Gmpls-based Ip The Over Wdm Intelligent Optical Network Survivability

At present, with the continuous development of optical communication technology, data services shows a "blowout" growth, and the number of WDM channels is increasing. Single-channel transmission rate also continuously rises from 2.5Gbit/s to 40Gbit/s. Optical transport networks becomes the first choice for transport networks because of its high-speed and broadband characteristics. As the use of DWDM and single wave velocity continuously increase, once a network failure causes failure of transmission services and results in huge losses. Thus, the survivability of networks has become critical measure to modern network design.In this thesis, taking IP/GMPLS over WDM for the example, the multi-layer network survivability mechanisms is studied, and mainly focus on the multi-layer integrated control technology based on control plain. Main works are as follows:(1) Through the research of network survivability, single network survivability strategy and the multi-layer network survivability strategy, a cross-layer coordination strategy is proposed by using the integrated control plane technology of IETF of GMPLS-based and improving GMPLS RSVP-TE protocol. The principle of'first be discovered, first be dealt with'be implemented by matching the priority with the node falure. The efficiency and flexibility of multi-layer network survivability are greatly improved by introducing management state, insulating the low-level fault and making quick change when fault occurred.(2) The congestion control is studied. Considering the low network survivability because of that the continouse increasing best efforts delivering flow does not use congestion control mechanism and leads to network congestion or even paralysis, a new control mechanism is proposed. A new control mechanism is presented by using WRR weighted repetition algorithm, which can give the queue to different weights according to its priority and distribute corresponding bandwidth so as to provide QoS guarantees.(3) The NS-2 simulation network is set up to simulate the cross-layer strategy, and verify the superiority of the strategy. The validity of this control mechanism is verified by simulating a TCP flow and non-competitive feedback UDP flow in a bottleneck link.