Multiple clients and a server can run simultaneously, 27 encryption methods
DES-CBC 64, RC2-CBC 128, DES-EDE-CBC 128, DES-EDE3-CBC 192, DESX-CBC 192,
BF-CBC 128, RC2-40-CBC 40, CAST5-CBC 128, RC2-64-CBC 64, AES-128-CBC 128, AES-128-CFB 128, AES-128-CFB1 128, AES-128-CFB8 128, AES-128-OFB 128, AES-128-GCM 128, AES-192-CFB 192, AES-192-CFB1 192, AES-192-CFB8 192, AES-192-OFB 192, AES-192-CBC 192, AES-192-GCM 192, AES-256-GCM 256, AES-256-CFB 256, AES-256-CFB1 256, AES-256-CFB8 256, AES-256-OFB 256, AES-256-CBC 256
XFRM, IKEv1, IKEv2, with 14 encryption methods for IPsec (3DES, DES, AES128, AES192, AES256, AES128GCM8, AES192GCM8, AES256GCM8, AES128GCM12, AES192GCM12, AES256GCM12, AES128GCM16, AES192GCM16, AES256GCM16)
GRE tunnel, GRE tunnel over IPsec support
Client/Server instances can run simultaneously, L2TPv3, L2TP over IPsec support
Proxy designed to add TLS encryption functionality to existing clients and servers without any changes in the program’s code
Method of building scalable IPsec VPNs, Phase 2 and Phase 3 and Dual Hub support
SSTP client instance support
ZeroTier VPN client support
WireGuard VPN client and server support
Tinc offers encryption, authentication and compression in it's tunnels. Client and server support.