Appendix C:
Glossary
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PING
Ping is a program that sends a series of packets over a network or the Internet to a specific
computer in order to generate a response from that computer. The other computer responds
with an acknowledgment that it received the packets. Ping was created to verify whether a
specific computer on a network or the Internet exists and is connected.
Ping uses Internet Control Message Protocol (ICMP) packets. The PING Request is the
packet from the origin computer, and the PING Reply is the packet response from the target.
PoE
PoE is an acronym for
P
ower
O
ver
E
thernet.
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.
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
P
recision
T
ime
P
rotocol, a network protocol for synchronizing the
clocks of computer systems.
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.