【正文】 gnalling MAP protocol layer, specific include: the SCCP, MTP3, MTP2, MTP1. The following will detail the role of the four layers as well as on the platform of CPCI which module processing: 1). MTP1 signaling data link layer: the physical layer corresponds to the OSI model. Functions of signaling data link is the first of its kind in the MTP level, define the physical, electrical, and functional properties of signaling data link. And signaling data link can be divided into digital signaling data link and simulate signaling data link. Rules used in digital signaling data link the rate of 64 KB/s (PCM group of a time slot transmission rate). In the simulation of signaling data link, such as using frequency division multiplexing transmission system of the signaling data link, stipulated by the rate of Kb/s. In our mobile munication work, and USES the digital signaling data link. MTP1 to MTP2 layer simple said it only provides a physical channel, the signaling messages are not to do any processing. Introduce China39。 There are two kinds of TDM speed, a 64 k (E1 line in a certain time slot), another is 2 m (using E1 line 31 slots)。 Their are quite different in the bearing layer, but the different is transparent to the upper user. TDM and ATM we called narrowband transmission and IP we called broadband transmission。s NO. 7 signalling work is three layer architecture, adopts double plane structure. Three layer structure are: senior signalling HSTP (distributed in all major provinces), lowlevel signalling LSTP (distribution in the prefecture level), signaling point SP (also known as end bureau, general distribution in the regional county)。 And collimating the way refers to the connection between the two signaling point is through one or more signalling transfer. Because signalling is transparent to users, as directly connected, so we call it a collimating even. Now the connection in the majority with collimation even the way in the . Introduce China39。 2) signalling (STP), was one of the signalling work entity, but it is neither a signal source point isn39。 If they are receiving signaling messages, you can call the signaling point for the purpose of signaling point。 Next we39。 Speech path channel to add their own monitoring function, because in road signalling link is same in signaling system does not represent the speech path is interlinked. The above focuses on the NO. 7 signalling classification and their respective characteristics. basic concept of NO. 7 signalling: 1 signaling links (Link) : namely physical channel is used to transmit signal, usually a time slot for the E1 line。 Easy to develop some upper application based on signaling. But there are advantages as well as to the way signaling proposes some special requirements: the safety of the channel transmission is higher。 High channel utilization。s number one signaling is signaling along with the road, and NO. 7 signaling is mon way signaling. Total signal based on its own structure and trigger out some advantages: signaling transmission speed。 According to the transmission channel points can be divided into a total signaling and road signaling. 2. To introduce total signaling and road signaling: along with the road signaling refers to transmit signaling link with speech path is a link。 According to the feature points can be divided into management signaling, line signal。 NO. 7 signalling system research In this paper The No. 7 signalling work is an important part of modern munication work, it supports the entire munication work business at present. Our country adopts No. 7 signalling work is business supporting work has a variety of functions, and has built a set of relatively perfect work system. Papers from No. 7 signalling work structure was introduced in detail our country currently in No. 7 signalling work maintenance and management work, is the No. 7 signalling work pipe system and the difference between the No. 7 signalling monitoring system, this paper introduces the SPC exchange in the No. 7 signalling system hardware and software configuration and maintenance, and the deficiency existing in the current work and the problems faced by the brief explanation. At the same time also sums up the NO. 7 signalling system in the future development direction. The introduction Strong monality of No. 7 signalling System (Signaling System No. 7) is the international telegraph and telephone consultative mittee (CCITT) in 1980, now No. 7 signalling through extended modified many times, has formed a plete System of Signaling. In the heart of the modern munication work users voice, data and control data transfer of control data (signaling) sent separately special transmitting signaling work is called the signalling work, No. 7 signaling work system is the signalling work system. No. 7 signaling work system is the core of the modern munication work, it supports the current all the business of the whole munication work, the telemunication work data work to the cellular telephone work the whole munication industry are dependent on the No. 7 signaling work system. No. 7 signaling work system itself is a data work, and provides a set of protocols and message types of standard, so all signaling and control information can be in the form of data message transmission and can support the infinite variety of data. No. 7 signalling work is one of the three supporting work of telemunication work, is an important part of telemunication work, its application is very extensive. So far our country has been established by senior signalling (HSTP), lowlevel signalling (LSTP) and a large number of signaling point (SP), consisting of tertiary really makes as neural work and supporting work of telemunication work. Therefore no. 7 signalling work operation quality directly af