Yes I would reccommend changing your cable and phone servivce to the same company as you will usual be able to pay less for both of them together. The cable providers have a excellent digital phone service.
Comcast Digital Cable Service has the most poular telephone service in Chicago.
Digital phone service uses exisiting phone lines. VOIP service uses your internet signal.
Digital signal conversion is done on the telephone unit itself. Whether it is a call forwarding service or not.
technologies that are used in telephone exchange include manual service, dial service, telephone exchange and telephone switch. Other services include concentrator, off-hook, on-hook and wire center.
A modem/router
http://wiki.answers.com/Q/How_is_the_data_and_imformation_transimited_over_public_telephone_network,public switched telephone networks and intergrated service digital networks.
Integrated Services Digital Network (Integrated Services Digital Network) An international standard for switched, digital dial-up telephone service for voice and data.
It can often seem difficult at times to find the best telephone service. With so many different telephone service providers to choose from, finding the best one for your can be challenging. Try to find the best deal on your telephone service. You can typically get a phone home line nowadays for much less due to the advent of digital phones. Consider how much you use long distance service when making this decision.
Digital Service Line Access Multiplexer.It's the box in the exchange that connects between the telephone system and your Digital Subscriber Line (DSL), usually Asynchronous DSL (ADSL).
This site is not a telephone directory service!This site is not a telephone directory service!This site is not a telephone directory service!This site is not a telephone directory service!
You can try their customer support, telephone 1-800-235-6325.
By digital phone service, I would assume you mean a land line telephone. The services available might vary based on your location, but Verizon and Comcast are two companies I know of that offer land line service in most parts of the US.