ifs NS3562-8P-2S-V2, Руководство пользователя

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NS3562-8P-2S-V2 Industrial Managed Switch User Manual 349
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 email 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 email and are not to
be confused with the Simple Mail Transfer Protocol (SMTP).
You send email with SMTP, and a mail handler receives it on
the recipient's behalf. Then, the mail is read using POP or
IMAP.
PPPoE Point-to-Point Protocol over Ethernet. It is a network protocol
for encapsulating Point-to-Point Protocol (PPP) frames inside
Ethernet frames (Wikipedia). It is used mainly with ADSL
services where individual users connect to the ADSL
transceiver (modem) over Ethernet and in plain Metro Ethernet
networks.
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 Precision Time Protocol. A network protocol for synchronizing
the clocks of computer systems.
Q
QCE QoS Control Entry. It describes the QoS class associated with
a particular QCE ID.
There are six QCE frame types: Ethernet Type, VLAN,
UDP/TCP Port, DSCP, TOS, and Tag Priority. Frames can be
classified by one of four different QoS classes: "Low",
"Normal," "Medium," and "High" for individual application.