Hi everyone
whenever two system communicate by means they exchanging message .Is there entire layer stack of both system
involve in exchanging information ? Is there some case in which some layers are not works and do not play a role to exchange information
between two system?
when someone says I send a TCP segment or IP segment means what he is talking about software point of view?
and one more thing this is also confusion for me tcp frame ,tcp packet, tcp segment what is appropriate place for these keyword .Are they same ?
anyone help me to explain please

I am not totally sure but something must initiate the connection and mostly it is a peace of software like icq or the router os.

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UI requests are generated from layer 7. i.e. you interacting with your computer. these types use all 7 layers of the OSI protocol stack. Thing like routing protocols usually don't use anything higher then the network layer or transport layer. there is no need.

as for
tcp frame ,tcp packet, tcp segment

tcp frame is the structure that a TCP data must be in to make a tcp packet.
it includes a bunch of info: source port, destination port, checksum, data, etc
IP headers are added to the tcp frame to make a tcp packet including source and destination IP address
when the packets are very large, the data is fragmented into smaller segments. tcp segments,
then formatted into tcp frames, ip headers are added to make tcp packets.
then the data is sent, and packet reassembled on the receivers end

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"If you're good at anticipating the human mind. It leaves nothing to chance."
-Jigsaw

Generally the terms are:
TCP segment (Layer 4)
IP packet (Layer 3)
Ethernet (or other Layer 2 technology, Frame Relay, PPP, etc.) frame

This is what the cert exams expect you to know - TCP frame and TCP packet don't figure in anything.

Aubrey

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The illiterate of the 21st century will not be those who cannot read and write, but those who cannot learn, unlearn, and relearn. Alvin Toffler, "Future Shock" 1970

encapsulation is the magic word, the idea is to separate steps of a communication. it's cleaner in code and easier to maintain.
ethernet/ATM communication for example is pure is layer 1-2 communication.
ARP includes imho first 3 layers.
BGP, OSPF, EIGRPG or http for example would be more or less "all layer" protocols.

But note that it's possible to encapsulate low layer protocols as payload on higher or equal layer protocols. PPPoE/PPPoA is going this way for example.
makes it more interesting, eh

thanks a lot friends to explain me ........