Interdomain Traffic Engineering Techniques to Overcome Undesirable Connectivity Incidents

Part 6: Poster Sessions; International audience; The importance of Internet availability is supported by the overwhelming dependence of government services and financial institutions upon said availability. Unfortunately, the Internet is facing different level of undesirable connectivity incidents. So, it is imperative to take serious measures in order to increase Internet connectivity resilience. We consider a scenario where a concerned region is facing an undesirable connectivity incident by its primary Internet Service Provider (ISP) which still advertises reachability to the concerned region. Assuming that connectivity to a secondary ISP is available, software is designed to implement different traffic engineering techniques in order to enhance internet connectivity resilience and send the traffic through the secondary ISP. The work is characterized by the implementation of these traffic engineering techniques in the laboratory through a detailed set of experiments. Document type: Part of book or chapter of boo

Vertical Handoff Characterization for SIP and mSCTP Based UMTS-WLAN Integration Solutions

It is desirable to integrate 3G Universal Mobile Telecommunication System (UMTS) and 802.11 wireless local area networks, especially at hot-spot locations such as hotels and airports. The efficiency of wireless data services can be maximized if the integration provides users with seamless roaming across the two types of networks. Seamless handoff between these two networks to maintain session continuity is a major challenge in WLAN-3G integration. To achieve this goal, integration architectures together with mobility solutions such mobile stream control transmission protocol (mSCTP) and session initiation protocol (SIP) have been proposed in the literature. In this paper, we implement through simulations an integration architecture and characterize the vertical handoff delay for both mobility solutions mSCTP and SIP as a function of network parameters. This study finds that mSCTP perform better in terms of handoff delay compared to SIP for the assumptions specified in this paper

Performance of UMTS/WLAN Integration at Hot-Spot Locations Using OPNET

Due to the many benefits provided by both the third-generation (3G) mobile networks and the IEEE 802.11 wireless local area networks (WLANs), it is desirable to integrate both types of networks. While studies specifying generic integration architectures are abundant, there are little or no studies that are dedicated for applications performance over such heterogeneous networks. Using simulations, this paper evaluates the performance of two 3G/WLAN integration schemes: loose and open coupling, together with two mobility management schemes: Mobile IP and mobile stream control transmission protocol (mSCTP) for an airport as a typical example of a hot-spot location. In addition, the evaluation is carried out for a wide range of application mixes consisting of FTP, HTTP and multimedia. Utilizing OPNET as the simulation platform and incorporating the required protocols to support our implementation of the Mobile IP and mSCTP, we generate a large matrix of performance figures for the 4 network configurations under all applications mixes considered. The results summarized in this paper indicate that integration methods considered have little impact on the application mixes studied in terms of delay but show that FTP and HTTP throughput is better with loose coupling scheme. Further, quantifying the handoff delay between the 3G and WLAN networks, the results indicate that a loose-couple integration solution together with Mobile IP provides the best performance

Asynchronous failure location and agreement algorithms for fiber-optic and for traditional networks with Byzantine links

Vita

Algorithms to locate switching faults in general synchronous fiber-optic networks

Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to [email protected], referencing the URI of the item.Includes bibliographical references.Not availabl

Optimal Asynchronous Agreement and Leader Election Algorithm for Complete networks with Byzantine Faulty Links

We consider agreement and leader election on asynchronous complete networks when the processors are reliable, but some of the channels are subject to failure. Fischer, Lynch, and Paterson have already shown that no deterministic algorithm can solve the agreement problem on asynchronous networks if any processor fails during the execution of the algorithm. Therefore, we consider only channel failures. The type of channel failure we consider in this paper is Byzantine failure, that is, channels fail by altering messages, sending false information, forging messages, losing messages at will, and so on. There are no restrictions on the behavior of a faulty channel. Therefore, a faulty channel may act as an adversary who forges messages on purpose to prevent the successful completion of the algorithm. Because we assume an asynchronous network, the channel delays are arbitrary. Thus, the faulty channels may not be detectable unless, for example, the faulty channels cause garbage to be sent. We present the first known agreement and leader election algorithm for asynchronous complete networks in which the processors are reliable but some channels may be Byzantine faulty. The algorithm can tolerate up to [n−22] faulty channels, where n is the number of processors in the network. We show that the bound on the number of faulty channels is optimal. When the processors terminate their corresponding algorithms, all the processors in the network will have the same correct vector, where the vector contains the private values of all the processors