User's Manual

T-311 11Mb High Gain Smart Ethernet Client User’s Guide
Gemtek Systems Page 32
G
gateway: A gateway is a network point that
acts as an entrance to another network. On the
Internet, a node or stopping point can be either
a gateway node or a host (end-point) node.
Both the computers of Internet users and the
computers that serve pages to users are host
nodes. The computers that control traffic within
your company's network or at your local
Internet service provider (ISP) are gateway
nodes.
H
hot-spot: A hot-spot is wireless public access
system that allows subscribers to be
connected to a wireless network in order to
access the Internet or other devices, such as
printers. Hot-spots are created by WLAN
access points, installed in public venues.
Common locations for public access are hotels,
airport lounges, railway stations or coffee
shops.
hot-spot operator: An entity that operates a
facility consisting of a Wi-Fi public access
network and participates in the authentication.
HTTP: The Hypertext Transfer Protocol (HTTP)
is the set of rules for exchanging files (text,
graphic images, sound, video, and other
multimedia files) on the World Wide Web.
Relative to the TCP/IP suite of protocols (which
are the basis for information exchange on the
Internet), HTTP is an application protocol.
HTTPS: HTTPS (Hypertext Transfer Protocol
over Secure Socket Layer, or HTTP over SSL)
is a Web protocol developed by Netscape and
built into its browser that encrypts and decrypts
user page requests as well as the pages that
are returned by the Web server. HTTPS is
really just the use of Netscape's Secure Socket
Layer (SSL) as a sublayer under its regular
HTTP application layering.
I
ICMP: ICMP (Internet Control Message
Protocol) is 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.
IEEE: Institute of Electrical and Electronics
Engineers. The IEEE describes itself as the
world's largest professional society. The IEEE
fosters the development of standards that often
become national and international standards,
such as 802.11.
IP: The Internet Protocol (IP) is the method or
protocol by which data is sent from one
computer to another on the Internet. Each
computer (known as a host) on the Internet has
at least one IP address that uniquely identifies
it from all other computers on the Internet.
When you send or receive data (for example,
an e-mail note or a Web page), the message
gets divided into little chunks called packets.
Each of these packets contains both the
sender's Internet address and the receiver's
address. Any packet is sent first to a gateway
computer that understands a small part of the
Internet. The gateway computer reads the
destination address and forwards the packet to
an adjacent gateway that in turn reads the
destination address and so forth across the
Internet until one gateway recognizes the
packet as belonging to a computer within its
immediate neighborhood or domain. That
gateway then forwards the packet directly to
the computer whose address is specified.
IPsec: IPsec (Internet Protocol Security) is a
developing standard 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 will be
especially useful for implementing virtual
private networks and for remote user access
through dial-up connection to private networks.
A big advantage of IPsec is that security
arrangements can be handled without requiring
changes to individual user computers. Cisco
has been a leader in proposing IPsec as a
standard (or combination of standards and
technologies) and has included support for it in
its network routers.
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.
ISP: An ISP (Internet Service Provider) is a
company that provides individuals and other
companies access to the Internet and other