Appendix C:
Glossary
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E
EEE
EEE is an abbreviation for Energy Efficient Ethernet defined in IEEE 802.3az.
EPS
EPS is an abbreviation for Ethernet Protection Switching defined in ITU/T G.8031.
Ethernet Type
Ethernet Type, or EtherType, is a field in the Ethernet MAC header, defined by the Ethernet
networking standard. It is used to indicate which protocol is being transported in an Ethernet
frame.
F
Fast Leave
Multicast snooping Fast Leave processing allows the switch to remove an interface from the
forwarding-table entry without first sending out group specific queries to the interface. The
VLAN interface is pruned from the multicast tree for the multicast group specified in the
original leave message. Fast-leave processing ensures optimal bandwidth management for
all hosts on a switched network, even when multiple multicast groups are in use
simultaneously. This processing applies to IGMP and MLD.
H
HTTP
HTTP is an acronym for
H
ypertext
T
ransfer
P
rotocol. It is a protocol that used to transfer or
convey information on the World Wide Web (WWW).
HTTP defines how messages are formatted and transmitted, and what actions Web servers
and browsers should take in response to various commands. For example, when you enter a
URL in your browser, this actually sends an HTTP command to the Web server directing it to
fetch and transmit the requested Web page. The other main standard that controls how the
World Wide Web works is HTML, which covers how Web pages are formatted and displayed.
Any Web server machine contains, in addition to the Web page files it can serve, an HTTP
daemon, a program that is designed to wait for HTTP requests and handle them when they
arrive. The Web browser is an HTTP client, sending requests to server machines. An HTTP
client initiates a request by establishing a Transmission Control Protocol (TCP) connection to
a particular port on a remote host (port 80 by default). An HTTP server listening on that port
waits for the client to send a request message.
