User's Manual

User’s Manual of SGS-5240 Series Managed Switch
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IGMP Querier
A router sends IGMP Query messages onto a particular link. This router is called the Querier.
IMAP
IMAP is an acronym for Internet Message Access Protocol. It is a protocol for email clients to retrieve email messages
from a mail server.
IMAP is the protocol that IMAP clients use to communicate with the servers, and SMTP is the protocol used to
transport mail to an IMAP server.
The current version of the Internet Message Access Protocol is IMAP4. It is similar to Post Office Protocol version
3 (POP3), but offers additional and more complex features. For example, the IMAP4 protocol leaves your email
messages on the server rather than downloading them to your computer. If you wish to remove your messages
from the server, you must use your mail client to generate local folders, copy messages to your local hard drive,
and then delete and expunge the messages from the server.
IP
IP is an acronym for Internet Protocol. It is a protocol used for communicating data across an internet network.
IP is a "best effort" system, which means that no packet of information sent over it is assured to reach its
destination in the same condition it was sent. Each device connected to a Local Area Network (LAN) or Wide Area
Network (WAN) is given an Internet Protocol address, and this IP address is used to identify the device uniquely
among all other devices connected to the extended network.
The current version of the Internet protocol is IPv4, which has 32-bits Internet Protocol addresses allowing for in
excess of four billion unique addresses. This number is reduced drastically by the practice of webmasters taking
addresses in large blocks, the bulk of which remain unused. There is a rather substantial movement to adopt a
new version of the Internet Protocol, IPv6, which would have 128-bits Internet Protocol addresses. This number
can be represented roughly by a three with thirty-nine zeroes after it. However, IPv4 is still the protocol of choice
for most of the Internet.
IPMC
IPMC is an acronym for IP Multicast.
IP Source Guard
IP Source Guard is a secure feature used to restrict IP traffic on DHCP snooping untrusted ports by filtering traffic
based on the DHCP Snooping Table or manually configured IP Source Bindings. It helps prevent IP spoofing
attacks when a host tries to spoof and use the IP address of another host.
L
LACP
LACP is an IEEE 802.3ad standard protocol. The Link Aggregation Control Protocol allows bundling several physical
ports together to form a single logical port.
LLDP
LLDP is an IEEE 802.1ab standard protocol.
The Link Layer Discovery Protocol(LLDP) specified in this standard allows stations attached to an IEEE 802 LAN to
advertise, to other stations attached to the same IEEE 802 LAN, the major capabilities provided by the system
incorporating that station, the management address or addresses of the entity or entities that provide management of
those capabilities, and the identification of the stations point of attachment to the IEEE 802 LAN required by those
management entities. The information distributed via this protocol is stored by its recipients in a standard Management
Information Base (MIB), making it possible for the information to be accessed by a Network Management System
(NMS) using a management protocol such as the Simple Network Management Protocol (SNMP).
LLDP-MED
LLDP-MED is an extension of IEEE 802.1ab and is defined by the telecommunication industry association (TIA-1057).