Hello Mohamed,
I am a little confused about what exactly you are asking for.
In case you want to access the internet with a DSL connection the 1600&1700 routers will be able to do this utilizing PPPoE. Have a look at "PPP over Ethernet Client"
http://www.cisco.com/en/US/products/ps6350/products_configuration_guide_chapter09186a0080087b40.html
In case you are looking for a carrier class provider router for broadband aggregation, those two are not the first choice.
Hope this helps! Please rate all posts.
Regards, Martin