NOTE: This charter is a snapshot of the 41st IETF Meeting in Los Angeles, California. It may now be out-of-date. Last Modified: 10-Feb-98
Chair(s):
Joseph Macker <macker@itd.nrl.navy.mil>
Scott Corson <corson@isr.umd.edu>
Routing Area Director(s):
Joel Halpern <jhalpern@newbridge.com>
Routing Area Advisor:
Joel Halpern <jhalpern@newbridge.com>
Mailing Lists:
General Discussion:manet@itd.nrl.navy.mil
To Subscribe: majordomo@itd.nrl.navy.mil
In Body: subscribe manet
Archive: ftp://manet.itd.nrl.navy.mil/pub/manet/manet.archive
Description of Working Group:
A "mobile ad hoc network" (MANET) is an autonomous system of mobile routers (and associated hosts) connected by wireless links--the union of which form an arbitrary graph. The routers are free to move randomly and organize themselves arbitrarily; thus, the network's wireless topology may change rapidly and unpredictably. Such a network may operate in a standalone fashion, or may be connected to the larger Internet.
The primary focus of the working group is to develop and evolve MANET routing specification(s) and introduce them to the Internet Standards track. The goal is to support networks scaling up to hundreds of routers. If this proves successful, future work may include development of other protocols to support additional routing functionality. The working group will also serve as a meeting place and forum for those developing and experimenting with MANET approaches.
The working group will examine related security issues around MANET. It will consider the intended usage environments, and the threats that are (or are not) meaningful within that environment.
Goals and Milestones:
Done |
|
Post as an informational Internet-Drafts a discussion of mobile ad-hoc networking and issues. |
Done |
|
Agenda bashing, discussion of charter and of mobile ad hoc networking draft. |
Oct 97 |
|
Post Internet-Drafts for candidate protocols. |
Done |
|
Discuss proposed protocols and issues. Redefine charter. |
Feb 98 |
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Submit Internet-Draft of MANET Routing Protocol Performance Issues and Evaluation Considerations to IESG for publication as an informational RFC. |
Feb 98 |
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Submit Internet-Draft of MANET Terminology Document to IESG for publication as an informational RFC. |
Mar 98 |
|
Revise candidate I-Ds as appropriate |
Aug 98 |
|
Target demonstration of working software prototypes |
Mar 99 |
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Target interoperable implementations, and review any required protocol modifications. Publish as I-D |
Dec 99 |
|
Document and submit protocol specification(s) to IESG as proposed standards |
Internet-Drafts:
· Mobile Ad hoc Networking (MANET): Routing Protocol Performance Issues and Evaluation Considerations
· Mobile Ad Hoc Networking Terminology
· The Zone Routing Protocol (ZRP) for Ad Hoc Networks
· Ad Hoc On Demand Distance Vector (AODV) Routing
· Temporally-Ordered Routing Algorithm (TORA) Version 1 Functional Specification
· An Internet MANET Encapsulation Protocol (IMEP) Specification
· The Dynamic Source Routing Protocol for Mobile Ad Hoc Networks
No Request For Comments
Minutes of Mobile Ad-hoc Networks (manet) Working Group
The MANET WG met for two hours, and the meeting began with five presentations:
1) Phil Papadopoulos (ORNL) gave an update regarding the IMEP protocol and described a group coloring mechanism for providing one-hop, point-to-multipoint, selective repeat for broadcast traffic. The mechanism uses a combination of sequence number and color to manage a current one-hop delivery neighborhood. There is no working group consensus regarding the IMEP draft, only its authors at this phase. The intent of IMEP is to supply a network support sublayer to provide support for multiple MANET routing policies, and is intended to become a working group document without an explicit author list--only a list of contributors and a general editor. Most of what was presented in the talk is not in the current draft, but will appear in a revised version shortly.
2) Marc Pearlman (Cornell) gave an update regarding recent work on ZRP and presented some simulation performance results. Several mechanisms were described including query detection (a method to terminate requests that come in to previously queried nodes--intermediate nodes "listen in" and may terminate requests), and "selective bordercasting" which computes a smaller set of inner periphery nodes required to get a given set of outer nodes covered (can be viewed as a multihop version of multipoint relaying, only the computation is NP-hard). Presented a loose description of the call to mobility ratio, but did not describe what it is or how it is measured.
3) Mario Gerla (UCLA) presented recent results in contention-based MAC layer/TCP interaction to give the group some insight as to how TCP might perform in MANETs. Tests were run on a 7 node tandem network using both CSMA/CA and FAMA with error-free channels. TCP was seen to perform better with fixed (as opposed to adaptive) window sizes. The well-known TCP behavior of being unfair to long connections competing with shorter connections was shown to exist in a dramatic fashion over contention-based MAC schemes. Future work will examine approaches such as the snoop protocol, ECN and fair queuing at the link layer to improve performance.
4) Amir Qayyum (INRIA) described the concept of multipoint relaying--a simple mechanism for efficient flooding in MANETs--which is proposed as an optional mode for use in IMEP. Essentially, MPR is a distributed algorithm wherein nodes periodically exchange their one-hop neighbors sets thereby enabling each other to compute the two-hop neighborhood. Nodes then select a subset of their one-hop neighbors to serve as MPR's which forward their traffic to the two-hop nodes. This enables efficient implementation of flooding in MANETs and should be used when the bandwidth savings in flooding overhead reduction from using MRP justifies the cost of the periodic message exchanges.
5) Dave Johnson (CMU) presented the DSR draft which presents a general protocol for performing dynamic source routing with multiple options intended to improve performance. The protocol is described as being suitable for small networks--5 to 10 hops typical traversal. He also presented the recent modification of DSR to support multiple interfaces per router. The addressing scheme is flat, but is not pure IP-level addressing with an IP address per interface but, rather, one IP address per router with interfaces indexed by 8-bit numbers. The approach uses IPv6-style header options and requires modification for use in IPv4 kernels. He also briefly mentioned work underway in NS-2 to support MANET routing studies that should be available for group use by summer.
General Discussion:
There was group consensus that the principal reason for using IP-layer routing in MANETs was to support an IP routing topology or "fabric" consisting of multiple, heterogeneous physical layer topologies, or perhaps even multiple topologies of the same technology using different frequencies.
Discussions then followed regarding node architectures, subnet address advertisement and transport/network layer interaction. There was no consensus reached on any of these subjects before the meeting had to be closed due to a lack of time, however the general feeling regarding TCP/network interaction was the TCP modifications would be a last resort and the MANET technology should be designed to support TCP as well as possible. It was suggested that these subjects be raised on the mailing list.
The Dynamic Source Routing Protocol for Mobile Ad Hoc Networks
TCP Simulation Experiment