User manual

User Manual
Publication date: Feb., 2013
Revision A3
272
Power over Ethernet is used to transmit electrical power, to remote devices over standard
Ethernet cable. It could for example be used for powering IP telephones, wireless LAN access
points and other equipment, where it would be difficult or expensive to connect the equipment
to main power supply.
Policer
A policer can limit the bandwidth of received frames. It is located in front of the ingress queue.
POP3
POP3 is an acronym for Post Office Protocol version 3. It is a protocol for email clients to
retrieve email messages from a mail server.
POP3 is designed to delete mail on the server as soon as the user has downloaded it.
However, some implementations allow users or an administrator to specify that mail be saved
for some period of time. POP can be thought of as a "store-and-forward" service.
An alternative protocol is Internet Message Access Protocol (IMAP). IMAP provides the user
with more capabilities for retaining e-mail on the server and for organizing it in folders on the
server. IMAP can be thought of as a remote file server.
POP and IMAP deal with the receiving of e-mail and are not to be confused with the Simple
Mail Transfer Protocol (SMTP). You send e-mail with SMTP, and a mail handler receives it on
your recipient's behalf. Then the mail is read using POP or IMAP. IMAP4 and POP3 are the
two most prevalent Internet standard protocols for e-mail retrieval. Virtually all modern e-mail
clients and servers support both.
Private VLAN
In a private VLAN, communication between ports in that private VLAN is not permitted. A
VLAN can be configured as a private VLAN.
PTP
PTP is an acronym for Precision Time Protocol, a network protocol for synchronizing the
clocks of computer systems.
Q
QCE
QCE is an acronym for QoS Control Entry. It describes QoS class associated with a particular
QCE ID.
There are six QCE frame types: Ethernet Type, VLAN, UDP/TCP Port, DSCP, TOS, and Tag
Priority. Frames can be classified by one of 4 different QoS classes: "Low", "Normal",
"Medium", and "High" for individual application.
QCL
QCL is an acronym for QoS Control List. It is the list table of QCEs, containing QoS control
entries that classify to a specific QoS class on specific traffic objects.
Each accessible traffic object contains an identifier to its QCL. The privileges determine
specific traffic object to specific QoS class.
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
QoS is an acronym for Quality of Service. It is a method to guarantee a bandwidth
relationship between individual applications or protocols.