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grepfru_it on Feb 12, 2024 | parent | context | favorite | on: How SSH port became 22 (2017)

It’s just a data channel. This changed with nat and the introduction of the PASV command which allowed the client to set a non-well known port for the data channel

oarsinsync on Feb 12, 2024 [–]

> the introduction of the PASV command which allowed the client to set a non-well known port for the data channel

PASV instructs the server to specify another ip:port that it’s listening on to enable the client to connect.

PORT expects there to be an open port on the client for the server to connect to.

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