Each I nternet (1) , called a host , is independent. Its operators can choose which (2) services to use and w h ich (3) services to make available to the (4) I nternet community . R emarkably , this anarchy by design works exceedingly well . IP is responsible for moving packet of data from (5) to node . IP forw a rds each packet based on a four- b y te destination (6) ( the IP address ). T he I nternet authorities assign range s of numbers to different organizations, T he organizations (7) groups of their numbers to departments . (8) is responsible for verifying the correct delivery of data from (9) to server . D ata can be lost in the intermediate (10) . TCP adds support to detect error or lost data and to trigger re transmission until the data is correctly and completely received .