Pre-Congestion Notification (PCN) Architecture

This document describes a general architecture for flow admission and termination based on pre-congestion information in order to protect the quality of service of established, inelastic flows within a single Diffserv domain.\u

Recursive SDN for Carrier Networks

Control planes for global carrier networks should be programmable (so that new functionality can be easily introduced) and scalable (so they can handle the numerical scale and geographic scope of these networks). Neither traditional control planes nor new SDN-based control planes meet both of these goals. In this paper, we propose a framework for recursive routing computations that combines the best of SDN (programmability) and traditional networks (scalability through hierarchy) to achieve these two desired properties. Through simulation on graphs of up to 10,000 nodes, we evaluate our design's ability to support a variety of routing and traffic engineering solutions, while incorporating a fast failure recovery mechanism

Recovery modeling in MPLS networks

Transmission of QoS based traffic over packet switched network typically requires resource reservation or differentiated treatment to guarantee an acceptable level of performance. But it is also essential to bound the disruption caused by failure of nodes or links for a real time traffic to a limit that is acceptable by the application. In this paper, a simulation platform models the impact of the MPLS recovery/protection schemes on the QoS traffic parameters including disruption time and number of out of order packets arriving at the destination. The simulation considers measures to alleviate drawbacks caused by recovery process

Label Space Reduction in MPLS Networks: How Much Can A Single Stacked Label Do?

Most network operators have considered reducing LSR label spaces (number of labels used) as a way of simplifying management of underlaying virtual private networks (VPNs) and therefore reducing operational expenditure (OPEX). The IETF outlined the label merging feature in MPLS-allowing the configuration of multipoint-to-point connections (MP2P)-as a means of reducing label space in LSRs. We found two main drawbacks in this label space reduction a)it should be separately applied to a set of LSPs with the same egress LSR-which decreases the options for better reductions, and b)LSRs close to the edge of the network experience a greater label space reduction than those close to the core. The later implies that MP2P connections reduce the number of labels asymmetricall

Multi-domain crankback operation for IP/MPLS & DWDM networks

Network carriers and operators have built and deployed a very wide range of networking technologies to meet their customers needs. These include ultra scalable fibre-optic backbone networks based upon dense wavelength division multiplexing (DWDM) solutions as well as advanced layer 2/3 IP multiprotocol label switching (MPLS) and Ethernet technologies as well. A range of networking control protocols has also been developed to implement service provisioning and management across these networks. As these infrastructures have been deployed, a range of new challenges have started to emerge. In particular, a major issue is that of provisioning connection services between networks running across different domain boundaries, e.g., administrative geographic, commercial, etc. As a result, many carriers are keenly interested in the design of multi-domain provisioning solutions and algorithms. Nevertheless, to date most such efforts have only looked at pre-configured, i.e., static, inter-domain route computation or more complex solutions based upon hierarchical routing. As such there is significant scope in developing more scalable and simplified multi-domain provisioning solutions. Moreover, it is here that crankback signaling offers much promise. Crankback makes use of active messaging techniques to compute routes in an iterative manner and avoid problematic resource-deficient links. However very few multi-domain crankback schemes have been proposed, leaving much room for further investigation. Along these lines, this thesis proposes crankback signaling solution for multi-domain IP/MPLS and DWDM network operation. The scheme uses a joint intra/inter-domain signaling strategy and is fully-compatible with the standardized resource reservation (RSVP-TE) protocol. Furthermore, the proposed solution also implements and advanced next-hop domain selection strategy to drive the overall crankback process. Finally the whole framework assumes realistic settings in which individual domains have full internal visibility via link-state routing protocols, e.g., open shortest path first traffic engineering (OSPF-TE), but limited \u27next-hop\u27 inter-domain visibility, e.g., as provided by inter-area or inter-autonomous system (AS) routing protocols. The performance of the proposed crankback solution is studied using software-based discrete event simulation. First, a range of multi-domain topologies are built and tested. Next, detailed simulation runs are conducted for a range of scenarios. Overall, the findings show that the proposed crankback solution is very competitive with hierarchical routing, in many cases even outperforming full mesh abstraction. Moreover the scheme maintains acceptable signaling overheads (owing to it dual inter/intra domain crankback design) and also outperforms existing multi-domain crankback algorithms.\u2

Comparison Analysis Of Recovery Mechanism At Mpls Network

Multi-protocol Label Switching (MPLS) has become an attractive technology of choice for Internet backbone service providers.  MPLS features the ability to perform traffic engineering and provides support for Quality of Service traffic provisioning. To deliver reliable service, MPLS requires a set of procedures to provide protection for the traffic carried on Label Switched Paths (LSP). In this case Lable Switched Routers (LSRS) supports recovery mechanism when failure happened in the network.This paper studied about performance from usage of different techniques that can be used to reroute traffic faster then  the current IP rerouting methods in the case of a failure in a network. Local rerouting, fast reroute one to one backs up, Haskin, PSL oriented path protection and 1+1 path protection recovery mechanism was compared by given of aggregate traffic which has self-similarity character. Packet drop, rejection probability, recovery time, service disruption time and pre-reserved resources backup will be made as comparator parameter with various bitrate and different position of link failure. Packet loss, rejection probability, recovery time and service disruption time at five recovery mechanisms influenced by position of link failure to ingress. 1+1 path protection mechanism has least packet drop, but costliest way to do recovery in the case of usage resources, as traffic is sent simultaneously in two paths which disjoint. Fast reroute one to one backup is quickest way to operate protection switching recovery after 1+1 path protection mechanism. Keywords: MPLS, recovery, rerouting, self-similar traffic, protection switchingDOI:http://dx.doi.org/10.11591/ijece.v1i2.8

Traffic engineering and path protection in MPLS virtual private networks

Traffic Engineering (TE) attempts to establish paths for the flow of data in a network so as to optimize the resource utilization and maximize the network performance. One of the main goals of Traffic Engineering is to bring about efficient and reliable network operations. Constraint based routing is the key to Multiprotocol label switching TE. Constraint based routing helps to manage traffic paths within a MPLS network and allows for traffic to flow along certain desired paths. MPLS also supports explicit routing thus providing TE capabilities. MPLS TE enables resiliency and reliability to be built into networks, thus increasing the value and availability of the network. TE is deployed in MPLS networks by providing TE extensions to interior gateway protocols like OSPF and IS-IS. MPLS creates a connection oriented model over the traditional connectionless framework of IP based networks. This connection oriented model helps to overcome several shortcomings of the IP network and also provide the necessary framework to give quality guarantees to IP traffic. Quality of Service (QoS) can be built into MPLS networks where TE is used. MPLS has made significant progress in recent years and is used for deployment of networks all over the world. In this thesis, we propose several constraint-based routing algorithms for MPLS based VPN\u27s. Our algorithms support routing of both Quality of Service (QoS) and BE traffic over the MPLS network. We have implemented a route based and a link based approach for routing of QoS and BE traffic. We also implement the 1 + 1 and 1 : 1 link disjoint and node disjoint path protection mechanisms for the QoS traffic. We study the effect of the various parameters used in our equations such as epsilon, granularity, earning rate and hop count. The problem is formulated as a multicommodity flow (MCF) problem and is solved using the optimization tool - ILOG CPLEX. Our approach is scalable to large networks having a number of VPN\u27s