Contention is always a potential issue somewhere. Even a leased line dumps you on the open network eventually. Your typical 'broadband' connection is always contended right from the get go. It's not something that will ever go away. Being contended isn't itself a problem - the problem is if part of a network becomes over subscribed.
All that contention means is There isn't enough bandwidth available for everyone who might want to use the link if they all choose to use it at the same time.
In reality everyone doesn't tend to use the same link fully at the same time. While you're downloading a web page, I'm reading a web page and vice versa. Even streaming media rarely uses the full capacity of a link all the time these days.
It's a question of management. Generally speaking the more expensive ISPs do a better job of managing their network but most aren't too bad these days anyway. A lot of services in life in general are contended. Hospitals, restaurants and roads are all contended. It's just a matter of good planning and management to avoid issues.
Edited by Andrue (Mon 28-Oct-13 07:32:48)