Client                SOCKS Proxy               Server
   |                       |                       |
   | --------------------> |                       |
   |         SYN           |                       |
   | <-------------------- |                       |
   |       SYN+ACK         |                       |
   | --------------------> |                       |
   |         ACK           |                       |
   |                       |                       |
   | --------------------> |                       |
   |Version=5, Auth Methods|                       |
   | <-------------------- |                       |
   |       Method          |                       |
   | --------------------> |                       |
   |Auth Request (unless "No auth" method negotiated)
   | <-------------------- |                       | 
   |     Auth Response     |                       |
   | --------------------> |                       |
   | Connect Server:Port   | --------------------> |
   |                       |          SYN          |
   |                       | <-------------------- |
   |                       |        SYN+ACK        |
   | <-------------------- |                       |
   |      Succeeded        |                       |
   | --------------------> |                       |
   |       Data1           |                       |
   |                       | --------------------> |
   |                       |         Data1         |
   |                       | <-------------------- |
   |                       |         Data2         |
   | <-------------------- |                       |
   |          Data2        |                       |
                         ...