Regards those IP address,
most internal networks run standard IP addresses ie 192.168.0.1 or 10.0.0.1 etc etc
its best to have a router as we all know, conected to the broadband line + setup.
The WAN ip address is what the client would type into explorer to find the system on the web. The wan ip comes from your ISP, it will be given to you as static or dynamic.
if dynamic it will change if the routers off for a few hours so you can use http://whatismyip.com/ to find it again.
Example of a 192.168.0.0-255 range
If the routers set to 192.168.0.1 then this will be the gateway address (internet gateway).
your PC`s, printers, servers and laptops can be 192.168.0.2, 192.168.0.3, 192.168.0.4 . . . . . . . up to 192.168.0.255
your CCTV ip address can be set with-in this range, best to put it higher up to keep it out the way of future pc`s being added. so lets set it at 192.168.0.50
so set DVR to IP=192.168.0.50 Subnet mask=255.255.255.000 Gateway=192.168.0.1
Next you will have to test things localy from the lan. from a laptop or other pc connected to the same lan enter the DVR ip address in the browser in this form http://192.168.0.50 (assuming DVR has webserver on port:80, most have) The DVR`s web page will be displayed, it may also download software to the pc first.
Next you will have to deal with the router which will have some sort of firewall that will block access to the DVR from outside the LAN ie Internet.
If the DVR is the only thing on the LAN you could set it as the DMZ (de-militerised zone), this will pass all internet traffic direct to the DVR with out and firewall. easy option but no security.
If there are other PC`s on the LAN then its definatly best to do it the right way. The destruction book for the DVR will give you a list of internet port numbers that the DVR will use. These ports then need to be un-blocked and directed to the DVR. This can be done in the routers settings.
one more thing, when you have to the WAN ip for the customer it will not work locally- you will get the routers log- on screen. to show the customer it working you would need a laptop with a seperate internet connection of its own ie 3g data card. or get the customer to call someone that is a a computer.
Loads of other things that can be pain DHCP,port-forwarding,double firewalls etc etc but thats the jist of it.
anyone think of anything to add?