RFC 3390 (rfc3390) - Page 1 of 15
Increasing TCP's Initial Window
Alternative Format: Original Text Document
Network Working Group M. Allman
Request for Comments: 3390 BBN/NASA GRC
Obsoletes: 2414 S. Floyd
Updates: 2581 ICIR
Category: Standards Track C. Partridge
BBN Technologies
October 2002
Increasing TCP's Initial Window
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2002). All Rights Reserved.
Abstract
This document specifies an optional standard for TCP to increase the
permitted initial window from one or two segment(s) to roughly 4K
bytes, replacing RFC 2414. It discusses the advantages and
disadvantages of the higher initial window, and includes discussion
of experiments and simulations showing that the higher initial window
does not lead to congestion collapse. Finally, this document
provides guidance on implementation issues.
Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC 2119].
1. TCP Modification
This document obsoletes [RFC 2414] and updates [RFC 2581] and specifies
an increase in the permitted upper bound for TCP's initial window
from one or two segment(s) to between two and four segments. In most
cases, this change results in an upper bound on the initial window of
roughly 4K bytes (although given a large segment size, the permitted
initial window of two segments may be significantly larger than 4K
bytes).
Allman, et. al. Standards Track