C

CIDR. classless interdomain routing.

Forwarding packets based on their prefix length and destination, ignoring the major network in which they reside.

CIDR block.

Grouping or summarization of major networks. Given that 200.200.200.0/24 is a Class C address, 200.200.0.0/16 is a CIDR block. The address 10.1.0.0/16 is not a CIDR block; it is a subnet of the 10.x.x.x network. With a CIDR block, the prefix is shortened from the "natural" mask for that network; with subnetting, the prefix is lengthened.

classless interdomain routing.

See [CIDR. classless interdomain routing. Forwarding packets based on their prefix length and destination, ignoring the major network in which they reside.]

CLNS. Connectionless Network Service.

A routed (data carrying) protocol; routing information for CLNS is provided by IS-IS.

collapsed core.

A single router (or switch) acting as the core of a network.

common services.

Services internal to an organization that are used by all or most of the end users of the network.

conditional advertisement.

The capability of a routing protocol to advertise a given destination under only certain conditions, such as the existence of another path to that destination.

confederation.

A group of BGP autonomous systems that appear as one AS outside of the confederation.

control component.

A device that assigns labels in an MPLS network.

control-driven label assignment.

Assigning labels based on control traffic, such as routing updates.

convergence.

The process of all the routers in a network determining the best path to reach the destinations available; when the network has converged, all the routers in the network have decided on the best path to each destination.

core.

The area of the network that concentrates on switching traffic.