User Manual
Appendix E: Glossary
Gateway
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Psion Teklogix 9160 Wireless Gateway User Manual
source and destination MAC address, a control field with protocol version, frame
type, frame sequence number, frame body (with the actual information to be
transmitted) and frame check sequence for error detection. A Frame is similar in
concept to a Packet, the difference being that a packet operates on the Network
layer (layer 3 in the OSI model) whereas a frame operates on the Data-Link layer
(layer 2 in the OSI model).
G
Gateway
A gateway is a network node that serves as an entrance to another network. A
gateway also often provides a proxy server and a firewall. It is associated with both
a router, which use headers and forwarding tables to determine where packets are
sent, and a switch or bridge, which provides the actual path for the packet in and out
of the gateway.
Before a host on a LAN can access the Internet, it needs to know the address of its
default gateway.
H
HTML
The Hypertext Markup Language (HTML) defines the structure of a document on
the World Wide Web. It uses tags and attributes to hint about a layout for the
document.
An HTML document starts with an
<html>
tag and ends with a
</html>
tag. A
properly formatted document also contains a
<head>
...
</head>
section, which
contains the metadata to define the document, and a
<body>
...
</body>
section, which
contains its content. Its markup is derived from the Standard Generalized Markup
Language (SGML), which is defined in ISO 8879:1986.
HTML documents are sent from server to browser via HTTP. Also see XML.