Interlogix NS3550-2T-8S User Manual User Manual
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IFS NS3552-8P-2S AND NS3550-2T-8S User Manual
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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. 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.
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.
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).
Private VLAN
In a private VLAN, PVLANs provide layer 2 isolation between ports within the same broadcast domain. Isolated ports