User's Manual

User’s Manual of SGS-5240 Series Managed Switch
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NFS
NFS is an acronym for Network File System. It allows hosts to mount partitions on a remote system and use them as
though they are local file systems.
NFS allows the system administrator to store resources in a central location on the network, providing authorized
users continuous access to them, which means NFS supports sharing of files, printers, and other resources as
persistent storage over a computer network.
NTP
NTP is an acronym for Network Time Protocol, a network protocol for synchronizing the clocks of computer
systems. NTP uses UDP (datagrams) as transport layer.
O
OAM
OAM is an acronym for Operation Administration and Maintenance. It is a protocol described in ITU-T Y.1731 used
to implement carrier Ethernet functionality. MEP functionality like CC and RDI is based on this.
Optional TLVs.
An LLDP frame contains multiple TLVs. For some TLVs it is configurable if the switch includes the TLV in the LLDP
frame. These TLVs are known as optional TLVs. If an optional TLV is disabled the corresponding information is not
included in the LLDP frame.
OUI
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 an 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.