Appendix C:
Glossary
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HTTPS
HTTPS is an acronym for
H
ypertext
T
ransfer
P
rotocol over
S
ecure Socket Layer. It is used to
indicate a secure HTTP connection.
HTTPS provide authentication and encrypted communication and is widely used on the World
Wide Web for security-sensitive communication such as payment transactions and corporate
logons.
HTTPS is really just the use of Netscape's Secure Socket Layer (SSL) as a sublayer under its
regular HTTP application layering. (HTTPS uses port 443 instead of HTTP port 80 in its
interactions with the lower layer, TCP/IP.) SSL uses a 40-bit key size for the RC4 stream
encryption algorithm, which is considered an adequate degree of encryption for commercial
exchange.
I
ICMP
ICMP is an acronym for
I
nternet
C
ontrol
M
essage
P
rotocol. It is a protocol that generated the
error response, diagnostic or routing purposes. ICMP messages generally contain
information about routing difficulties or simple exchanges such as time-stamp or echo
transactions. For example, the PING command uses ICMP to test an Internet connection.
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
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.