Internet Service Provider is the access consumers have to the internet. Commercial ISPs include companies like AOL. There are many regional ISPs, and students can consider their University as their ISP if that is how they access the internet. The connection between the consumer and the ISP is typically the slowest aspect of the internet (also known as the last mile problem). The ISP will then have a connection to the backbone of the internet, which is essentially a collection of larger ISPs (MCI, British Telecom, UUnet) via a T1 line or similar.