Connected: An Internet Encyclopedia
4.2.2.10 Simultaneous Open Attempts: RFC-793 Section 3.4, page 32

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4.2.2.10 Simultaneous Open Attempts: RFC-793 Section 3.4, page 32

4.2.2.10 Simultaneous Open Attempts: RFC-793 Section 3.4, page 32

There is an error in Figure 8: the packet on line 7 should be identical to the packet on line 5.

A TCP MUST support simultaneous open attempts.

DISCUSSION:

It sometimes surprises implementors that if two applications attempt to simultaneously connect to each other, only one connection is generated instead of two. This was an intentional design decision; don't try to "fix" it.


Next: 4.2.2.11 Recovery from Old Duplicate SYN: RFC-793 Section 3.4, page 33

Connected: An Internet Encyclopedia
4.2.2.10 Simultaneous Open Attempts: RFC-793 Section 3.4, page 32