ISP vs IP
ISP and IP are two terms commonly used when talking about internet connections. Although the two may seem pretty similar, they actually refer to pretty different things. ISP stands for Internet Service Provider, which is the company that provides the internet connection to you. In comparison IP is the more common term used to refer to an internet address with IP standing for internet protocol. An IP address is a unique identifier that is used to identify your modem to the rest of the world. An IP address is essential in order to route data to and from your home network. The router then sends the data to the specific computer on your home network.
If you are subscribed to an ISP, they often have contracts that extend for a fixed period of time. Unless you terminate your contract, for an additional fee, you are stuck with that ISP for the period. This can also be true with IPs as some ISPs provide a fixed IP for each subscriber. It can be changed, but again, you need to pay a fee to them. But in cases where the ISP uses dynamic addressing, the IP is actually leased for a short period of time. Typically 24 to 48 hours. If you are disconnected for longer than the lease time, the IP can be taken by another subscriber of the ISP. Once you connect again, you would be given a different IP by the ISP.
There is also the fact that IP addresses are as a result of the IPv4 design. Because of this, and the increasing number of ISP, it is expected that IP addresses well run out within a few years. Infrastructure to support the superior IPv6 design is already beginning to grow and in a matter of time, the whole internet would be migrated to the newer and roomier design.
Even if you are not connected to an ISP or the internet, you can still have IP addresses. Local networks have them for the same purpose; to have the ability to identify each computer in the network. This is essential for any network related activities like file transfers and such.
Summary:
1.ISP is the provider of the internet connection while IP is a unique network identifier
2.The ISP is always the same while some subscribers can have constantly changing IPs
3.IPs are limited while ISPs are not
4.IPs can exist without the internet while ISPs cannot