The NTL network runs through transparent proxy servers. Up to 15 server addresses host each area. These transparent proxy servers also override the user's hosts file and prevent manual DNS updates. This makes it easier for NTL to provide a more reliable connection as well as being able to monitor traffic requirements in each area. This also causes many problems for websites which record IP addresses to ban and/or track users. This means that if a website bans one offender, it bans everyone in the same area. Also, many on-line games automatically ban IP addresses with multiple usernames associated with them. Small-scale games do not cause too many problems, but when friends attempt to spread the game around, the system prevents everyone (including the original player) from using the game.