IP version 6 #IPv6# is being designed within the IETF as a replacement for the currentversion of the IP protocol used in the Internet #IPv4#. Wehave designed protocol enhancements for IPv6, known as Mobile IPv6, that allow transparent routing of IPv6 packets to mobile nodes, taking advantage of the opportunities made possible by the design of a new version of IP.InMobile IPv6, each mobile node is always identi#ed by its home address, regardless of its current point of attachment to the Internet. While away from its home IP subnet, a mobile node is also associated with a careof address, which indicates the mobile node's current location. Mobile IPv6 enables any IPv6 node to learn and cache the care-of address associated with a mobile node's home address, and then to send packets destined for the mobile node directly to it at this care-of address using an IPv6 Routing header.

We present detailed measurements of various processing overheads of the TCP/IP and UDP/IP protocol stacks on a DECstation 5000/200 running the Ultrix 4.2a operating system. These overheads include data-touching operations, such as the checksum computation and data movemen ~ which are well known to be major time consumers. In this stud y, we also considered overheads due to non-data touching operations, such as network buffer manipulation, protocol-specific processing, operating system functions, data structure manipulations (other than network buffers), and error checking. We show that when one considers realistic message size dktributions, where the majority of messages are small, the cumulative time consumed by the nondata touching overheads represents the majority of processing time. We assert that it will be difficult to significantly reduce the cumulative processing time due to non-data touching overheads. The goal of this study is to determine the relative importance of various processing overheads in network software, in particular, the TCP/IP and UDPAP protocol stacks. In the prrsg significant focus has been placed on maximizing throughput noting that “data

We present the design, implementation, and evaluation of Mobile*IP, a set of IP-based protocols and mechanisms to support host mobilitythroughout the Internet. The design requires changes only in the mobile hosts and their special routers; leaves transport and higher protocols unaffected, and requires no changes in the device drivers for individual interfaces. No modifications whatsoever are needed in non-mobile hosts and routers, the system scales well, and has no single points of failure. We have implemented Mobile*IP under Mach 2.6, and the code is readily portable to any version of Unix that uses Berkeley networking code. 1 Introduction Motivation The continuing drop in prices and increase in functionality of personal, portable computers, the increasing availability of wireless networking options as well as wide-area research and commercial networking offerings, and an increased desire of users to carry these systems and connections with them while they travel, suggests a market...

We present a link layer protocol called the Multi-radio Unification Protocol or MUP. On a single node, MUP coordinates the operation of multiple wireless network cards tuned to non-overlapping frequency channels. The goal of MUP is to optimize local spectrum usage via intelligent channel selection in a multihop wireless network. MUP works with standard-compliant IEEE 802.11 hardware, does not require changes to applications or higher-level protocols, and can be deployed incrementally. The primary usage scenario for MUP is a multihop community wireless mesh network, where cost of the radios and battery consumption are not limiting factors. We describe the design and implementation of MUP, and analyze its performance using both simulations and measurements based on our implementation. Our results show that under dynamic traffic patterns with realistic topologies, MUP significantly improves both TCP throughput and user perceived latency for realistic workloads. 1.

Mobile IP has been designed within the IETF to serve the needs of the burgeoning population of mobile computer users who wish to connect to the Internet and maintain communications as they move from place to place. The basic protocol is described, with details given on the three major component protocols: Agent Advertisement, Registration, and Tunneling. Then, route optimization procedures are outlined, and further topics of currentinterest are described.

We present PLANet: an active network architecture and implementation. In addition to a standard suite of Internetlike services, PLANet has two key programmability features: 1. all packets contain programs 2. router functionality may be extended dynamically Packet programs are written in our special purpose programming language PLAN, the Packet Language for Active Networks, while dynamic router extensions are written in Caml, a byte-code-interpreted dialect of ML. Currently,

Abstract- Host mobility is becoming an important issue due to the recent proliferation of notebook and palmtop computers, the development of wireless network interfaces, and the growth in global internetworking. This paper describes the design and implementation of a mobile host protocol, called the Internet Mobile Host Protocol (IMHP), that is compatible with the TCPDP protocol suite, and allows a mobile host to move around the Inter-net without changing its identity. In particular, IMHP provides host mobility over both the local and wide area, while remaining transparent to the user and to other hosts communicating with the mobile host. IMHP features route optimization and integrated authentication of all management packets. Route optimization allows a node to cache the location of a mobile host and to send future packets directly to that mobile host. By authenticating all management packets, IMHP guards against possible attacks on packet routing to mobile hosts, including the interception or redirection of arbitrary packets within the network. A simple new authentication mechanism is introduced that preserves the level of security found in the Internet today, while accommodating the transition to stronger authentication based on public key cryptog-raphy or shared keys that may either be manually administered or provided by a future Internet key management protocol. I.

this document should not be interpreted as representing the official policies, either expressed or implied, of the AAUW, AFOSR, ARPA, NSF, or the U.S. government.

Topology Dissemination Based on Reverse-Path Forwarding (TBRPF) is a proactive, link-state routing protocol designed for mobile ad-hoc networks, which provides hop-by-hop routing along shortest paths to each destination. Each node running TBRPF computes a source tree (providing paths to all reachable nodes) based on partial topology information stored in its topology table, using a modification of Dijkstra's algorithm. To minimize overhead, each node reports only *part* of its source tree to neighbors. TBRPF uses a combination of periodic and differential updates to keep all neighbors informed of the reported part of its source tree. Each node also has the option to report additional topology information (up to the full topology), to provide improved robustness in highly mobile networks. TBRPF performs neighbor discovery using "differential" HELLO messages which report only *changes* in the status of neighbors. This results in HELLO messages that are much smaller than those of other link-state routing protocols such as OSPF.

Abstract — We present a set of simple techniques for key establishment over a radio link in peer-to-peer networks. Our approach is based on the Diffie-Hellman key agreement protocol, which is known to be vulnerable to the “man-in-the-middle” attack if the two users involved in the protocol do not share any authenticated information about each other (e.g., public keys, certificates, passwords, shared keys, etc.) prior to the protocol execution. In this paper, we solve the problem by leveraging on the natural ability of users to authenticate each other by visual and verbal contact. We propose three techniques: the first is based on visual comparison of short strings, the second on distance bounding, and the third on integrity codes; in each case, the users do not need to enter any password or other data, nor do they need physical or infra-red connectivity between their devices. We base our analysis on a well-established methodology that leads us to a rigorous modularization and a thorough robustness proof of our proposal.