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Optional TLVs
OUI
P
PCP
PD
PHY
PING
PoE
Policer
Private VLAN
A LLDP frame contains multiple TLVs. For some TLVs, it is configurable if the switch
shall include the TLV in the LLDP frame. These TLVs are known as optional TLVs. If an
optional TLVs is disabled, the corresponding information is not included in the LLDP
frame.
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.
PCP is an acronym for Priority Code Point. It is a 3-bit field storing the priority level
for the 802.1Q frame. It is also known as User Priority.
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 is an abbreviation for Physical Interface Transceiver and is the device that
implements the Ethernet physical layer (IEEE-802.3).
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 is an acronym for Power over Ethernet. Power over Ethernet is used to transmit
electrical power to remote devices over standard Ethernet cable. 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.
A policer can limit the bandwidth of received frames. It is located in front of the
ingress queue.
In a private VLAN, communication between ports in that private VLAN is not
permitted. A VLAN can be configured as a private VLAN.