Study Of Network Convergence Based On Nortel ATM Switch

Asynchronous Transfer Mode (ATM) is widely applied in communications equipment of bank, finance, government and enterprises. ATM technology with less delay and good real-time performances can satisfy the requirement of multimedia communication by classifying one physical channel into several virtual circuits. It can support all kinds of users by assigning resources according to needs.The telecommunication's restructuring on May 2009, inevitably led to the two independent networks of original China Unicom and original China Netcom interconnect into unity manageable and interconnected whole network. Based on the features of original China Unicom and original China Netcom's ATM network, this thesis studies the key technology of network convergence in depth and proposes a new safe and steady scheme of network convergence. And the validation experiment based on the terminal of network management software is completed.The main works are as follows:1) ATM technology principle, signaling protocol and other related knowledge are introduced. Meanwhile, two kinds of ATM network routing protocols:the dynamic routing protocol PNNI and the static routing protocols IISP are discussed as the important aspects. Since the two routing protocols are not compatible, how to realize the two routing protocols interconnection is the one key issue to be solved in the network convergence.2) Based on the network switch of PASSPORT series of the original Unicom, this thesis performs a deep research on the basic circuit configurations including switch parameters and meaning of command. This thesis also introduces four basic circuit call configurations:the ATM SPVC, the combined SPVC-NPVC, the circuit of both ends frames relay and the frames relay calling ATM circuit.3) The different settings in routing protocols and node number of the original Netcom and original Unicom ATM networks are identified in the thesis. A new solution has been designed for network convergence by adding virtual component vf. The thesis connects two routing protocols and gives the implementation process on convergence in detail.The convergence scheme will not affect the stability of the network, and at the same time it can ensure the normal use of users. The above characteristics accord with the expectation of network operators on the network integrations.