DSL Modems Manufactures (ODMs, OEMs)

Greetings!

I'm working in a small start-up company. the work field of company is in IoT (Internet-of-Everything).
We want to find the name of companies are able to build DSL modems.
We want to order our own customized DSL modem in high quantity.
We are looking for ODM companies in DSL-Modems branch.

because our small company wants to build a special DSL-modem with new features.
the remind phase is: to embed our codes in new DSL-modem device.

If you know, please help me.

Thanks in advance