Nagle's algorithm: Difference between revisions

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'''Nagle's algorithm''' is a means of improving the efficiency of [[TCP/IP]] networks by reducing the number of packets that need to be sent over the network. It is named after John Nagle, thenwhilst employed at [[Ford Aerospace]]. and lately at [[Animats]].{{fact}}

Nagle's document, ''Congestion Control in IP/TCP Internetworks'' ([http://www.ietf.org/rfc/rfc896.txt RFC896]) describes what he called the 'small packet problem', where an application repeatedly emits data in small chunks, frequently only 1 [[byte]] in size. Since [[Transmission Control Protocol|TCP]] packets have a 40 byte header (20 bytes for TCP, 20 bytes for IPv4), this results in a 41 byte packet for 1 byte of useful information, a huge overhead. This situation often occurs in [[Telnet]] sessions, where most keypresses generate a single byte of data which is transmitted immediately. Worse, over slow links, many such packets can be in transit at the same time, potentially leading to [[congestion collapse]].