3Com 3CRDSF9PWR manual Ieee 802.3u, Igmp Snooping, Igmp Query, Internet Control, Message Protocol

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	depending on the capabilities of the attached device. Up to 30 Watts
	can be delivered through each port when using all four pairs.
IEEE 802.3u	Defines CSMA/CD access method and physical layer specifications for
	100BASE-TX and 100BASE-FX Fast Ethernet. (Now incorporated in IEEE
	802.3-2005.)
IEEE 802.3x	Defines Ethernet frame start/stop requests and timers used for flow
	control on full-duplex links. (Now incorporated in IEEE 802.3-2005)
IGMP Snooping	Listening to IGMP Query and IGMP Report packets transferred between
	IP Multicast Routers and IP Multicast host groups to identify IP Multicast
	group members.
IGMP Query	On each subnetwork, one IGMP-capable device can act as the
	querier — that is, the device that asks all hosts to report on the IP
	multicast groups they wish to join or to which they already belong. The
	elected querier is the device with the lowest IP address in the
	subnetwork.
Internet Control	A network layer protocol that reports errors in processing IP packets.
Message Protocol	ICMP is also used by routers to feed back information about better
(ICMP)	routing choices.
Internet Group	A protocol through which hosts can register with their local router for
Management	multicast services. If there is more than one multicast switch/router on a
Protocol (IGMP)	given subnetwork, one of the devices is made the “querier” and
	assumes responsibility for keeping track of group membership.
In-Band Management	Management of the network from a station attached directly to the
	network.
IP Multicast Filtering	A process whereby this switch can pass multicast traffic along to
	participating hosts.
IP Precedence	The Type of Service (ToS) octet in the IPv4 header includes three
	precedence bits defining eight different priority levels ranging from
	highest priority for network control packets to lowest priority for
	routine traffic. The eight values are mapped one-to-one to the Class of
	Service categories by default, but may be configured differently to suit
	the requirements for specific network applications.