tuples, and sockets…

i used to always equate a tuple with a tcp socket; source/destination pair, protocol, port… especially in acl’s… ultimately a tuple is an ordered set of, things…

http://en.wikipedia.org/wiki/Network_socket

A network socket is an endpoint of an inter-process communication flow across a computer network. Today, most communication between computers is based on the Internet Protocol; therefore most network sockets are Internet sockets.

A socket API is an application programming interface (API), usually provided by the operating system, that allows application programs to control and use network sockets. Internet socket APIs are usually based on the Berkeley sockets standard.

A socket address is the combination of an IP address and a port number, much like one end of a telephone connection is the combination of a phone number and a particular extension. Based on this address, internet sockets deliver incoming data packets to the appropriate application process or thread.

stateful network firewalls, network address translators, and proxy servers keep track of active socket pairs. Also in fair queuing, layer 3 switching and quality of service (QoS) support in routers, packet flows may be identified by extracting information about the socket pairs. Raw sockets are typically available in network equipment and are used for routing protocols such as IGRP and OSPF, and in Internet Control Message Protocol (ICMP).

it’s etymology is based on -ple, which i always incorrectly  believed meant three, as in triple… but that’s not quite right when you consider, quadruple, quintuple, etc…

and this:

http://en.wiktionary.org/wiki/-tuple

-tuple

(mathematics) A tuple containing the specified number of terms.

a 20-tuple

and webster’s…http://dictionary.reference.com/browse/tuple?qsrc=2446

In functional languages, a data object containing two or more components. Also known as a product type or pair, triple, quad, etc. Tuples of different sizes have different types, in contrast to lists where the type is independent of the length. The components of a tuple may be of different types whereas all elements of a list have the same type.