No special port. What is important, I understand, is where you live. You must be within a certain proximity of the appropriate Codetel facility.
For example, Dean Brown told me that homes in the Perla development would probably never have DSL because they live outside the service area.
I know when I applied for DSL, the first thing they asked me was where I lived. Until they verified it was within the service area, they wouldn't talk about giving me DSL.
(Just deleted the reference to Sea Horse Ranch. When I wrote it, I was thinking of Flash, not DSL.)