4 steps to control bandwidth for users:
1. Identifying you (because simply they know which phone line you’re connecting from).
2. Counting your bandwidth usage (after identifying you, they keep a running count of how much data you send, and check whether you've exceeded your allowance before letting more traffic through).
3. Identifying international destinations (by using an IP address mapping database, they could map and figure out which country your destination traffic is in).
4. Policies (The Telco establishes a network policies to manage the access to which parts of the network, and at what time).
