Research On Port-based Packet Switching And QoS Routing

With the rapid development of network applications, Internet is becoming a global information infrastructure, which is working as a transport network to deliver multiple types of data including many new real-time multimedia applications. To cope with ever-increasing traffic demands, network should increase transmission bit rate and provide QoS guarantee for network traffic. Internet Protocol (IP) is the core of Internet architecture, its intrinsic shortcomings make Internet can not meet the service demands, that is (1) IP address overloads with semantics of identify, location and route identifier;(2) IP switches provide connectless delivery for packets. These designing principles have deep implications for network scalability, QoS guarantee, high-speed packet forwarding, power consumption, etc.We studied the network architecture which separates the control and forwarding plane. A connection-oriented low-complexity packet forwarding technology was proposed in forwarding plane, as well as the corresponding QoS routing protocol in control plane. The main research points and innovations in this dissertation are outlined as follow:1. A port/interface-based route encoding called Vector Address (VA) is proposed in forwarding plane. The encoding operation and its packet forwarding scheme (VS, Vector Switching) is presented. VA is a network path represented by a sequence of Port/interface Indexes (PI) which is an index number assigned to a fabric port/interface. Every PI offers its available bits, which is a short, variable-length, local value, to VA showing the packet how to reach an intermediate node’s output interface, till reaching the destination. Under VS mechanism based on PI, table lookup is not needed to forward a packet through a node. A PI makes intermediate nodes can not recognize the whole path’s VA or source/destination’s identity, so as to VA is scalable and secure. VA is a connection-oriented route identifier, which can implement explicit routing well and improve network QoS performance.2. An efficient packet switching framework called Vector Label Switching (VLS) for core Internet based on VA is proposed. VLS separates control and forwarding planes. The control plane assigns PIs to interfaces/ports and establishes VA between pairs of edge routers. The forwarding plane forwards packets from ingress router of core network to egress router. We implement the forwarding plane by NetFPGA and Linux system respectively. The routing table is not needed to be store and lookup on line-card. The analysis results show that VS enhance the energy-effect of routers and improves their performance with high flexibility in deployment of VLS.3. A QoS-guaranteed network framework is proposed by employing DiffServ-aware Traffic Engineering (DS-TE) in VLS architecture. The framework uses RSVP-TE (Resource ReSerVation Protocol-Traffic Engineering) protocol to establish VA and reserve bandwidth in control plane. In forwarding plane, it introduces differential switching to VS. In bandwidth management, link use Russian Doll Model (RDM) to allocate resource for traffic transmitting; an admission control algorithm and a bandwidth preemption algorithm is presented cooperating with the link allocation. The simulation results show that the framework guarantees QoS of traffic with a good fairness and efficiency; it improves the throughput of VLS.4. An optical code (OC)-based label switching scheme called Optical Code-based Vector Address-labeled (OCVA-labeled) switching, which carries all routing information in the packet header like VS, is proposed optical packet switch (OPS) networks. In the scheme, a forwarding path in network is composed of all OCs of passed interfaces on the path. An OC is assigned locally by a router/switch to its own output interface as an index number. Under OCVA-labeled mechanism, packet header re-writing (code conversion) is not required, which can make intermediate nodes much simpler. It also reduces the size of OC set required in the whole optical network, mitigating affect from MAI. The simulation results show OCVA-labeled switching reduces the OC recognition error as well as packet blocking rate of the whole network.