IFS NS3502-8P-2S User Manual
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IEEE 802.1X is an IEEE standard for port-based Network Access Control. It provides
authentication to devices attached to a LAN port, establishing a point-to-point connection or
preventing access from that port if authentication fails. With 802.1X, access to all switch ports
can be centrally controlled from a server, which means that authorized users can use the same
credentials for authentication from any point within the network.
IGMP
IGMP is an acronym for
I
nternet
G
roup
M
anagement
P
rotocol. It is a communications protocol
used to manage the membership of Internet Protocol multicast groups. IGMP is used by IP hosts
and adjacent multicast routers to establish multicast group memberships. It is an integral part
of the IP multicast specification, like ICMP for unicast connections. IGMP can be used for online
video and gaming, and allows more efficient use of resources when supporting these uses.
IGMP Querier
A router sends IGMP Query messages onto a particular link. This router is called the Querier.
IMAP
IMAP is an acronym for
I
nternet
M
essage
A
ccess
P
rotocol. 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
I
nternet
P
rotocol. It is a protocol used for communicating data across a
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
