It is said TCP is "Conection-oriented" does it mean all packets of one msg routed via same routers in between?

Question

It is said TCP establish a connection, what is the meaning of "Establishing a connection" ? Does it mean that a path is chosen thro which all packets should routed ( a dedicated path, like router 1, 2, 8,11 and 18 )?. or each packet routed Independently ?

Coz i confuesed as IP layer devices pass the packets thro whatever free paths. So How TCP and IP work together in that case?

Answer 1

LOL Without doubt, excellent in depth answers - wonders are they not too technical?

Summarizing:

1.TCP packets can flow as they wish not necessarily through same connection points in both directions.

2.“Connection oriented” simply means that protocol has build in mechanism which via both way communication make sure that all data is received by both endpoints (and for instance resented if something is lost in transit)... - as oppose to UDP protocol which is sort of "send and forget". "“Communication" simply implies exchange of information, while UDP is just one way data transmition.

Answer 2

If you map the TCP/IP protocol to the 7 layer OSI stack, the 'IP' piece is roughly equivalent to layer 3 while TCP is roughly equivalent to layer 4. In Transport Control Protocol (TCP) the two devices that are talking establish a connection that stays in place for as long as they talk (or something breaks). TCP also makes sure that it gets the conversation complete and accurate.



TCP will establish a path for the conversation and maintain it for the length of the conversation, and then break it. The actual path one conversation takes could be different from the path a different conversation takes.





Unigram Data Protocol (UDP), can in some cases be used in place of TCP. Packets are sent with no guarantee that they'll arrive or that they'll take the same path. To get a complete conversation, the receiving system(s) needs to reassemble the packets in to the proper order and request another transmission of any packets that don't make it. It is connectionless. Consecutive packets transmitted using UDP could take a completely different routes.

Answer 3

TCP itself does not establish connections; that is IP's job. IP splits the data stream into packets and routes it to the machine in question (and, yes, it's possible for all of the packets to take a different route, but it's not necessarily the case that they will). TCP is responsible for routing the reconstituted data stream to the correct port on the destination machine, and for handing it off to whatever protocol is in use (such as HTTP or FTP, for example).



TCP/IP is a layered set of protocols; each layer is only capable of speaking to the layers immediately above and below itself. This is why it has proven to be such a versatile system for communicating over heterogeneous networks with different data protocols, different wiring protocols, different transmission speeds and all that.