ZyXEL Communications XGS3600 Series Manual page 340

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
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
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 and is the device that
implement 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.
Policer
A policer can limit the bandwidth of received frames. It is located in front of the ingress
queue.
POP3
POP3 is an acronym for Post Office Protocol version 3. It is a protocol for email clients to
retrieve email messages from a mail server.
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.
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.
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