Naked DSL

A naked DSL (a.k.a. standalone or dry loop DSL) is a digital subscriber line (DSL) without a PSTN (analogue telephony) service — or the associated dial tone. In other words, only a standalone DSL Internet service is provided on the local loop.

The original concept of DSL was to use existing telephone lines for high speed data communication, with DSL and telephone services coexisting on the same phone line - but increasingly customers may require only the Internet service - and see no need for the traditional phone service.

In Regular DSL, data transmission is carried on inaudible high frequencies on a standard Plain Old Telephone Service (POTS) telephone line.

The original idea was to use existing telephone lines for high speed data communication. DSL and telephone service can coexist on the same phone line and do not interfere with each other. From the Telco's point of view, DSL gives them the ability to sell the same telephone line twice, to the same customer. It is an idea that benefits the telco (who makes more money) and the customer (who gets a high speed data connection without the need for installation of expensive new cables.)

Naked DSL is the same as standard DSL, except that there is no voice service. Telephone service is not required for DSL to operate correctly.

The primary advantage of Naked DSL is financial: the customer saves the expense of a phone line, which they may not need. In terms of equipment, physical setup and speed, there is no difference between Naked DSL and Regular DSL. They are identical, except for the absence of dial tone.

Telco Response to standalone DSL has generally been hostile.

In the United States AT&T allows Standalone DSL for its own customers, but only very reluctantly, and it blocks third parties from providing Standalone DSL over AT&T telephone lines unless those customers also purchase AT&T branded voice services. Verizon stopped permitting Standalone DSL for its own customers in 2014, but some third parties such as Brand X Internet do still offer it. Verizon's own customers are required to buy Verizon branded voice services in order to purchase any kind of DSL.

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Wikipedia