Digital subscriber line service over loaded loops

Digital telecommunications exchange system

Digital telephone data and control signal transmission system

Digital telephone set

Digital telephone switch

Digital text messaging system and method

Direct access arrangement (DAA) circuit having automatic...

Direct connect modem deriving power from telephone line

Directionally-mapped, keyed alpha -numeric data input/output...

Directionally-mapped, keyed alpha-numeric data input/output...

Directionally-mapped, keyed alpha-numeric data input/output...

Directory delivery system and method for a digital...

Disclosing the receipt of new electronic message

Display for a telephone terminal

Distributed control teleconferencing voice bridge

Distributed splitter for data transmission over twisted wire...

Distributed splitter for data transmission over twisted wire...

Download booster for ADSL transmission

DSL communication system with improved bandwidth

DSL compatible load coil