C

call detail record (CDR)

A record containing data (such as origination, termination, length, and time of day) unique to a specific call.

candidate configuration

A file maintained by the JUNOS software containing all changes to the router’s active configuration. It becomes the active configuration when a user issues the commit command.

candidate-RP-advertisements

Information sent by routers in a multicast network when they are configured as a local rendezvous point. This information is unicast to the BSR for the multicast domain.

CDMA2000

Radio transmission and backbone technology for the evolution to third-generation (3G) mobile networks.

cell tax

Describes the physical transmission capacity used by header information when sending data packets in an ATM network. Each ATM cell uses a 5-byte header.

CFM

Cubic feet per minute. Measure of air flow in volume per minute.

Challenge Handshake Authentication Protocol (CHAP)

A protocol that authenticates remote users. CHAP is a server-driven, three-step authentication mechanism that depends on a shared secret password that resides on both the server and the client.

channel service unit/data service unit (CSU/DSU)

The channel service unit connects a digital phone line to a multiplexer or other digital signal device. The data service unit connects a DTE to a digital phone line.

chassis daemon (chassisd)

JUNOS software process responsible for managing the interaction of the router’s physical components.

circuit cross-connect (CCC)

A JUNOS software feature that allows you to configure transparent connections between two circuits.

Cisco-RP-Announce

Message advertised into a multicast network by any router configured as a local rendezvous point in an auto-RP network. It is advertised in a dense-mode fashion to the 224.0.1.39 multicast group address.

Cisco-RP-Discovery

Message advertised by the mapping agent in an auto-RP network. It contains the rendezvous point to multicast group address assignments for the domain. It is advertised in a dense-mode fashion to the 224.0.1.40 multicast group address.

class of service (CoS)

The method of classifying traffic on a packet-by-packet basis to provide different service levels to different traffic. See also type of service (ToS).

classless interdomain routing (CIDR)

A method of specifying Internet addresses in which you explicitly specify the bits of the address to represent the network address instead of determining this information from the first octet of the address.

client peer

In a BGP route reflection network, a member of a cluster that is not the route reflector. See also nonclient peer.

cluster

In BGP, a set of routers that have been grouped together. A cluster consists of at least one system that acts as a route reflector, along with any number of client peers. The client peers mainly receive their route information from the route reflector system. Routers in a cluster do not need to be fully meshed.

Code Division Multiple Access (CDMA)

Technology for digital transmission of radio signals between, for example, a mobile telephone and a base transceiver station (BTS).

command completion

Function of the router’s command-line interface that allows a user to enter only the most significant characters in any command. Users access this function through the spacebar or Tab key.

command-line interface (CLI)

The user’s interface to the JUNOS software through a console, Telnet, or SSH session.

common language equipment identifier (CLEI)

Inventory code used to identify and track telecommunications equipment.

community

In BGP, a group of destinations that share a common property. Community information can be included as one of the path attributes in BGP update messages.

Competitive Local Exchange Carrier (CLEC)

(Pronounced “see-lek”) Company that competes with the already established local telecommunications business by providing its own network and switching.

complete sequence number PDU (CSNP)

Packet that contains a complete list of all the LSP headers in the IS-IS database.

confederation

In BGP, a group of small Autonomous Systems that appears to external Autonomous Systems to be a single Autonomous System.

configuration mode

JUNOS software mode allowing a user to alter the router’s current configuration.

Connect

BGP neighbor state where the local router has initiated the TCP session and is waiting for the remote peer to complete the TCP connection.

Connectionless Network Protocol (CLNP)

ISO-developed protocol for OSI connectionless network service. CLNP is the OSI equivalent of IP.

Connector Interface Panel (CIP)

On an M40e or M160 router as well as on a T320 or T640 routing node the panel that contains connectors for the Routing Engines, BITS interfaces, and alarm relay contacts.

constrained path

In traffic engineering, a path determined using the CSPF algorithm. The ERO carried in the RSVP packets contains the constrained path information.

Constrained Shortest Path First (CSPF)

An MPLS algorithm that has been modified to take into account specific restrictions when calculating the shortest path across the network.

context-sensitive help

Function of the router’s command-line interface that allows a user to request information on the JUNOS software command hierarchy. It is accessed in both operational as well as configuration modes.

contributing routes

Active IP routes in the routing table that share the same most significant bits and are more specific than an aggregate or generate route.

Control Board (CB)

On a T640 routing node, part of the host subsystem that provides control and monitoring functions for router components.

core

The central backbone of the network.

craft interface

Mechanisms used by a Communication Workers of America craftsperson to operate, administer, and maintain equipment or provision data communications. On a Juniper Networks router, the craft interface allows you to view status and troubleshooting information and perform system control functions.

customer edge device (CE device)

Router or switch in the customer’s network that is connected to a service provider’s provider edge (PE) router and participates in a Layer 3 or Layer 2 VPN.

customer premises equipment (CPE)

Telephone or other service provider equipment located at a customer site.

Customized Application of Mobile Enhance Logic (CAMEL)

ETSI standard for GSM networks that enhances the provision of Intelligent Network services.