abc

The letter for today in the Networking ABC's is the letter "N".  For "N", there are NATs, netmasks, and NNTP servers, but I opted for a word that's common to those who have dug into the implementations of TCP stacks, but may not be known to the rest of the human race.  This week's word is Nagle's Algorithm.  Without it, the web would be a much slower place.

"N" is for Nagle's Algorithm

tcp-connection-termination

Nagle's Algorithm

Pronounced Nay-gullz Al-guh-rith-uh-m

Nagle's algorithm, named after John Nagle, 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. 

Since TCP packets have a 40 byte header (for ipv4 networks), this results in a 41 byte packet for 1 byte of useful information.

Defined in RFC896, Nagle's algorithm works by coalescing a number of small outgoing messages and sending them all at once.