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Information stored within a router that contains network path and status information.

It is used to select the most appropriate route to forward information along.

Routing Information Protocol

Routers periodically exchange information with one another so that they can

determine minimum distance paths between sources and destinations.

SNMP

Simple Network Management Protocol - The network management protocol of choice

for TCP/IP-based Internet.

SOCKET

(1) The Berkeley UNIX mechanism for creating a virtual connection between

processes.

(2) IBM term for software interfaces that allow two UNIX application programs to

talk via TCP/IP protocols.

Spanning-Tree Bridge Protocol (STP)

Spanning-Tree Bridge Protocol (STP) - Part of an IEEE standard. A mechanism for

detecting and preventing loops from occurring in a multi-bridged environment.

When three or more LAN'

s segments are connected via bridges, a loop can occur.

Because of a bridge forwards all packets that are not recognized as being local,

some packets can circulate for long periods of time, eventually degrading system

performance. This algorithm ensures only one path connects any pair of stations,

selecting one bridge as the '

root'

bridge, with the highest priority one as identifier,

from which all paths should radiate.

Spoofing

A method of fooling network end stations into believing that keep alive signals have

come from and returned to the host. Polls are received and returned locally at

either end

Static IP Address

A static IP address is an IP address permanently assigned to computer in a TCP/IP

network. Static IP addresses are usually assigned to networked devices that are

consistently accessed by multiple users, such as Server PCs, or printers. If you are

using your Router to share your cable or DSL Internet connection, contact your ISP to

see if they have assigned your home a static IP address. You will need that address

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during your Router'

s configuration.

Subnet

For routing purposes, IP networks can be divided into logical subnets by using a

subnet mask. Values below those of the mask are valid addresses on the subnet.

TCP

Transmission Control Protocol - The major transport protocol in the Internet suite of

protocols provides reliable, connection-oriented full-duplex streams.

TFTP

Trivial File Transfer Protocol. A simple file transfer protocol (a simplified version of

FTP) that is often boot diskless workstations and other network devices such as

routers over a network (typically a LAN).

Telnet

The virtual terminal protocol in the Internet suite of protocols - Allows users of one

host to log into a remote host and act as normal terminal users of that host.

Transparent bridging

The intelligence necessary to make relaying decisions exists in the bridge itself and is

thus transparent to the communicating workstations. It involves frame forwarding,

learning workstation addresses, and ensuring no topology loops exist (in conjunction

with the Spanning-Tree algorithm).

UDP

User Datagram Protocol - A connectionless transport protocol that runs on top of

TCP/IP'

s IP. UDP, like TCP, uses IP for delivery; however, unlike TCP, UDP

provides for exchange of datagram without acknowledgments or guaranteed delivery.

Best suited for small, independent requests, such as requesting a MIB value from an

SNMP agent, in which first setting up a connection would take more time than

sending the data.

UNI signaling

User Network Interface signaling for ATM communications.

Virtual Connection (VC)

A link that seems and behaves like a dedicated point-to-point line or a system that

delivers packets in sequence, as happens on an actual point-to-point network. In

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reality, the data is delivered across a network via the most appropriate route. The

sending and receiving devices do not have to be aware of the options and the route is

chosen only when a message is sent. There is no pre-arrangement, so each virtual

connection exists only for the duration of that one transmission.

WAN

Wide area network - A data communications network that spans any distance and is

usually provided by a public carrier (such as a telephone company or service

provider).