Study On QoS Routing Algorithms, Load Balancing Routing Algorithms And Related Technology

QoS Routing is an important technology of QoS control system. To find a feasible path that has sufficient resource and can meet the requirements of QoS constraints is a basic task of QoS Routing. With the rapid growth of various traffics, especially the multimedia traffic, the congestion of internet becomes more and more serious. Load balancing is one of solutions that proposed to solve the congestion problem. Load balancing aims to optimize resource of network and improve the efficiency of utilization of resource. Load balancing routing algorithms make the traffic load of links, routers and switches in network smoother. It can avoid that a part of resource of network be overused while others not be used efficiently. With the development of technology of wireless networks, spectrums become more and more lack. Therefore, cognitive radio (CR), a wireless network with opportunity access, aroused interesting of many researchers. But it brings a different difficult problem to the routing algorithm research. This paper focus on QoS Route, load balancing route and relative technology.DCLC (Delay Constrainted Least Cost) problem is a famouse problem of QoS Route. A novel approach based on Lagrangian relaxation was proposed. In this approach, the cost parameter of links is absorbed into delay parameter and taked the delay parameter into account whiles each iteration process. This approach can find a feasible path during non-polynomial. Simluations and analysis proved the correctness of porposed algorithm.Ant Colony Algorithms are one of bionics algorithms and are used for solving the non-polynomial completed problems usually. According to the characteristic of network, a new ant colony algorithm was proposed. The new algorithm adopts parallel iteration mode while a new routing request arrival. Simulations show that the proposed algorithm with parallel iteration mode has the same performance with the algorithms adopted the serial iteration mode but spend less time.It is very important for MPLS networks to build a LSP (Label Switched Path) reasonably. Bandwidth is a key constrained parameter of LSP request usually. How to choose a reasonable path which can both satisfy the request of bandwidth and improve the utilization of resource of MPLS networks is a difficult problem. Based on the maximal flow algorithm, a novel algorithm, named MCRA, was proposed. While finding path, MCRA considers not only the influence of maximal-flow-zero-edge, but also the competition of bandwidth between every ingress-egress pairs. Simulations show that, comparing with other algorithms, MCRA can accept more LSP request for it can balancing the load more efficiently.Recently, more and more wireless networks begin to support multi-rate transmission. It makes the routing problem of wireless mesh network (WMN) more and more complex. In this paper, a novel routing algorithm for multi-rate wireless mesh network is presented. It aims to achieve load balance and support multi-rate effectively. Alternating prisoner's dilemma is a famous problem in game theory. Tit for tat (TFT) strategy is the best solution of this dilemma. Inspired with TFT, a new conception, named consanguinity, is been proposed by this new algorithm. This conception is used to inspirit nodes of network to cooperate with each other. The users with higher consanguinity will glad to forward RREQ packet. Simulation result shows that the proposed approach can improve the performance of WMN effectively.In CR mesh network, the secondary users (SUs) share the spectrum with primary users (PUs) by opportunity access mode. The SUs must quit the using spectrum as soon as PUs appear in this spectrum. It means that must transmit its data as soon as possible. So, in CR mesh network, routing algorithms should take the spectrum allocation problem into account. The spectrum allocation algorithms are one of important domain of routing algorithms research in CR mesh network. This paper proposed a new approach, which is based on graph-theory and aims at two objectives: one is the sum of the allocated channel bandwidth is maximum, and the other is the number of users can be active simultaneity is maximum. The simulations show that the presented algorithm can improve the performance of spectrum allocation of CR mesh network.