User’s Manual of WGR-500-4P and WGR-500-4PV
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PD is an acronym for
P
owered
D
evice. 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.
POP3
POP3 is an acronym for
P
ost
O
ffice
P
rotocol 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.
PPPoE
PPPoE is an acronym for Point-to-Point Protocol over Ethernet.
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).
Q
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,
