RFC 3390 Increasing TCP ’ s Initial

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. 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 [RFC2119]. 1. TCP Modification This document obsoletes [RFC2414] and updates [RFC2581] 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).