Transport
    Client              Converter              Server
       |SYN, MPC           |                      |
       |[->Server:port]    |         SYN, MPC     |
       |------------------>|--------------------->|
       |<------------------|<---------------------|
       |SYN+ACK, MPC       |      SYN+ACK, MPC    |
       |[MPC supported]    |                      |
       |------------------>|--------------------->|
       |     ACK, MPC      |        ACK, MPC      |
       |        ...        |          ...         |