Cordless Telephony Profile (CTP)

CTP defines how a cordless phone can be used over a Bluetooth wireless link.

Usage Scenarios

Used for either a dedicated cordless phone or a mobile phone that acts as a cordless phone when in proximity to a base station implementing the CTP. It is anticipated that mobile phones could use a Bluetooth CTP gateway connected to a landline when within the home, and the mobile phone network when out of range. CTP is central to the Bluetooth technology '3-in-1 phone' use case.

Example Products

Here are a few examples of the types of devices that you might find using the CTP:

• Laptop
• PC
• Handheld Cordless Phone
• Mobile phone
• PDA

Getting Technical

The CTP defines two roles, that of a Gateway (GW) and a Terminal (TL).

• Gateway (GW) – The GW acts as a terminal endpoint from the external network point of view and handles all interworking towards that network.
• Terminal (TL) – The TL is the wireless user terminal, which may, for example, be a cordless telephone, a dual-mode cellular/cordless phone or a PC.

In the profile, the interfaces in the Figure to the left are used for the following purposes: A) The Call Control entity uses this interface to the speech synchronization control to connect and disconnect the internal speech paths. B) This interface is used by the GW to send and by the TL to receive broadcast TCS-Binary messages. C) This interface is used to deliver all TCS messages that are sent on a connection-oriented (point-to-point) L2CAP channel. D) This interface is used by the Call Control entity to control the Link Manager directly for the purpose of establishing and releasing SCO links. E) This interface is used by the Group Management to control Link Manager functions when initializing and for key handling purposes. F) This interface is not within the scope of this profile. G) This interface is used by the Group Management entity to control the LC/Baseband directly to enable inquiry, paging, inquiry scan and page scan. Need more? View the Cordless Telephony Profile (CTP).