OAM
Operation Administration & Maintenance is a protocol described in ITU-T Y.1731. It is used to implement
carrier ethernet functionality.
OSPF
An interior gateway routing protocol for TCP/IP networks, Open Shortest Path First uses a link state
routing algorithm that calculates routes for packets based on a number of factors, including least hops,
speed of transmission lines, and congestion delays. You can also configure certain cost metrics for the
algorithm. This protocol is more efficient and scalable than vector-distance routing protocols. OSPF
features include least-cost routing,
routing, and load balancing. Although
OSPF requires CPU power and memory space, it results in smaller, less frequent router table updates
throughout the network. This protocol is more efficient and scalable than vector-distance routing
protocols.
PCP
The Priority Code Point is a 3-bit field that stores the priority-level for the 802.1Q frame. It is also known
as User Priority.
PDU
A Protocol Data Unit is a message of a given protocol comprising payload and protocol-specific control
information, typically contained in a header.
PEAP
Protected Extensible Authentication Protocol is an
IETF (Internet Engineering Task Force)
draft standard
to authenticate wireless LAN clients without requiring them to have certificates. In PEAP authentication,
first the user authenticates the authentication server, then the authentication server authenticates the
user. If the first phase is successful, the user is then authenticated over the SSL tunnel created in phase
one using EAP-Generic Token Card (EAP-GTC) or Microsoft Challenged Handshake Protocol Version 2
(MSCHAP V2). (See also
PHY
The Physical Interface Transceiver is the device that implements the Ethernet physical layer
(IEEE-802.3).
PoE
The Power over Ethernet standard (IEEE 802.3af) defines how power can be provided to network
devices over existing Ethernet connections, eliminating the need for additional external power supplies.
PVST+
Per VLAN Spanning Tree +. This implementation of
has a 1:1 relationship
with VLANs. The Extreme Networks implementation of PVST+ allows you to interoperate with third-
party devices running this version of STP. PVST is a earlier version of this protocol and is compatible
with PVST+.
QL
QL In SyncE this is the Quality Level of a given clock source. This is received on a port in a SSM
indicating the quality of the clock received in the port.
QoS
Glossary
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