On 15/08/2020 16:03, Turritopsis Dohrnii Teo En Ming wrote: > Good day from Singapore, > > I have a question. > > Is OpenVPN based on SSL VPN? > > I am looking forward to hearing from you soon. > > Thank you very much.
Just to extend the answers from Gert and Stefan M. a little bit. OpenVPN uses OpenSSL or mbed TLS for the cryptographic operations, as well as passing encrypted data between the local and remote side. But it does not use the plain SSL/TLS protocol. The OpenVPN protocol consists of two channels: Data Channel and Control Channel. The Data Channel transports the tunneled network traffic, using a symmetric encryption. This is plain binary data, wrapped together with some OpenVPN specific header information. The Control Channelis used to exchange configuration and authentication data and provides the needed data to derive the symmetric encryption key used for the data channel. Some modes of the control channel implies wrapping the standard TLS protocol into an OpenVPN specific packet format. The very first byte of each packet being transported over the wire identifies the "OPCODE" which indicates if the rest of the packet is a data or control channel packet. So depending on what you mean with "SSL VPN", OpenVPN may or may not be an SSL VPN. OpenVPN has its own protocol, but it does use the standard TLS protocol for some of its operation. -- kind regards, David Sommerseth OpenVPN Inc _______________________________________________ Openvpn-users mailing list Openvpn-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-users
