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Optional TLVs:
A LLDP frame contains multiple TLVs. For some TLVs, it is
configurable if the switch includes the TLV in the LLDP frame. These TLVs are
known as optional TLVs. If an optional TLV is disabled, the corresponding
information is not included in the LLDP frame.
OUI:
OUI is the organizationally unique identifier. An OUI address is a globally unique
identifier assigned to a vendor by IEEE. You can determine which vendor a
device belongs to according to the OUI address, which forms the first 24 bits
of a MAC address.
P
PCP is an acronym for Priority Code Point. It is a 3
-
bit field that stores the
priority level for the 802.1Q frame. It is also known as “User Priority”.
PD:
PD is an acronym for Powered Device. In a PoE system, the power is delivered
from a PSE (power sourcing equipment) to a remote device. The remote
device is called a PD.
PHY:
PHY is an abbreviation for Physical Interface Transceiver. It is the device that
implements the Ethernet physical layer (IEEE
-
802.3).
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 Power Over Ethernet.
Power Over Ethernet is used to transmit electrical power to remote devices
over standard Ethernet cable. For example, it could 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, 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.
