RFC 4459 · INFORMATIONAL · 2006

MTU and Fragmentation Issues with In-the-Network Tunneling

Overview

RFC 4459, “MTU and Fragmentation Issues with In-the-Network Tunneling”, is an Informational document published in April 2006 by P. Savola. The canonical text is published by the RFC Editor.

Abstract

Tunneling techniques such as IP-in-IP when deployed in the middle of the network, typically between routers, have certain issues regarding how large packets can be handled: whether such packets would be fragmented and reassembled (and how), whether Path MTU Discovery would be used, or how this scenario could be operationally avoided. This memo justifies why this is a common, non-trivial problem, and goes on to describe the different solutions and their characteristics at some length. This memo provides information for the Internet community.

Abstract as published in the RFC, via rfc-editor.org.

What “Informational” means

Published for the general information of the community. It does not define an IETF standard and carries no standards-track status.

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