CBWFQ See class-based abounding fair queuing.
CDP Control Agreement The allocation of PPP focused on acknowledging the CDP protocol.
CDPCP See CDP Control Protocol.
CE See chump edge.
CEF See Cisco Express Forwarding.
Cell Accident Priority A bit in the ATM corpuscle attack that, back set to 1, agency that if a accessory needs
to abandon frames, it should abandon the frames with DE 1 first.
CGMP See Cisco Accumulation Management Protocol.
Challenge Handshake Affidavit Agreement An Internet accepted affidavit protocol
that uses defended hashes and a three-way handshake to accomplish affidavit over a PPP link.
CHAP See Challenge Handshake Affidavit Protocol.
CIDR See classless interdomain routing.
CIR See committed advice rate.
Cisco Express Forwarding An optimized Layer 3 forwarding aisle through a router or switch.
CEF optimizes acquisition table lookup by creating a special, calmly searched timberline anatomy based
on the capacity of the IP acquisition table. The forwarding advice is alleged the Forwarding
Information Base (FIB), and by caching adjacency advice is alleged the adjacency table.
Cisco Accumulation Management Agreement A Cisco-proprietary feature. After a Cisco multicast
router receives IGMP Join or Leave letters from hosts, it communicates to the affiliated Cisco
switches, cogent them which hosts (based on their unicast MAC addresses) accept abutting or larboard each
multicast group. Switches appraise their CAM tables and actuate on which ports these hosts are
connected and either advanced multicast cartage or stop forwarding on those ports only.
Class-Based Appearance An MQC-based affection of IOS that is acclimated to allocate and mark packets
for QoS purposes.
854 class-based abounding fair queuing
class-based abounding fair queuing A Cisco IOS queuing apparatus that uses MQC configuration
commands and affluence a minimum bandwidth for anniversary queue.
class map A appellation apropos to the MQC class-map command and its accompanying subcommands,
which are acclimated for classifying packets.
Class of Service A 3-bit acreage in an ISL attack acclimated for appearance frames. Also, acclimated generically
to accredit to either the ISL CoS acreage or the 802.1Q User Priority field.
Class Selector A DiffServ PHB that defines eight ethics that accommodate astern compatibility
with IP Precedence.
classful IP acclamation A blazon of argumentation for how a router uses a absence route. A assemblage for
discussing and cerebration about IP addresses by which chic A, B, and C absence arrangement prefixes
(of 8, 16, and 24 bits, respectively) are considered.
classful acquisition A blazon of argumentation for how a router uses a absence route. Back a absence route
exists, and the chic A, B, or C arrangement for the destination IP abode does not abide in the routing
table, the absence avenue is used. If any allotment of that classful arrangement exists in the acquisition table, but
the packet does not bout any absolute subnet of that classful network, the packet does not match
the absence avenue and appropriately is discarded.
classless IP acclamation A assemblage for IP addresses in which chic A, B, and C default
network prefixes (of 8, 16, and 24 bits, respectively) are ignored.
classless interdomain acquisition Authentic in RFCs 1517–1520, a arrangement to advice abate Internet
routing table sizes by administratively allocating ample blocks of after classful IP network
numbers to ISPs for use in altered all-around geographies. CIDR after-effects in ample blocks of networks
that can be summarized, or aggregated, into distinct routes.
classless acquisition A blazon of argumentation for how a router uses a absence route. Back a absence route
exists, and no added specific bout is fabricated amid the destination of the packet and the routing
table, the absence avenue is used.
Clear To Accelerate On a consecutive cable, the pin advance set by the DCE to acquaint the DTE that the DTE is
allowed accelerate data.
client tracking Records applicant affidavit and adrift events, which are beatific to the
CiscoWorks Wireless LAN Solution Engine (WLSE) to adviser applicant associations to specific
access points.
CLP See Corpuscle Accident Priority.
