Raymond B. Jennings

A study of Internet instant messaging and chat protocols

Instant messaging (IM) and network chat communication have seen an enormous rise in popularity over the last several years. However, since many of these systems are proprietary, little has been described about the network technology behind them. This analysis helps bridge this gap by providing an overview of the available features, functions, system architectures, and protocol specifications of the three most popular network IM protocols: AOL Instant Messenger, Yahoo! Messenger, and Microsoft Messenger. We describe common features across these systems and highlight distinctions between them. Where possible, we discuss the advantages and disadvantages of different technical approaches used in these systems to support different features and functions. We also briefly discuss ongoing efforts to standardize IM and chat-based protocols in IETF and other standards bodies

Policy Based SLA Management in Enterprise Networks

The Differentiated Services Architecture defines the mechanisms that are needed to offer multiple classes of services in an IP network. While this model offers significant scaling advantages over the signaling-oriented approach of Integrated Services, the management of a differentiated services network remains a complex problem. Since the operation of a differentiated network involves numerous access routers, core routers and servers, a consistent operation is difficult to achieve by independently configuring each device. In this paper, we explore a scheme to enable a network administrator to manage and configure DiffServ networks from a central location and also abstract away the specific details of device configuration, and allow him/her to express the management of the network in terms of application-oriented performance metrics. This leads to a simplification of network management task, which can be exploited to support business needs of an enterprise network, such as honoring Service Level Agreements provided to its customers.