LET US CONSIDER A NETWORK AS, A------B------C------D------E AND A IS SENDING MESSAGE TO E
A is source and E is Destination....
Hosts are A and E
Hops or Nodes are A,B,C,D,E
Ends are the processes in layers which are communicating ( web processes in Transport Layer of 'A' communicating with web processes in Transport Layer of 'B' )
hop-to-hop by Data Link Layer
Host-to-Host is Network Layer
End-to-End is Transport Layer