IBM VNET

VNET is an international computer networking system deployed in the mid 1970s and still in current, but highly diminished use. It was developed inside IBM, and provided the main email and file-transfer backbone for the company throughout the 1980s and 1990s. Through it, a number of protocols were developed to deliver e-mail amongst time sharing computers over alternate transmission systems.

VNET was first deployed as a private host to host network among CP/67 and VM/370 mainframes beginning before 1975. It was based on RSCS, a virtual machine based communications program. RSCS used synchronous data link protocols, not SNA/SDLC, to support file to file transfer among virtual machine users. The first several nodes included Scientific Centers and Poughkeepsie, New York lab sites.

Broadband Internet access

Broadband Internet access, often shortened to just broadband, is high data rate Internet access—typically contrasted with dial-up access over a modem.

Dial-up modems are generally only capable of a maximum bitrate of 56 kbit/s (kilobits per second) and require the full use of a telephone line—whereas broadband technologies supply at least double this bandwidth and generally without disrupting telephone use.

Although various minimum bandwidths have been used in definitions of broadband, ranging up from 64 kbit/s up to 1.0 Mbit/s, the 2006 OECD report is typical by defining broadband as having download data transfer rates equal to or faster than 256 kbit/s, while the United States FCC, as of 2008, defines broadband as anything above 768 kbit/s. The trend is to raise the threshold of the broadband definition as the marketplace rolls out faster services each year.

Voice over Internet Protocol

Voice over Internet Protocol (VoIP, IPA: /vɔɪp/) is a general term for a family of transmission technologies for delivery of voice communications over IP networks such as the Internet or other packet-switched networks. Other terms frequently encountered and synonymous with VoIP are IP telephony, Internet telephony, voice over broadband (VoBB), broadband telephony, and broadband phone.

VoIP systems usually interface with the traditional public switched telephone network (PSTN) to allow for transparent phone communications worldwide

VoIP systems employ session control protocols to control the set-up and tear-down of calls as well as audio codecs which encode speech allowing transmission over an IP network as digital audio via an audio stream. Codec use is varied between different implementations of VoIP (and often a range of codecs are used); some implementations rely on narrowband and compressed speech, while others support high fidelity stereo codecs.