Instead of firewalls and virus checkers, the company pitches a network that monitors individual data packets, shuts off rogue computers and isolates questionable users.

FORBES: Technology

Ken Silva, the security chief at VeriSign, which runs big chunks of the internet's domain-name system, advocates defences at the core of the network to tackle malicious data-packets before they reach their target.

ECONOMIST: Cyberwarfare

The Internet, by contrast, is a connectionless network designed for routing packets of data.

ECONOMIST: Internet telephony

Three years after sending those first packets of data, the network created by Metcalfe and Boggs had 100 machines on it.

BBC: Original Ethernet diagram, 3Com

Over the last 20 years, Cisco has come to dominate the business of routers and switches--the specialized computers that shuttle packets of data around a network, and form the backbone of the Internet--and about two thirds of its revenue comes from sales of those devices.

FORBES: Cisco Reaches High And Low

The outputs might be numbers represent complex data structures: images, sounds, network packets, etc.

FORBES: Software Is Just Math. Really.

Skype's so-called peer-to-peer technique involves the trick of distributing data packets to relatively precise ports on the network.

FORBES: Focus

Text, voice, and data will begin life as packets, travel through the network as packets, and arrive on customer devices as packets.

FORBES: AT&T Moves Dramatically Towards 'Internet Everywhere'

However, VOIP differs from the usual phone services in that it sends calls as digital packets of information over data networks rather than relying on a dedicated circuit-switched network.

ECONOMIST: Taking the battle online | The

But video poses real challenges, as it consumes considerably more bandwidth than both voice and data, and video quality degrades substantially, often unacceptably, when network congestion interrupts or delays individual packets in traffic streams.

FORBES: Bridging The Data Deluge Gap