Ehab S. Elmallah

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In this paper we prove two results on partitioning the edges of a planar graph into two partial k-trees, for fixed values of k. Interest in this class of partitioning problems arises since many intractable graph and network problems admit polynomial time solutions on k-trees and their subgraphs (partial k-trees). The first result shows that every planar(More)
Consider a communication network where each process needs to securely exchange messages with its neighboring processes. In this network, each sent message is encrypted using one or more symmetric keys that are shared only between two processes: the process that sends the message and the neighboring process that receives the message. A straightforward scheme(More)
The differentiated services (DiffServ) architecture for provisioning quality of service (QoS) in the Internet provides a flexible framework for supporting a variety of services in heterogeneous environments. The assured forwarding (AF) per hop behaviour is a means of providing differential treatment of various DiffServ classes through achieving higher(More)
Harnessing the time varying topological aspect of mobile ad hoc networks so as to support Quality of Service (QoS) measures is a challenging problem. In this paper we develop and investigate the use of a simple spatial probabilistic locality model to enhance the performance of current on-demand routing algorithms. To explore the applicability of our(More)
We consider a network where users can issue certificates that identify the public keys of other users in the network. The issued certificates in a network constitute a set of certificate chains between users. A user u can obtain the public key of another user v from a certificate chain from u to v in the network. For the certificate chain from u to v, u is(More)