This paper presents the design of a new Internet routing architecture (NIRA). In today’s Internet, users can pick their own ISPs, but once the packets have entered the network, the users have no control over the overall routes their packets take. NIRA aims at providing end users the ability to choose the sequence of Internet service providers a packet traverses. User choice fosters competition, which imposes an economic discipline on the market, and fosters innovation and the introduction of new services. This paper explores various technical problems that would have to be solved to give users the ability to choose: how a user discovers routes and whether the dynamic conditions of the routes satisfy his requirements, how to efficiently represent routes, and how to properly compensate providers if a user chooses to use them. In particular, NIRA utilizes a hierarchical provider-rooted addressing scheme so that a common type of domainlevel route can be efficiently represented by a pair of addresses. In NIRA, each user keeps track of the topology information on domains that provide transit service for him. A source retrieves the topology information of the destination on demand and combines this information with his own to discover end-to-end routes. This route discovery process ensures that each user does not need to know the complete topology of the Internet.

OF THE DISSERTATION Efficient Routing and Quality of Service Support for Ad Hoc Wireless Networks by Tsu-Wei Chen Doctor of Philosophy in Computer Science University of California, Los Angeles, 1998 Professor Mario Gerla, Chair One feature that distinguishes the ad hoc wireless network from traditional wired networks and PCS (personal communication network) is that all hosts in an ad hoc wireless network are allowed to move freely without the need for static access points. This distinct feature, however, presents a great challenge to the design of the routing scheme and the support of multimedia services, since the link quality and the network topology may be fast changing as hosts roam around. In this dissertation, we investigate the behaviors of existing routing algorithms. None of them satisfies the stringent requirements of ad hoc wireless networks. These requirements include: high accuracy, low overhead, scalability in a large network, the possibility of providing QoS routing, e...

Large-scale wireless sensor networks (WSNs) are highly vulnerable to attacks because they consist of numerous resource-constrained devices and communicate via wireless links. These vulnerabilities are exacerbated when WSNs have to operate unattended in a hostile environment, such as battlefields. In such an environment, an adversary poses a physical threat to all the sensor nodes. An adversary may capture any node, compromising criti-cal security data including keys used for encryption and authentication. Consequently, it is necessary to provide security services to these networks to ensure their survival. We propose a novel, self-organizing key management scheme for large-scale and long-lived WSNs, called Survivable and Efficient Clustered Keying (SECK). SECK provides adminis-trative services that ensures the survivability of the network. SECK is suitable for manag-ing keys in a hierarchical WSN consisting of low-end sensor nodes clustered around more capable gateway nodes. Using cluster-based administrative keys, SECK provides five ef-ficient security administration mechanisms: 1) clustering and key setup, 2) node addition, 3) key renewal, 4) recovery from multiple node captures, and 5) re-clustering. All of these

In an ad-hoc environment with no wired communication infrastructure, it is necessary that mobile hosts operate as routers in order to maintain the information about connectivity. However, with the presence of high mobility and low signal/interference ratio (SIR), traditional routing schemes for wired networks are not appropriate, as they either lack the ability to quickly reflect the changing topology, or may cause excessive overhead, which degrades network performance. Considering these restrictions, we propose a new scheme especially designed for routing in an ad-hoc wireless environments. We call this scheme "Global State Routing" (GSR), where nodes exchange vectors of link states among their neighbors during routing information exchange. Based on the link state vectors, nodes maintain a global knowledge of the network topology and optimize their routing decisions locally. The performance of the algorithm, studied in this paper through a series of simulations, reveals that this sche...