User`s guide

Glossary
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File Transfer Protocol (FTP)
A standard Internet protocol that specifies the simplest way to exchange files between computers
on the Internet.
HyperText Transfer Protocol (HTTP)
An application protocol in the TCP/IP suite that defines the rules for transferring files (text,
graphic images, sound, video, and other multimedia files) on the World Wide web (WWW).
HyperText Transfer Protocol over Secure Socket Layer (HTTPS)
A secure message-oriented communications protocol designed for use in conjunction with
HTTP. HTTPS encrypts and decrypts user page requests as well as the pages that are returned
by the web server. HTTPS uses the Secure Socket Layer (SSL) as a sublayer.
Internet Control Message Protocol (ICMP)
A message control and error-reporting protocol between a host server and a gateway to the
Internet. ICMP uses Internet Protocol (IP) datagrams, but the messages are processed by the IP
software and are not directly apparent to the application user.
Internet Group Management Protocol (IGMP)
Internet Group Management Protocol (IGMP) provides a way for an Internet computer to report
its multicast group membership to adjacent routers. Multicasting allows one computer on the
Internet to send content to multiple other computers that have identified themselves as interested
in receiving the originating computer's content. Multicasting can be used for such applications
as updating the address books of mobile computer users in the field, sending out company
newsletters to a distribution list, and “broadcasting” high-bandwidth programs of streaming
media to an audience that has “tuned in” by setting up a multicast group membership.
IP filtering
A network configuration that can be enabled to establish rules allowing devices to permit or deny
specific IP addresses, networks, or devices from connection access. Also known as access
control list.
IPsec (Internet Protocol Security)
A framework for a set of protocols for security at the network or packet processing layer of
network communication. Earlier security approaches have inserted security at the application
layer of the communications model. IPsec is said to be especially useful for implementing virtual
private networks and for remote user access through dial-up connection to private networks. An
advantage of IPsec is that security arrangements can be handled without requiring changes to
individual user computers.
IPsec provides two choices of security service: Authentication Header (AH), which essentially
allows authentication of the sender of data, and Encapsulating Security Payload (ESP), which
supports both authentication of the sender and encryption of data as well. The specific
information associated with each of these services is inserted into the packet in a header that
follows the IP packet header. Separate key protocols can be selected, such as the ISAKMP/
Oakley protocol.