Authentication mechanism: SOCKS4 only supports TCP protocol while SOCKS5 supports TCP/UDP protocol,
supports various authentication mechanisms, server-side domain name resolution, etc.
Although SOCKS4A also supports TCP/IP, it only supports username/password authentication.
Network protocol: SOCKS4 proxy only supports IPv4 protocol,
while SOCKS5 proxy supports both IPv4 and IPv6 protocols.
link:http://www.piaproxy.com/?utm-source=crax&utm-keyword=?C01
supports various authentication mechanisms, server-side domain name resolution, etc.
Although SOCKS4A also supports TCP/IP, it only supports username/password authentication.
Network protocol: SOCKS4 proxy only supports IPv4 protocol,
while SOCKS5 proxy supports both IPv4 and IPv6 protocols.