maximum protection

sorry if i didn't make myself clear. I'm trying to use one port for the cctv transmission,the system can be accessed remotely via broadband and can also transmit to a monitoring centre,any triggered alarm events.Broadband will only be used when a guard tour is selected for that site.The system will record locally. As well as this, i'm trying to send on a separate port, modem information, again remotely accessable but will communicate alarm events between two intruder alarm systems.One will be a central receiver and one the transmitter.My question is related to possible data conflicts/system crashes due to the data transfere.I understand that they will use separate ip addresses etc. but can a modem talk to another modem directly or will this idea not work.Any ideas????

hi guys, first timer on this site hope you can help me solve some design issues with an idea i have. Firstly loads of experience in the security alarm game but lagging behind on the pc based/cctv transmission side of the industry.Ok then my idea is this,I have access to a pc dvr manufacturer who has made a pci card and software package available which will record and transmit cctv footage locally and also can be copied remotely via the internet.I intend to use a broadband connection with static i.p. address's allocated to both pc units with a router at either end.This is straight forward enough, but is it possible to use the router to transmit data via the extra ports that are available on the units? I have seen a unit which will allow for communication between the routers(voice only)would i be able to transmit data by modem if i use a adsl filter at both ends.The reason for this is that i want to piggyback data transmission from the security system also located on site with the cctv system. any ideas?