Wang Wendong

Autonomic QoS Management Mechanism in Software Defined Network

With the increase of network complexity, the flexibility of network control and management becomes a nontrivial problem. Both Software Defined Network (SDN) and Autonomic Network technologies are sophisticated technologies for the network control and management. These two technologies could be combined together to construct a software defined self-managing solution for the future network. An autonomic QoS management mechanism in Software Defined Network (AQSDN) is proposed in this paper. In AQSDN, the various QoS features can be configured autonomically in an OpenFlow switch through extending the OpenFlow and OF-Config protocols. Based on AQSDN, a novel packet context-aware QoS model (PCaQoS) is also introduced for improving the network QoS. PCaQoS takes packet context into account when packet is marked and managed into forwarding queues. The implementation of a video applications prototype which evaluates the self-configuration feature of the AQSDN and the enhancement ability of the PCaQoS is presented in order to validate this design.

Autonomicity design in OpenFlow based Software Defined Networking

Software Defined Networking (SDN) is a new area in network management. It is understood as using software to improve the network capabilities and intelligence. Autonomicity is one of proposed technologies, which also can improve network management capabilities. A scheme of the combination of OpenFlow based SDN and Autonomicity is proposed in this paper to introduce self-* attributes into OpenFlow Based SDN so that the network could be better controlled and operated efficiently.

PDB-based SLS decomposition in heterogeneous IP network

In order to provide QoS-assured service for end users, service providers (SP) must obtain sufficient network resource from network providers (NP). However, current network infrastructures belong to different NPs and are divided into a number of domains. SP may need to rely on more than one NP to get the connectivity. Thus the SLA between SP and NPs may span several domains with heterogeneous QoS technologies. Without knowing the network details, such as topology, infrastructure and QoS technology, SP is difficult to sign a proper SLA with a tradeoff between end-to-end QoS and his budget. A SLS (service level specification) decomposition service is proposed here to solve the problem. The service implementation uses distributed PDB information to conceal the network heterogeneity from SP, which acts as an indication of network performance for a certain QoS level packets. The service enables SP to get an optimized SLA and achieve inter-domain QoS without knowing the network details. A SLS Decomposition Service prototype is implemented and its feasibility is validated.

N3S-OLSR: Node-Status Self-Sensing Optimized Link-State Routing Protocols for MANET

In MANET, the severe instability feature produced by mobility and wireless nature leads to the frequent change of network topology and influences network performance. In this paper, we propose an improved routing protocol -- N3S-OLSR, which calculates MPR sets with combination of self-sensing information and hop count. Through self-sensing module, nodes obtain the network status information, and map them into two values - NS_COST and LINK_COST. N3S-OLSR exchanges network status information through extended Hello message, and calculates the MPR set with neighbors’ NS_COST and LINK_COST not only between node and its neighbors but also between its neighbors and its 2-hop neighbors. Simulation results show that, our protocol can provide better network performance than traditional OLSR.

Implementation of an ATM network and PSTN/N-ISDN interworking gateway

Broadband networks based on asynchronous transfer mode (ATM) have already been in commercial operation in some countries. The ATM has the capability of integrating various types of services into a single network. However, the traditional narrowband services still accounts for the major portion of the total telecommunication services. So it is necessary to implement the interworking function between the ATM network and PSTN/N-ISDN. We present a narrowband-broadband network interworking gateway (NB-IWG), in which we exploited the dynamic composite cell mechanism to adapt the voice traffic into ATM cells and implemented the signalling interworking between the narrowband and broadband network.

Design and implementation of an expert system on man-machine interface for the SPC switching system

It is very important to improve man-machine interface of computer system for the people. We know that the daily maintenance or management of SPC switching system requires many man-machine communications, but now many kinds of man-machine communications of SPC switching system are neither very easy nor very perceptive directly for the operators. This paper presents a user-friendly intelligent man-machine communication tool for SPC switching systems.<<ETX>>