MTU discovery using TCP MSS and Discussion on MSS value in SYN reply
draft-bvenkat-mtu-tcpmss-03
| Document | Type |
Expired Internet-Draft
(individual)
Expired & archived
|
|
|---|---|---|---|
| Author | Balaji Venkat | ||
| Last updated | 1999-01-29 | ||
| RFC stream | (None) | ||
| Intended RFC status | (None) | ||
| Formats | |||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | Expired | |
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:
Abstract
Path MTU discovery as it exists now finds the least MTU of a given path. Traceroute through IP option [3] provides a method for finding the MTU on each hop using an ICMP message as a reply from the target host, with output link MTU in a portion of the message. The method proposed in this document intends to find the outbound MTU on each hop on an internet path, without using the ICMP message for traceroute. This mechanism intends to acheive the same goal as the traceroute through IP option, but through a different mechanism. Discovery of the MTU of each router on a internet path would serve as a valuable network debugging tool. The way in which it is proposed to be implemented, it has the advantage of being automatically supported by all of the routers that support the TCP layer. It has a couple of disadvantages that it generates quite a few TCP packets and the amount of time it takes to run to discover each MTU along the path is quite substantial. This document specifies the MTU discovery mechanism with the existing IP and TCP options and the ICMP message types that exist on all routers that support TCP layer in the internet. This method is suggested as an alternative to the Traceroute through IP option [3]. The intention is not to obsolete RFC 1393. This document also suggests that by default a reply SYN packet from a target host should include a MSS value that is derived from the MTU of the connected network of the outbound interface.
Authors
(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)