RFC 1948 · INFORMATIONAL · 1996

Defending Against Sequence Number Attacks

Overview

RFC 1948, “Defending Against Sequence Number Attacks”, is an Informational document published in May 1996 by S. Bellovin. It has been obsoleted by RFC 6528 — refer to the newer document for the authoritative version. The canonical text is published by the RFC Editor.

Abstract

IP spoofing attacks based on sequence number spoofing have become a serious threat on the Internet (CERT Advisory CA-95:01). While ubiquitous crypgraphic authentication is the right answer, we propose a simple modification to TCP implementations that should be a very substantial block to the current wave of attacks. This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind.

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.

Read this RFC

The canonical text of RFC 1948 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
Obsoleted by
RFC 6528
Other RFCs from 1996

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