Static routing

About: Static routing is a research topic. Over the lifetime, 25733 publications have been published within this topic receiving 576732 citations.

Modeling path duration distributions in MANETs and their impact on reactive routing protocols

Abstract: We develop a detailed approach to study how mobility impacts the performance of reactive mobile ad hoc network routing protocols. In particular, we examine how the statistics of path durations including probability density functions vary with the parameters such as the mobility model, relative speed, number of hops, and radio range. We find that at low speeds, certain mobility models may induce multimodal distributions that reflect the characteristics of the spatial map, mobility constraints and the communicating traffic pattern. However, this paper suggests that at moderate and high velocities the exponential distribution with appropriate parameterizations is a good approximation of the path duration distribution for a range of mobility models. Analytically, we show that the reciprocal of the average path duration has a strong linear relationship with the throughput and overhead of dynamic source routing (DSR), which is also confirmed by simulation results. In addition, we show how the mathematical expression obtained for the path duration distribution can also be used to prove that the nonpropagating cache hit ratio in DSR is independent of velocity for the freeway mobility model. These two case studies illustrate how various aspects of protocol performance can be analyzed with respect to a number of significant parameters including the statistics of link and path durations.

Integrated dynamic IP and wavelength routing in IP over WDM networks

Abstract: This paper develops an algorithm for integrated dynamic routing of bandwidth guaranteed paths in IP over WDM networks. By integrated routing, we mean routing taking into account the combined topology and resource usage information at the IP and optical layers. Typically, routing in IP over WDM networks has been separated into routing at the IP layer taking only IP layer information into account, and wavelength routing at the optical layer taking only optical network information into account. The motivation for integrated routing is the potential for better network usage, and this is a topic which has not been been studied extensively. We develop an integrated routing algorithm that determines (1) whether to route an arriving request over the existing topology or whether it is better to open new wavelength paths. Sometimes it is better to open new wavelength paths even if it feasible to route the current demand over the existing IP topology due to previously set-up wavelength paths. 2) For routing over the existing IP-level topology, compute "good" routes. (3) If new wavelength paths are to be set-up, determine the routers amongst which new wavelength paths are to be set-up and compute "good" routes for these new wavelength paths. The performance objective is the accomodation of as many requests as possible without requiring any a priori knowledge regarding future arrivals. The route computations account for the presence or absence of wavelength conversion capabilities at optical crossconnects. We show that the developed scheme performs very well in terms of performance metrics such as the number of rejected demands.

Routing design in operational networks: a look from the inside

Abstract: In any IP network, routing protocols provide the intelligence that takes a collection of physical links and transforms them into a network that enables packets to travel from one host to another. Though routing design is arguably the single most important design task for large IP networks, there has been very little systematic investigation into how routing protocols are actually used in production networks to implement the goals of network architects. We have developed a methodology for reverse engineering a coherent global view of a network's routing design from the static analysis of dumps of the local configuration state of each router. Starting with a set of 8,035 configuration files, we have applied this method to 31 production networks. In this paper we present a detailed examination of how routing protocols are used in operational networks. In particular, the results show the conventional model of "interior" and "exterior" gateway protocols is insufficient to describe the diverse set of mechanisms used by architects, and we provide examples of the more unusual designs and examine their trade-offs. We discuss the strengths and weaknesses of our methodology, and argue that it opens paths towards new understandings of network behavior and design.

Ip-based services for circuit-switched networks

Abstract: A mechanism for providing a connection from an IP-based network to a circuit-switched network, such as a GSM network is disclosed. A temporary routing number for the circuit-switched network, such as an E.164 number, is delivered to a user terminal, and a circuit-switched call leg is established from the user terminal to the IP-based network using the routing number. Thereby, IMS-services are provided for end users which are located in the radio access network not having sufficient QoS required for voice over IP. In the example of a conference call service, a request for a conference call may forwarded via a data channel or data path to an application server which provides that conference call service. The application server then selects a conference routing number and returns the routing number to the conference host terminal via the data channel. Using the received conference routing number, the conference host terminal can then set up a circuit-switched connection as a call leg of the conference call.