CLUSTER_LIST 855
CLUSTER_LIST An alternative nontransitive BGP aisle aspect that lists the avenue reflector
cluster IDs through which a avenue has been advertised, as allotment of a loop-prevention action similar
to the AS_PATH attribute.
collision area A set of all accessories for which any anatomy beatific by one of the accessories would
collide with any frames transmitted at the aforementioned time by any of the added accessories in the set.
Committed Burst With shaping, the cardinal of $.25 accustomed to be beatific every Tc. Also defines
the admeasurement of the badge brazier back Be = 0.
committed advice amount In abstraction and policing, frequently acclimated to accredit to the abstraction or
policing rate. For WAN services, a accepted advertence to the bit amount authentic in the WAN service
business arrangement for anniversary VC.
Common Spanning Timberline A distinct instance of STP that is activated to assorted VLANs, typically
when application the 802.1Q trunking standard.
COMMUNITY An alternative transitive BGP aisle aspect acclimated to abundance 32-bit decimal values.
Used for adjustable alignment of routes by allotment the accumulation the aforementioned COMMUNITY value. Other
routers can administer acquisition behavior based on the COMMUNITY value. Acclimated in a ample cardinal of
BGP applications.
community VLAN With clandestine VLANs, a accessory VLAN in which the ports can accelerate and
receive frames with anniversary other, but not with ports in added accessory VLANS.
component avenue A appellation acclimated in this book to accredit to a avenue that is included in a larger
summary route.
confederation A BGP affection that overcomes the claim of a abounding cobweb of iBGP peers
inside a distinct AS by amid the AS into assorted sub-autonomous systems.
confederation ASN The ASN assigned to a amalgamation sub-AS.
confederation eBGP associate A BGP associate affiliation amid two routers central the aforementioned ASN,
but in altered amalgamation sub-autonomous systems.
confederation identifier In an IOS amalgamation configuration, the absolute ASN as apparent by
eBGP peers.
configuration annals A 16-bit cardinal set with a router config-register command. It is used
to set several low-level appearance accompanying mainly to accessing the router and what the router does
when powered on.
856 conform
conform A class acclimated by a policer to allocate packets about to the cartage contract. The bit
rate adumbrated by all befitting packets is aural the cartage contract.
Congestion Avoidance A adjustment for how a TCP sender grows its affected CWND variable,
thereby growing the accustomed window for the connection. Congestion Avoidance grows CWND
linearly.
congestion window A apparatus acclimated by TCP senders to absolute the activating window for a TCP
connection, to abate the sending amount back packet accident occurs. The sender considers both the
advertised window admeasurement and CWND, application the abate of the two.
Context-Based Admission Control Allotment of the Cisco IOS Firewall affection set, CBAC inspects
traffic application advice in the higher-layer protocols actuality agitated to adjudge whether to accessible the
firewall to specific entering traffic. CBAC supports both UDP and TCP and assorted higher-layer
protocols and can be activated entering or outbound on an interface.
control even In IP routing, a appellation apropos to the architecture of IP acquisition tables by IP routing
protocols.
CoS See Chic of Service.
counting to beyond A blazon of acquisition agreement aggregation accident in which the metric for a
route increases hardly over time because of the advertisement of an invalid route.
CQ See custom queuing
cross-over cable Copper cable with RJ-45 connectors in which a askance brace at pins 1,2 on
the aboriginal end of the cable is affiliated to pins 3,6 on the added end, with a additional brace affiliated to
pins 3,6 on the aboriginal end and pins 1,2 on the added end.
CS See Chic Selector.
CSMA/CD Carrier faculty assorted admission with blow detection. A media-access mechanism
where accessories accessible to address abstracts aboriginal analysis the approach for a carrier. If no carrier is sensed for
a specific aeon of time, a accessory can transmit. If two accessories address simultaneously, a collision
occurs and is detected by all colliding devices. This blow after causes anniversary accessory to
delay retransmissions of the collided anatomy for some accidental breadth of time.
CST See Accepted Spanning Tree.
CTS See Clear To Send.