RAI (Remote Alarm Indication) ◆ PRI alarm, also known as Yellow signal. This alarm indicates a carrier failure.

RBOC (Regional Bell Operating Company) ◆ Thisreferstotheoriginal seven regional telephone companies created by the AT& T divesti- ture: Nynex, Bell Atlantic, Bell South, Southwestern Bell, US West, Pacific Telesis and Ameritech.

RD (Received Data) ◆ RS-232 (V.24) data signal, sent from the data communications equipment to the data terminal equipment on pin 3. (See RS-232.)

REN (Ringer Equivalence Number) ◆ A standard requirement of the FCC. For devices such as a telephone or answering machine. The REN requirement can be found on a label on the bottom of the analog device.

Repeater ◆ Device that acts as an amplifier. Also known as a Line Extender. This device is needed when the distance between the phone company's Central Office and your premises exceeds distance or dB loss limits.

RFC (Request for Comment) ◆ IETF (Internet Engineering Task Force) documents that contain proposed standards and specifications. RFCs can be either approved, or simply archived as historical recom- mendations.

RI (Ring Indicator) ◆ RS-232(V.24)controlsignal,sentfromthedata communications equipment to the data terminal equipment on pin 22. Indicates an incoming call is present. (See RS-232.)

RIP (Routing Information Protocol) ◆ Within IP networks, RIP is an interior gateway protocol used by routers and host systems to exchange information about reachable networks. RIP uses a distance-vectoring algorithm to establish and maintain network routes.

RJ-45◆ Standard 8-wire connector for IEEE 802.3 networks and some telephone applications.

Router ◆ Hardware device that connects two or more networks. A router determines where the destination computer is located, and then finds the best way to get there.

Routing ◆ Selecting the path to be taken by packets as they traverse the network.

Routing tables ◆ Stored in voice/data switches or routers to determine which of several possible paths will be taken through the net- work.

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