Use SOCKS proxy
So-called "Simple" client classes (TElSimpleSSLClient, TElSimpleSSHClient, TElSimpleSFTPClient, TElSimpleFTPSClient, TElHTTPSClient, TElSMTPClient etc.) that offer implementation of popular network protocols have a powerful built-in TCP socket that can connect via SOCKS proxies.
SOCKS proxies use SOCKS protocol, described in RFC 1928 and RFC 1929.
To enable SOCKS support, set the UseSocks property of the corresponding component to true. Be sure to enable only SOCKS or web tunneling, but not both. SocksServer and SocksPort properties specify the address and port of the SOCKS server. SocksVersion property specifies the expected SOCKS server version. Note, that versions 4 and 5 are not compatible with each other. Nowadays most SOCKS proxies support version 5 of the protocol.
If you need to authenticate on SOCKS server, set SocksAuthentication property. Provide a username in SocksUserCode property and a password in SocksPassword property.