Extreme Networks ExtremeWare XOS 11.3, Manual

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ExtremeWare XOS 11.3 Concepts Guide
645
Glossary
A
AAA Authentication, authorization, and accounting. A system to control
which computer resources specific users can access and to keep track
of the activity of specific users over the network.
ABR Area border router. In OSPF, an ABR has interfaces in multiple areas,
and it is responsible for exchanging summary advertisements with
other ABRs.
ACL Access Control List. ACLs are a mechanism for filtering packets at the
hardware level. Packets can be classified by characteristics such as the
source or destination MAC, IP addresses, IP type, or QoS queue. Once
classified, the packets can be forwarded, counted, queued, or dropped.
In Extreme Networks XOS software, you configure ACLs by creating a
file, called a policy file (with a .
pol file extension). The system parses
the policy file and loads the ACL into the hardware.
alternate port In RSTP, the alternate port supplies an alternate path to the root
bridge and the root port.
AP Access point. In wireless technology, access points are the devices that
connect to the regular wired network and forward and receive the
radio signals that transmit wireless data.
area In OSPF, an area is a logical set of segments connected by routers. The
topology within an area is hidden from the rest of the AS.
ARP Address Resolution Protocol. ARP is part of the TCP/IP suite used to
dynamically associate a device’s physical address (MAC address) with
its logical address (IP address). The system broadcasts an ARP
request, containing the IP address, and the device with that IP address
sends back its MAC address so that traffic can be transmitted.
AS Autonomoous system. In OSPF, an AS is a connected segment of a
network topology that consists of a collection of subnetworks (with
hosts attached) interconnected by a set of routes. The subnetworks and
the routers are expected to be under the control of a single
administration. Within an AS, routers may use one or more interior
routing protocols and sometimes several sets of metrics. An AS is
expected to present to other ASs an appearance of a coherent interior
routing plan and a consistent picture of the destinations reachable
through the AS. An AS is identified by a unique 16-bit number.
ASBR Autonomous system border router. In OSPF, an ASBR acts as a
gateway between OSPF and other routing protocols or other ASs.