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The concepts of connection-oriented and connectionless and the concept of multiplexing come to me in different chapters in Tanebaum's Computer Networks.

But after some thoughts, I feel that connection-oriented means reserving a path for a communication exclusively, and connectionless means allowing multiple communications do multiplexing in the form of time-division (specifically, divide a message into datagrams, and allow datagrams of different messages to travel a shared link in different times). So am I right that connectionless and multiplexing mean the same, and connection-oriented and non-multiplexing mean the same?

Thanks.

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No. These are two completely different, unrelated concepts. Multiplexing means that you are transferring multiple signals, and there are different ways of multiplexing. For instance many telephone systems use Time Division Multiplexing (TDM) but the telephone calls carried are connection-oriented.

  • Thanks. If a communication is connection-oriented, isn't a path reserved for only one communication? How can multiple communications share a path, i.e. multiplex? – Tim Oct 8 '15 at 23:44
  • That happens all the time. On a TDM line like a T1 for voice, each simultaneous call gets a limited time period. The call certainly lasts longer than the small time period, but it only gets to use the very small time period while sharing the line with other calls. – Ron Maupin Oct 8 '15 at 23:53
  • With TDM, what does connection-oriented mean then? Doesn't a connection reserve a path for a communication from the communication's beginning till its end? – Tim Oct 8 '15 at 23:55
  • Yes, but for most, or all of that path, the path can be shared, divided by time, for multiple calls. A standard phone call only needs 64Kbps, but a T1 line can multiplex a couple of dozen on that T1 line. – Ron Maupin Oct 8 '15 at 23:59
  • My confusion still exists. In TDM, do you break/pause a connection of a communication, to let other communication use the part of the path taken up by the connection, and then later resume the connection? I think, in connection-oriented service, a connection for a communication lasts from the beginning of the communication till its end, so it can't be paused to free the part of the path it takes up, and then be resumed. I looked up the concepts of connectionless and connection-oriented, but might not get their definitions correctly. Similar with multiplexing. Can you share your definitions? – Tim Oct 9 '15 at 0:07
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it sound like , connection-oriented or connection less are the conditions need to be meted before any signal transfer but multiplexing (TDM , FDM , CDM ...etc) are the way of transfer the signal after the link establishment.
connection-oriented means that the connection need to be granted from end to end before any data or signal transfer (TCP is connection orignted , source will never send the next session until the first one is granted to be delivered )
connectionless means no dedicated path or BW or end to end grantee is needed (UDP is connectionless protocol where all the session will be delivered regardless what session is doped) enter image description here
multiplexing is the way of send multiple signal on certain time interval or frequency range based on the type of this multiplexing
enter image description here

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By Tanebaum's definition, the internet is "connectionless". No dedicated, reserved path is created between any two nodes. A stream of packets are free (and often do) follow independent paths, per packet, and may be asymmetric -- flowing a different path in each direction.

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