Network communication between three computers using SSH

1

Say I'm on computer A and I use SSH to get a console on computer B. Then through this SSH console I copy files from computer B to computer C.

                                    ME (Computer A)
                                    |
                                    | (ssh to)

                                  Computer B       ---------->       Computer C
                                                  (copy files to)

What network traffic comes over the wire to me and my console and what traffic only moves between computer B and computer C? Is my assumption that the copied files' data only moves between B & C and not A & B?

nsg

Posted 2013-04-09T16:36:23.123

Reputation: 113

not a question, and yes, you'll probably want to redirect all output to of the copy/xcopy operations with >/dev/null to minimize every bit of bandwidth from console output to your terminal. – Marcel – 2013-04-09T16:42:46.683

Answers

1

Yes, your assumption is correct. B and C have no knowledge of A. As far as C is concerned, a user from B is launching (I assume) an scp command and tranferring files from C to B. Whether that user has logged in from A or Yor Z is completely irrelevant. At that moment the user is on B and that is all that C will know.

So, any transfer between B and C is just that, a transfer between B and C, completely independent of A. The only exception transfer is of the few bytes of output displayed on your terminal. Those are the only things that are transferred back to A to be displayed on your screen. The actual files never touch A.

terdon

Posted 2013-04-09T16:36:23.123

Reputation: 45 216