NASCOM

[2][3] Prior to the advent of NASCOM, the Minitrack network—used to track the flights of Sputnik, Vanguard, Explorer, and other early spacecraft—largely relied on military-supplied teletype lines which were limited to about 30 bits per second.

Scientific data from the Vanguard missions was recorded at ground stations onto magnetic tape, and air mailled to the control center at the Naval Research Laboratory.

Later, as NASA recruited personnel from military and industry, it began to accrue an in-house knowledge base for wide-band, real-time computer-based networks.

[2] NASCOM began taking shape in the early 1960s, and was formally established in 1964, under the administration of the recently formed Office of Tracking and Data Acquisition.

Specifications for the Mercury Network were issued on May 21, 1959, establishing a baseline with a mission control center in Cape Canaveral (later Houston), data convergence at Goddard, and switching stations overseas to provide redundancy and trunking over expensive transoceanic cables.

Voice capability was expanded to all MSFN, DSN, and other sites, and multiplexing of teletype messages was introduced at overseas switching centers.

By 1974, NASCOM was the largest broad-band, real-time communication network in the world, linking all the continents except for Asia and Antarctica, and allowing for a two-way "dialog" with spacecraft from a centralized mission control center.

[3] In its FY1995 Nascom System Development Plan, the NASA Communications Division underwent reorganization, with contractors taking over operations and maintenance roles previously performed by civil servants.

[7] As of 2007, NASCOM data blocks were considered a "legacy" protocol, and continued to be encapsulated in IP packets for transmission on the NASA Integrated Services Network (NISN).