AXIS 2120 User’s Manual High-Speed Services 67
Appendix E - High-Speed Services
You will experience the full performance of the AXIS 2120 if you have access to
high-speed Internet services such as, xDSL or a cable-modem connection. However, as
most high-speed Internet services only provide you with one external IP address, there are
several practical issues that should be considered when developing your application.

Available IP Addresses

Ideally, your ISP (Internet Service Provider) will provide you with several external static IP
addresses - in which case you can assign any one of these to your AXIS 2120 to make it
fully accessible over the internet. However, if your service provider s u pp lies you wi th on ly
one IP number - which is often the case - this IP number is normally assigned to your PC -
leaving no connection available for your AXIS 2120. If your ISP is unable to provide you
with an additional IP number, there are a number of other options that you may like to
consider; including:

NAT Box

Short for Network Address Translation, NAT is an Internet s tandard that allows a
local-area network (LAN) to use one set of IP addresses for internal traffic and a second set
of addresses for external traffic. A NAT box located where your LAN meets the Internet
will handle all of the necessary IP address translations and provides:
• Internal IP addresses that are unique to your network - with no possibility of conflict with IP
addresses used by other companies and organizations.
• The possibility of combining multiple ISDN connections into a single Internet connection.
• An effective firewall for hiding internal IP addresses

NAT Feature in Windows 2000

Utilize the NAT feature in Windows 2000 to allow multiple Ethernet cards in your PC, an d
you can then use one port for the Internet and the other for your internal network. With
this solution, you can let your AXIS 2120 upload image streams to an external Web s erver
that is maintained and located with your ISP.
Note: For further details on Network Address Translation, see also RFC 1631.