Implementation And Application Of TDMoIP Based Media Gateway

TDMoIP is a technology of transmitting TDM traffic over PSN transparently .With the fast development of PSN nowdays , the core network and the access network are both becoming PSN but the traditional TDM application will still be existing for a long time, this is why TDMoIP was invented .Although the name the technology is called"TDMoIP", it can be used with various PSN like UDP/IP, MPLS, L2TPV3 or Eth. The thesis will introduce the details of the encapsulation format for the four different PSN above.TDMoIP is invented by RAD Data Communication , but it has become an international standard of ITU-T, IETF and MPLS/FR forum .There are 3 standards under IETF PWE3 group: TDMoIP, CESoPSN and SAToP.TDMoIP is focusing on low speed TDM rate (E1/T1, E3/T3 and STM-1/OC-3) over PSN application which is suitable for SME application or carrier's access network , while CESoPSN is focusing on higher TDM rate (STM-4/OC-12 and STM-16/OC-48)over PSN application which is suitable for carrier's core network. These two main standards have some difference in their implementation , for example: 1 TDMoIP is utilizing the fulfill level of the jitter buffer to get the frequency differance of the local clock and the clock source and then achieve the clock recovery ; while CESoPSN is utilizing the RTP byte in the overhead with hardware intervention to achieve the clock recovery .2 TDMoIP's AAL1 and AAL2 adaptation of the TDM data into TDMoIP packet makes it easy to interwork with legacy network like ATM , while CESoPSN is not relevant to AAL1 and AAL2 at all .This thesis will deliver a depth comparison of these two technologies.With a 10 years history , the implementation of TDMoIP used to be software based and FPGA based and now it is chipset based . RAD RJ-021 can provide up to four E1 or four serial ports per chipset and also can be cascaded to achive multi-ports . The TDMoIP chipset makes it easy to integrate TDMoIP technology into other technology platform. GePON is a pure Eth data platform , but with TDMoIP it has become a multi-service platform for both data and voice ; in some PSN based multi-service application , there is a need to distribute the TDM clock to the remote multi-service node like IP-DSLAM , TDMoIP clock module ( SFP based) at remote site can join the multi-cast group and get the clock from the central clock source and this is a must to ensure the TDM service quality .In conclusion , based on fact of the fast development of PSN and the existence of TDM application , TDMoIP technology will be a milestone of the history of communicaiton network technology development .