422
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
P
oint-to-
P
oint
P
rotocol
o
ver
E
thernet.
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, PVLANs provide layer 2 isolation between ports within the same broadcast domain. Isolated ports
configured as part of PVLAN cannot communicate with each other. Member ports of a PVLAN can communicate with
each other.
Q
QCE
QCE is an acronym for
Q
oS
C
ontrol
E
ntry. 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.
Summary of Contents for NS4750-24S-4T-4X
Page 1: ...NS4750 24S 4T 4X User Manual P N 1702826 REV 00 01 ISS 14JUL14 ...
Page 56: ...56 Figure 4 2 7 Privilege Levels Configuration Page Screenshot ...
Page 110: ...110 Figure 4 4 6 Mirror Configuration Page Screenshot ...
Page 117: ...117 Figure 4 5 4 LACP Port Configuration Page Screenshot ...
Page 174: ...174 Figure 4 7 10 MST1 MSTI Port Configuration Page Screenshot ...
Page 180: ...180 Figure 4 8 2 Multicast Flooding ...
Page 249: ...249 Figure 4 9 18 Voice VLAN Configuration Page Screenshot ...
Page 271: ...271 Counter Counts the number of frames that match this ACE ...
Page 281: ...281 Figure 4 11 4 Network Access Server Configuration Page Screenshot ...
Page 315: ...315 ...
Page 328: ...328 ...
Page 335: ...335 ...
Page 346: ...346 Figure 4 14 1 LLDP Configuration Page Screenshot ...
Page 350: ...350 Figure 4 14 2 LLDP MED Configuration Page Screenshot ...
Page 372: ...372 Figure 4 16 1 Loop Protection Configuration Page Screenshot ...