TFTP Windowsize Option (RFC7440)
Original Publication Date: 2015-Jan-01
Included in the Prior Art Database: 2015-Jan-24
Internet Society Requests For Comment (RFCs)
TFTP is virtually unused for Internet transfers today, TFTP is still massively used in network boot/installation scenarios including EFI (Extensible Firmware Interface). TFTP's inherently low transfer rate has been, so far, partially mitigated by the use of the blocksize negotiated extension [RFC2348]. Using this method, the original limitation of 512-byte blocks are, in practice, replaced in Ethernet environments by blocks no larger than 1468 Bytes to avoid IP block fragmentation. This strategy produces insufficient results when transferring big files, for example, the initial ramdisk of Linux distributions or the PE images used in network installations by Microsoft WDS/MDT/SCCM. Considering TFTP looks far from extinction today, this document presents a negotiated extension, under the terms of the "TFTP Option Extension" [RFC2347], that produces TFTP transfer rates comparable to those achieved by modern file transfer protocols.
Internet Engineering Task Force (IETF) P. Masotta Request for Comments: 7440 Serva Category: Standards Track January 2015 ISSN: 2070-1721
TFTP Windowsize Option
The "Trivial File Transfer Protocol" (RFC 1350) is a simple, lockstep, file transfer protocol that allows a client to get or put a file onto a remote host. One of its primary uses is in the early stages of nodes booting from a Local Area Network (LAN). TFTP has been used for this application because it is very simple to implement. The employment of a lockstep scheme limits throughput when used on a LAN.
This document describes a TFTP option that allows the client and server to negotiate a window size of consecutive blocks to send as an alternative for replacing the single-block lockstep schema. The TFTP option mechanism employed is described in "TFTP Option Extension" (RFC 2347).
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741.
Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc7440.
Masotta Standards Track [Page 1]
RFC 7440 TFTP Windowsize Option January 2015
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Table of Contents
1. Introduction ....................................................2 2. Conventions Used in This Document ...............................3 3. Windowsize Option Specification .................................3 4. Traffic...