Given a set of lightpath connection requests in an all-10 Gb/s optical dense wavelength division multiplexed (DWDM) Ethernet network, lightpaths are designed. In addition the wavelength channels are assigned subject t...Given a set of lightpath connection requests in an all-10 Gb/s optical dense wavelength division multiplexed (DWDM) Ethernet network, lightpaths are designed. In addition the wavelength channels are assigned subject to minimization of the channel blocking and provisional requests satisfying the limits due to accumulative linear dispersion effects over the hops. This paper proposes a routing and wavelength assignment scheme for DWDM long-haul optical networks that includes routing, assignment and reservation of different wavelength channels operating under the Generalized Multiprotocol Label Switching (GMPLS) environment. The GMPLS framework can offer an approach to implement IP over DWDM with variable weighting assignments of routes based on the limitations due to residual dispersion accumulated on the lightwave path. The modeling is implemented under the framework of an object-oriented modeling platform OMNeT++. Network performance tests are evaluated based mainly on a long-haul terrestrial fiber mesh network composed of as well as three topologies structured as chain, ring, and mesh configurations. Blocking probability of lightpath connection requests are examined with the average link utilization in the network employing variable number of wavelength channels in association with the limits of route distance due to linear chromatic and polarization mode dispersion effects.展开更多
In last decade,due to that the popularity of the internet, data-central traffic kept growing,some emerging networking requirements have been posed on the todays telecommunication networks,especially in the area of n...In last decade,due to that the popularity of the internet, data-central traffic kept growing,some emerging networking requirements have been posed on the todays telecommunication networks,especially in the area of network survivability.Obviously,as a key networking problem,network reliability will be more and more important.The integration of different technologies such as ATM,SDH,and WDM in multilayer transport networks raises many questions regarding the coordination of the individual network layers.This problem is referred as multilayer network survivability.The integrated multilayer network survivability is investingated as well as the representation of an interworking strategy between different single layer survivability schemes in IP via generalized multi-protocol label switching over optical network.展开更多
GMPLS(generalized multi protocol label switching)网络中的多约束QoS路由问题是要在诸如带宽、代价和延迟的约束条件下找到一条优化的路径.这个问题通常被认为是一个NP-完全问题.在研究共享风险链路组具有的启发信息的基础上,提出了...GMPLS(generalized multi protocol label switching)网络中的多约束QoS路由问题是要在诸如带宽、代价和延迟的约束条件下找到一条优化的路径.这个问题通常被认为是一个NP-完全问题.在研究共享风险链路组具有的启发信息的基础上,提出了一种具有共享风险链路启发信息的多约束预计算算法.该算法包含预计算和搜索两个部分.预计算主要是能创建和更新每个节点上的路由表.而后,搜索部分则可以在层次化的结构中选择满足约束条件的优化的路径.大量仿真数据表明,相应的方法能够取得满意的结果,可以有效地解决GMPLS网络中多约束的QoS路由问题.展开更多
文摘Given a set of lightpath connection requests in an all-10 Gb/s optical dense wavelength division multiplexed (DWDM) Ethernet network, lightpaths are designed. In addition the wavelength channels are assigned subject to minimization of the channel blocking and provisional requests satisfying the limits due to accumulative linear dispersion effects over the hops. This paper proposes a routing and wavelength assignment scheme for DWDM long-haul optical networks that includes routing, assignment and reservation of different wavelength channels operating under the Generalized Multiprotocol Label Switching (GMPLS) environment. The GMPLS framework can offer an approach to implement IP over DWDM with variable weighting assignments of routes based on the limitations due to residual dispersion accumulated on the lightwave path. The modeling is implemented under the framework of an object-oriented modeling platform OMNeT++. Network performance tests are evaluated based mainly on a long-haul terrestrial fiber mesh network composed of as well as three topologies structured as chain, ring, and mesh configurations. Blocking probability of lightpath connection requests are examined with the average link utilization in the network employing variable number of wavelength channels in association with the limits of route distance due to linear chromatic and polarization mode dispersion effects.
文摘In last decade,due to that the popularity of the internet, data-central traffic kept growing,some emerging networking requirements have been posed on the todays telecommunication networks,especially in the area of network survivability.Obviously,as a key networking problem,network reliability will be more and more important.The integration of different technologies such as ATM,SDH,and WDM in multilayer transport networks raises many questions regarding the coordination of the individual network layers.This problem is referred as multilayer network survivability.The integrated multilayer network survivability is investingated as well as the representation of an interworking strategy between different single layer survivability schemes in IP via generalized multi-protocol label switching over optical network.
文摘GMPLS(generalized multi protocol label switching)网络中的多约束QoS路由问题是要在诸如带宽、代价和延迟的约束条件下找到一条优化的路径.这个问题通常被认为是一个NP-完全问题.在研究共享风险链路组具有的启发信息的基础上,提出了一种具有共享风险链路启发信息的多约束预计算算法.该算法包含预计算和搜索两个部分.预计算主要是能创建和更新每个节点上的路由表.而后,搜索部分则可以在层次化的结构中选择满足约束条件的优化的路径.大量仿真数据表明,相应的方法能够取得满意的结果,可以有效地解决GMPLS网络中多约束的QoS路由问题.
