User`s guide

NETWORK IP CAMERA User’s Guide
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J. Glossary of Terms
ActiveX – A control (or set of rules) used by a browser. ActiveX controls are often downloaded and
installed automatically as required.
ARP – Address Resolution Protocol. A method for finding a host's Ethernet address from its Internet
address. The sender broadcasts an ARP packet containing the Internet address of another host and
waits for it (or some other host) to send back its Ethernet address. Each host maintains a cache of
address translations to reduce delay and loading. ARP allows the Internet address to be independent of
the Ethernet address but it only works if all hosts support it. The ARP command can be used to set the
IP – addresses for your product.
CGI – A standard for running external programs from a World-Wide Web HTTP server. CGI specifies
how to pass arguments to the executing program as part of the HTTP request. It also defines a set of
environment variables. Commonly, the program will generate some HTML which will be passed back
to the browser but it can also request URL redirection. A set of rules (or a program) that allows a Web
Server to communications with other programs.
DSL – Digital Subscriber Loop, A family of digital telecommunications protocols designed to allow
high speed data communication over the existing copper telephone lines between end-users and
telephone companies.
DHCP - A protocol that provides a means to dynamically allocate IP addresses to computers on a
local area network. The system administrator assigns a range of IP addresses to DHCP and each client
computer on the LAN has its TCP/IP software configured to request an IP address from the DHCP
server. The request and grant process uses a lease concept with a controllable time period.
Ethernet –A widely used networking standard.
Firewall –A virtual barrier between a LAN (Local Area Network) and other networks, e.g. the Internet.
Frame Grabber Card – Plug-in hardware for “grabbing” images.
FTP - A client-server protocol that allows a user on one computer to transfer files to and from another
computer over a TCP/IP network. Also the client program the user executes to transfer files. It is