GL-1
Cisco CRS-1 Series Carrier Routing System Getting Started Guide
GLOSSARY
A
AAA
authentication, authorization, and accounting. A network security service that provides the primary
framework to set up access control on a Cisco CRS-1 router or access server. AAA is an architectural
framework and modular means of configuring three independent, but closely related security functions
in a consistent manner.
ACK
acknowledged. Notification sent from one network device to another to acknowledge that some event
occurred (for example, the receipt of a message).
ACL
access control list. A list kept by routers to control access to or from the router for a number of services
(for example, to prevent packets with a certain IP address from leaving a particular interface on the
router).
ACK
acknowledged. Notification sent from one network device to another to acknowledge that some event
occurred (for example, the receipt of a message).
active
Denotes a card or process that performs a system task; in a redundant configuration, there is an inactive
standby card or process available to become active. Active cards or processes are also sometimes
denoted as primary.
active RP
The RP that is active in a redundant pair of RPs. The primary RP in slot 0 is set as the active RP at
system bootup.
active software
configuration
The software configuration marked as active for a node.
active software set
The set of Cisco IOS XR software packages activated in one or more nodes in a Cisco CRS-1 Series
router.
adSCp
auxiliary designated shelf controller process. The dSCp running on all the non-dSC nodes.
affinity
Requirements of an MPLS traffic engineering tunnel on the attributes of the links it will cross. The
tunnel's affinity bits and affinity mask bits of the tunnel must match the attribute bits of the various links
carrying the tunnel. See also MPLS.
algorithm
A well-defined rule or process for arriving at a solution to a problem. In networking, algorithms
commonly are used to determine the best route for traffic from a particular source to a particular
destination.
APS
automatic protection switching. A method that allows transmission equipment to recover automatically
from failures, such as a cut cable.
ASIC
application-specific integrated circuit. A chip designed for use in a specific hardware device. An ASIC
is a chip designed for a special application, such as a particular kind of transmission protocol.