github.com/sagernet/sing-box@v1.9.0-rc.20/docs/configuration/route/sniff.md (about)

     1  If enabled in the inbound, the protocol and domain name (if present) of by the connection can be sniffed.
     2  
     3  #### Supported Protocols
     4  
     5  | Network | Protocol | Domain Name |
     6  |:-------:|:--------:|:-----------:|
     7  |   TCP   |   HTTP   |    Host     |
     8  |   TCP   |   TLS    | Server Name |
     9  |   UDP   |   QUIC   | Server Name |
    10  |   UDP   |   STUN   |      /      |
    11  | TCP/UDP |   DNS    |      /      |