User’s Manual of MGSW-MGSD Series
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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.
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
Q
uality
o
f
S
ervice. 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.