ZyXEL Communications XGS3600 Series Manual page 336

IEEE 802.1X
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 Internet Group Management Protocol. 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 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 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.
XGS3600 Series User's Guide
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