Here, since it was wifi the "connectivity software" was with the OS and not from comcast. So when the cell card is unplugged we use wifi, when the cell card is inserted we can use that. I decline from writing more details but it does work here without fuss.
I use a Dell Inspiron 2200 with a comcast cable wireless connection. I would like to sometimes borrow my son's Verizon cell card for traveling. Can I put both sets of connectivity software on my computer without confusing it? Thanks for any help.