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Glossary
access method
The manner in which network devices approach gaining
access to the network itself.
access rate
Defines the bandwidth rate of the circuit. For example, the
access rate of a T-1 circuit is 1.544Mbps. In Frame Relay and other technol-
ogies, there may be a fractional T-1 connection--256Kbps, for example--
however, the access rate and clock rate is still 1.544Mbps.
access server
Also known as a "network access server," it is a communi-
cations process connecting asynchronous devices to a LAN or WAN through
network and terminal emulation software, providing synchronous or asyn-
chronous routing of supported protocols.
accounting
One of the three components in AAA. Accounting provides
auditing and logging functionalities to the security model.
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 man-
aging ATM traffic. Dynamically controlled using congestion control mea-
sures, 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 net-
work 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.
address learning
Used with transparent bridges to learn the hardware
addresses of all devices on an internetwork. The switch then filters the net-
work with the known hardware (MAC) addresses.
address mapping
By translating network addresses from one format to
another, this methodology permits different protocols to operate inter-
changeably.
address mask
A bit combination descriptor identifying which portion of
an address refers to the network or subnet and which part refers to the host.
Sometimes simply called the mask.
See also: subnet mask.
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