The main architectural problem with the current inter-domain routing model is the overloading of IP addresses due to their use for identification, location, and forwarding. This makes it hard to support the need for multi-homing, traffic engineering, and mobility while maintaining address hierarchy that is essential for scalable routing. Thus, there is a need to separate identifiers from locators. In this paper we identify architectural and protocol changes in addressing and routing needed to provide major improvements in scalability. We design a corresponding protocol solution (Address-Identifier Mapping System — AIMS) based on separation of identification and addressing, and a mechanism for mapping ID to address.

An architecture and implementation which support an interface to the X.400 mail environment using the full open-systems communications protocols for a portable computer are described. The implementation is designed to be used over a cellular radio telephone network. The portable computer is used to implement the user agent interface of the CCITT X.413 (1988) message store. A full set of security facilities, designed for use with interpersonal messaging (IPM), is included in the architecture. A number of important issues are discussed regarding the placement and management of keys for the IPM security, as well as authentication between the user and the portable computer and between the user agent and the message store. To support the use of the CCITT message-store model, it was necessary to implement a full protocol stack for open systems interconnection on the portable computer. The design and the author's experiences are described.>

Abstract The real problems of network interconnection lie in the management of heterogeneity. The heterogeneity is not confined to the mechanical protocols but to much wider issues such as service philosophy (connection‐orientated vs connectionless), addressing, routing, applications models, management facilities and the foresight of the network designers in allowing for interconnection with alien networking systems. This paper describes a system which interconnects two heterogeneous networking environments through a third (local) system. Application layer relaying was chosen to provide the services of computer mail and remote terminal access. The interconnection architecture uses special network front‐ends and a local area network to provide a flexible and manageable system. A transport service interface is used to provide functional separation between the front‐ends and general purpose computers, including the relays.

This paper describes a distributed architecture for the flexible interconnection of heterogeneous networks with a number of mini- and micro computers, in a research environment. The interconnected networks include the DARPA Internet, which uses the DoD protocols, and the X25-based networks PSS and SERCNET.