I am putting together a proposal for a client to use UC540s in 9 different mobile environments. Each will connect to the Internet independently and will likely employ SIP trunking for voice lines. Each individual environment needs to be stand alone - with an independent CME, CUE, DHCP, NAT, etc. The UC540 has (obviously) multisite capabilities, but these are designed for fixed applications where up to 5 sites will be in constant communication with one another. In our scenario, one or more of the 9 sites may be online or offline at any given time, but it is not likely that all 9 will be active concurrently. In the event that two of these sites are active, they may be active in the same physical location where an ethernet or phone cable can be stretched from one to another.
I am looking for an easy way to connect a combination of these vehicles together (probably only two at a time, but the two connected may vary depending on the situation) where they can employ 3 digit dialing from one extension to another from one vehicle to the other. I am not sure that the traditional multisite deployment would really work for this customer as there are 9 potential sites (instead of the 5 supported). Is there a way to connect two UC540s via their FXO and FXS ports and still acheive the same thing?
Thanks in advance,