第一IWU发送到主叫方PSTN侧。The second IWU or the SIP server receives the ANM sent by the called PSTN side user, and sends it to the calling party PSTN side through the first IWU.

本发明中，通过IWU进行了ISUP的OVERLAP信令和SIP/SIP-I信令之间的相互映射，保证了OVERLAP信令能够穿越多个IWU，实现方法简单，占用资源少。In the present invention, mutual mapping between ISUP OVERLAP signaling and SIP/SIP-I signaling is carried out through the IWU, which ensures that the OVERLAP signaling can pass through multiple IWUs, and the implementation method is simple and occupies less resources.

下面结合附图和详细实施例对本发明进行详细说明。The present invention will be described in detail below in conjunction with the accompanying drawings and detailed embodiments.

附图说明Description of drawings

图1为本发明主被叫都为PSTN用户，采用OVERLAP收号方式的呼叫消息流程图。Fig. 1 is a call message flow chart of the present invention in which both the calling party and the called party are PSTN users and the OVERLAP number collection method is adopted.

具体实施方式Detailed ways

本发明提供了一种运用SIP协议的消息机制来实现IWU对ISUP的OVERLAP信令消息进行的方法。The invention provides a method for implementing the OVERLAP signaling message of the ISUP by the IWU using the message mechanism of the SIP protocol.

当IWU收到来自主叫方PSTN 1的IAM消息时，如果已有号码还不足以决定路由，则设置定时器，等待后续的SAM；当IWU接收到足够的号码足以判断路由时，向相邻的IWU或SIP服务器发送INVITE请求，其Request-line(请求行)字段中的被叫号码是当前IWU(即IWU1)所收到PSTN1侧的所有号码；When the IWU receives the IAM message from the calling party PSTN 1, if the existing number is not enough to determine the route, then set the timer and wait for the subsequent SAM; The IWU or SIP server of the user sends an INVITE request, and the called number in the Request-line (request line) field is all the numbers on the PSTN1 side received by the current IWU (ie IWU1);

当IWU1收到后续的SAM时，向相邻的IWU/SIP服务器IWU2发送INFO请求，该INFO的From(包括tag)、Call-ID、To与INVITE中的相同，ISUP封装中的内容为SAM，其Request-line字段中的被叫号码是当前IWU所收到PSTN侧的所有号码；When IWU1 receives the subsequent SAM, it sends an INFO request to the adjacent IWU/SIP server IWU2. The From (including tag), Call-ID, and To of the INFO are the same as those in the INVITE, and the content in the ISUP package is SAM. The called number in the Request-line field is all the numbers on the PSTN side received by the current IWU;

IWU/SIP服务器IWU2收到来自相邻IWU1的INVITE消息，如认为号码不全，设置定时器，等待后续的号码；当收到后续INFO请求(与之前的INVITE消息具有相同的Call-ID和From Tag)时，根据Request-line中的被叫号码信息，结合已接收的被叫用户号码，分析出后续号码信息，重置定时器；当收到足够的号码时，即可进一步路由；如定时器超时，IWU应回484响应，并释放呼叫；The IWU/SIP server IWU2 receives the INVITE message from the adjacent IWU1. If it thinks that the number is incomplete, set a timer and wait for the subsequent number; when it receives the subsequent INFO request (with the same Call-ID and From Tag as the previous INVITE message) ), according to the called number information in the Request-line, combined with the received called user number, analyze the follow-up number information, and reset the timer; when enough numbers are received, further routing can be performed; such as timer Timeout, IWU should respond with 484 and release the call;

IWU1如果向PSTN网络发送了IAM消息之后又收到封装了SAM消息的INFO请求，则将对SAM消息作相关处理之后，将其发往PSTN网络，并进行最后的处理。If IWU1 receives the INFO request encapsulated with the SAM message after sending the IAM message to the PSTN network, it will send the SAM message to the PSTN network after relevant processing, and perform final processing.

主被叫都为PSTN用户，采用OVERLAP收号方式的呼叫消息流程图如图1，本发明的运用SIP协议的消息机制来实现IWU对ISUP的OVERLAP信令消息进行映射的方法具体包括以下步骤：Both the calling party and the called party are PSTN subscribers, and the call message flow chart of the OVERLAP number receiving method is as shown in Figure 1. The method of using the message mechanism of the SIP protocol of the present invention to realize that the IWU maps the OVERLAP signaling message of the ISUP specifically includes the following steps:

步骤111，IWU1收到IAM消息，当现有号码不足以决定路由时设置定时器，并进入步骤112，如果现有号码足以决定路由则直接进入步骤113；Step 111, IWU1 receives the IAM message, sets a timer when the existing number is not enough to determine the route, and enters step 112, if the existing number is sufficient to determine the route, then directly enters step 113;

步骤112，IWU1收到后续SAM消息，直到已有号码足以决定路由；Step 112, IWU1 receives subsequent SAM messages until the existing number is enough to determine routing;

