The Research On Multicast And Survivability In OTN

The 21st century is an information-oriented society. Massive transmission of information needs high-capacity communications network. This gives the transmission technology great challenges. OTN is the next-generation optical transport system, which combines advantages of SDH and WDM. It combines advantages of the optical domain and electrical domain processing and is an excellent technology of broadband large particle services transmission. As various broadband applications keep surging, there rises an urgent requirement on data communication networks to efficiently delivering multicast traffic. At the same time, the success of the Internet makes the network ubiquitous, which requires the network provide uninterrupted high-capacity and stable service. That is survivability. OTN, as the next-generation mainstream transport network technology, faces a more complex network environment. Survivability assurance is essential.This paper, based on the National High Technology Research and Development Program of China "OTN optical switching technology and equipment system with large-capacity"(No.2008AA01A328), focuses on the survivability assurance technology and multicast support technology, does a research on the algorithms of setting OTN multicast tree, proposes a more efficient way to protect the OTN multicast service, meantime designs and realizes some functions of supporting platform for embedded devices based on OTN network elements. The main contents of this paper are as following:1) About OTN multicast technology, describes multicast services transporting in Optical Transport Network, compares and studies OTN multicast routing algorithms and proposes a multicast routing algorithm suitable for new OTN grid network topology.2) About OTN survival technology, introduces new survivability technology--Pre-configured Cycle(P-Cycle), applies P-Cycle technology on OTN grid network protection and proposes a more efficient way to protect the OTN multicast service, that is P_Cycle-based Tree Protection Sharing Work and Reservation Capacity. Utilization of network resources increases nearly twice by using the method.3) Designs and realizes some functions of supporting platform for embedded devices based on OTN network elements. That is hot fix function, log recording saving function, power--on SDRAM checking function, upgrade of SD card drive and transplanting upgrade of embedded platform OS.