Technical data

previous intermediate system on the route, and passes them on to the destination
end system, or to the next intermediate system on the route.
internet
A shortened form of internetwork; a network of networks; interconnected TCP/IP
networks that function as one large virtual network. Differs from the Internet by
their lack of connectivity with the global Internet.
Internet
The worldwide network of networks and gateways that use the TCP/IP protocol
suite and function as one virtual network; provides universal connectivity and three
levels of network services: unreliable, connectionless packet delivery; reliable,
full-duplex stream delivery; and application level services such as electronic mail
that build on the first two. The Internet connects many universities, government
research labs, military installations, and private businesses.
Internet architecture
A four-layered communications model that consists of the following: Application
layer, Transport layer, Internet layer, and Network Interface layer.
Internet Architecture Board (IAB)
The technical body that oversees the development of the Internet suite of protocols
(TCP/IP). It has a research task force and an engineering task force, each
responsible for investigating a particular area.
Internet Autonomous System
A system that consists of a set of gateways, each of which can reach any other
gateway in the same system using paths by means of gateways only in that system.
The gateways of a system cooperatively maintain a routing database using an
interior gateway protocol.
Internet Control Message Protocol (ICMP)
An extension to the Internet Protocol; used by gateways to communicate with
the network software in hosts.
Internet header length
An IP header field that indicates the number of 32-bit words making up the
Internet header.
Internet layer
The layer in the TCP/IP network model where data is transferred between hosts
across networks. Also referred to as Network Interface layer.
Internet number
See IP address.
Internet Protocol (IP)
A connectionless, best-effort, packet-switching protocol that resides in the Internet
layer and has two major functions: internet addressing and fragmentation of
messages.
Internetwork
A collection of many different computing systems which communicate with each
other. The computing systems can include different hardware architectures,
operating systems, and network technologies.
interoperability
The ability of software and hardware on multiple machines from multiple vendors
to communicate meaningfully.
Glossary–22