步骤113，IWU1向IWU2发送INVITE消息，其中可携带SDP信息(描述了IWU1下控制的媒体网关的媒体能力)，同时必须封装IAM信息，该IAM信息由IWU1根据接收到的IAM和多个SAM信息，采用特定的本地策略生成，具体生成方法参见《中国电信SIP顺从规范》；Step 113, IWU1 sends an INVITE message to IWU2, which can carry SDP information (describing the media capability of the media gateway controlled by IWU1), and must encapsulate IAM information at the same time, and the IAM information is used by IWU1 according to the received IAM and multiple SAM information , which is generated using a specific local policy. For the specific generation method, refer to "China Telecom SIP Compliance Specification";

步骤114，IWU2根据已有号码决定路由，并向PSTN2发送IAM请求；Step 114, IWU2 determines the route according to the existing number, and sends an IAM request to PSTN2;

步骤115，PSTN1向IWU1发送SAM消息，其中SAM消息携带了被叫的后续号码；Step 115, PSTN1 sends a SAM message to IWU1, wherein the SAM message carries the called follow-up number;

步骤116，IWU1收到后续的SAM时，发出INFO，该INFO的From tag和Call-ID与To第一个INVITE中的相同，ISUP封装中的内容为SAM；Step 116, when IWU1 receives the follow-up SAM, it sends INFO, the From tag and Call-ID of the INFO are the same as those in the first INVITE of To, and the content in the ISUP package is SAM;

步骤117，IWU2收到INFO时，根据From tag和Call-ID，找到对应的呼叫实例；判断INFO的Request-URI中的号码是否比已经收到的所有号码的长度长，如果不是，则说明该INFO到达IWU2过迟，进入步骤118；如果是，则进一步判断已经收到的所有号码是否是INFO的Request-URI中的号码一个子集，如果不是，说明该INFO有问题，进入步骤118；如果是，从ISUP封装中取出SAM；采用特定的本地策略处理后发往PSTN2，参见《中国电信SIP顺从规范》；在等待后续号码时，如定时器超时，IWU应回484响应，并释放呼叫；Step 117, when IWU2 receives the INFO, find the corresponding call instance according to the From tag and Call-ID; judge whether the number in the Request-URI of the INFO is longer than the length of all the numbers already received, if not, then explain the INFO arrives IWU2 too late, enters step 118; If yes, then further judge whether all numbers that have received are a subset of numbers in the Request-URI of INFO, if not, explain that this INFO has a problem, enter step 118; If Yes, take out the SAM from the ISUP package; process it with a specific local policy and send it to PSTN2, see "China Telecom SIP Compliance Specification"; when waiting for the follow-up number, if the timer expires, the IWU should respond with 484 and release the call;

步骤118，IWU2同时向IWU1回200响应；Step 118, IWU2 returns a 200 response to IWU1 at the same time;

步骤119到步骤122：对后续的SAM重复步骤115到步骤118的处理，直到所有后续的SAM处理完毕；Step 119 to step 122: repeat the processing from step 115 to step 118 for subsequent SAMs until all subsequent SAMs are processed;

步123，IWU2收到来自PSTN2的ACM(Address Complete Message，地址全消息)；Step 123, IWU2 receives the ACM (Address Complete Message) from PSTN2;

步骤124，IWU2将ACM消息封装在180消息中，发往IWU1；Step 124, IWU2 encapsulates the ACM message in a 180 message and sends it to IWU1;

步骤125，IWU1从180消息中获取ACM信息，处理之后发往PSTN1；Step 125, IWU1 obtains the ACM information from the 180 message, and sends it to PSTN1 after processing;

步骤126，IWU2收到来自PSTN2的ANM(Answer Message，应答消息)；Step 126, IWU2 receives ANM (Answer Message, response message) from PSTN2;

步骤127，IWU2将ANM消息封装在200消息中，发往IWU1；Step 127, IWU2 encapsulates the ANM message in a 200 message and sends it to IWU1;

步骤128，IWU1从200消息中获取ANM信息，处理之后发往PSTN1；Step 128, IWU1 obtains ANM information from the 200 message, and sends it to PSTN1 after processing;

至此，呼叫建立。So far, the call is established.

本发明中，通过IWU进行了ISUP的OVERLAP信令和SIP/SIP-I信令之间的相互映射，保证了OVERLAP信令能够穿越多个IWU。In the present invention, mutual mapping between ISUP OVERLAP signaling and SIP/SIP-I signaling is carried out through the IWU, which ensures that the OVERLAP signaling can pass through multiple IWUs.

采用本方法可以保证主叫为PSTN用户，采用OVERLAP方式收号的呼叫，在通过多个IWU时，能成功进行。Adopting this method can ensure that the calling party is a PSTN user, and the call that adopts the OVERLAP mode to receive the number can be successfully carried out when passing through multiple IWUs.

当然，本发明还可有其它多种实施例，在不背离本发明精神及其实质的情况下，熟悉本领域的技术人员当可根据本发明作出各种相应的改变和变形，但这些相应的改变和变形都应属于本发明所附的权利要求的保护范围。Certainly, the present invention also can have other multiple embodiments, without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention, but these corresponding Changes and deformations should belong to the scope of protection of the appended claims of the present invention.