What does it mean for TCP to be connection-oriented in the transport layer?

[lostinxlation]

Hi

I was reading the network book the other day and it said TCP was a connection-oriented protocol, and I'm now puzzled with what connection-oriented means in this instance.

I understand what connetion-oriented means in general. In the data link layer, connection-oriented communication such as ATM, Frame-Relay and telephone conversation set up the communication path first, transfer the data along that path, and tear down the path after the data transfer is done. The data flows on the same path which is set up in advance. It's very clear what connection oriented means in such a case, but I can't see a clear picture about connection-oriented in transport layer, TCP.

TCP(or any transport layer entities) doesn't specify the communication path, right ? How could TCP be connection-oriented ?

 

[waht]

Hi

I was reading the network book the other day and it said TCP was a connection-oriented protocol, and I'm now puzzled with what connection-oriented means in this instance.

I understand what connetion-oriented means in general. In the data link layer, connection-oriented communication such as ATM, Frame-Relay and telephone conversation set up the communication path first, transfer the data along that path, and tear down the path after the data transfer is done. The data flows on the same path which is set up in advance. It's very clear what connection oriented means in such a case, but I can't see a clear picture about connection-oriented in transport layer, TCP.

TCP(or any transport layer entities) doesn't specify the communication path, right ? How could TCP be connection-oriented ?

TCP is a bit sophisticated protocol which ensures that all data packets are received. If some particular packet is lost TCP will ask the transmitting end to send it again until all packets are received in full. To accomplish this the two-ends have to talk to each other back and forth. In order to do that they have to be initialized that a TCP is to be used. That's why it's called connection-oriented.