CTC Union FRM220-MX210 series, User Manual

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APPENDIX A
ACRONYMS
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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, 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.
PTP
PTP is an acronym for Precision Time Protocol, a network protocol for synchronizing the clocks of computer systems.
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.
QCI
QCI is an acronym for QoS Class Identifier. This is a special identifier defining the quality of packet communication
provided by LTE (Long Term Evolution, marketed as 4G LTE).
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.
A communications network transports a multitude of applications and data, including high-quality video and delay-
sensitive data such as real-time voice. Networks must provide secure, predictable, measurable, and sometimes
guaranteed services.
Achieving the required QoS becomes the secret to a successful end-to-end business solution. Therefore, QoS is the
set of techniques to manage network resources.
QoS class
Every incoming frame is classified to a QoS class, which is used throughout the device for providing queuing,
scheduling and congestion control guarantees to the frame according to what was configured for that specific QoS
class. There is a one to one mapping between QoS class, queue and priority. A QoS class of 0 (zero) has the lowest
priority.