When your using the internet the message your sending gets split into equally sized packets. These packets can get lost, to prevent this the inter-net makes a incompleat map of all computers within reach of all computers within reach. These computers are identified with an ip adress. TO make sure your packets don't get lost the computer that recives the packets will respond and to tell your computer it got them. Each packet has a nuber used to order it, like 1/27. Each packet will also contain a to and from so that they know where to send the acknowledgments. some of the problems that required these solutions are: missing packets, corrupted files, and no to or from.