PLANET SGSW-24040 - Manual (Page 556)

User’s Manual of SGSW-24040 / 24240 Series
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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.
PPPoE
PPPoE is an acronym for Point-to-Point Protocol over Ethernet.
It is a network protocol for encapsulating Point-to-Point Protocol (PPP) frames inside Ethernet frames. It is used mainly
with ADSL services where individual users connect to the ADSL transceiver (modem) over Ethernet and in plain Metro
Ethernet networks (Wikipedia).
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.