CCNA Cisco Certified Network Associate Study Guide - FTP Server

Glossary 651
ABM Asynchronous Balanced Mode: When two stations can initiate a
transmission, ABM is an HDLC (or one of its derived protocols) communication
technology that supports peer-oriented, point-to-point communications
between both stations.
ABR Area Border Router: An OSPF router that is located on the border of
one or more OSPF areas. ABRs are used to connect OSPF areas to the OSPF
backbone area.
access layer One of the layers in Cisco’s three-layer hierarchical model.
The access layer provides users with access to the internetwork.
access link Is a link used with switches and is only part of one Virtual
LAN (VLAN). Trunk links carry information from multiple VLANs.
access list A set of test conditions kept by routers that determines “interesting
traffic” to and from the router for various services on the network.
access method The manner in which network devices approach gaining
access to the network itself.
access server Also known as a “network access server,” it is a communications
process connecting asynchronous devices to a LAN or WAN through
network and terminal emulation software, providing synchronous or asynchronous
routing of supported protocols.
acknowledgment Verification sent from one network device to another
signifying that an event has occurred. May be abbreviated as ACK. Contrast
with: NAK.
ACR allowed cell rate: A designation defined by the ATM Forum for managing
ATM traffic. Dynamically controlled using congestion control measures,
the ACR varies between the minimum cell rate (MCR) and the peak
cell rate (PCR). See also: MCR and PCR.
active monitor The mechanism used to manage a Token Ring. The network
node with the highest MAC address on the ring becomes the active
monitor and is responsible for management tasks such as preventing loops
and ensuring tokens are not lost.