Terabit Router Pim-sm Protocol Study

As the most popular intra-domain multicast routing protocol presently, PIM-SM has strong ability of transferring data. It is the main multicast protocol which Terabit router must realizes and its forwarding performance will exert direct influence on whether Terabit router can sustain high quality multicast applications commendably or not. Popular PIM-SM protocol implementation schemes are often difficult to accord with the architecture characteristics of Terabit router and to arrive at the forwarding performance which increasing data flux of Internet needs and the real-time characteristic of multicast applications. This paper introduces a distributing implementation scheme of PIM-SM to satisfy the requirements of Terabit routers for the sake of realizing self knowledge rights and improving forwarding performance. The key idea of the scheme is that the control plane and data plane of PIM-SM are separately implemented. In order to forward data as fast as possible, the data plane of protocol is carried out in TCAM+FPGA manner, the control plane is realized by software and they are connected through high-speed inner network. After a practical testing, it indicates the scheme can guarantee the integrity of protocol and raise the forwarding performance exceedingly which amounts to 10G interface line speed forwarding .In short, it can meet the need of Terabit router and is an efficient PIM-SM implementation scheme. The contents contained are below:> In terms of the characteristic of separated control plane and data plane and the demands on the implementation manner of Terabit router, it introduces a distributing implementation scheme on PIM-SM and has an analysis of the key issues of the scheme: how to achieve high transmitting speed and how to assure the coherence between protocol planes.> It introduces a high forwarding speed scheme by TCAM+FPGA manner, and has a detailed analysis of the implementation way, forwarding table format, the check table and forwarding arithmetic of the scheme, the feasibility of achieving 10G line speed forwarding .It also advances an optimism realization check table idea.> It analyzes the problem of plane coherence and introduces a way to solve it through message mechanism on Terabit router flat. It also studies the issues of poor performance produced by handling large number of data-driven messages, and introduces a kind of rate limitation arithmetic which is analyzed later.> It introduces the detailed implementation strategies of the scheme on Terabit router and carries out the practical testing especially on protocol coherence and forwarding performance .The test results then proves the advantage of the rationality, and the high performance of the scheme ,It also analyzes the existing problems and advances the betterment opinion and future work area.