Cisco anyconnect and OpenConnect
Cisco AnyConnect and OpenConnect are two different VPN systems that allow secure communication between computers over public or shared networks. The primary differences between Cisco AnyConnect and OpenConnect are their features, cost, and device compatibility.
OpenConnect is a high-performance and lightweight VPN server, highly resistant to DPI and DPI-blocking, meaning that it is nearly never blocked by proxy servers or firewalls. It also has full compatibility with the official Cisco AnyConnect clients, features a packet format indistinguishable from a standard HTTP connection, and is open-source, meaning both robust portability to new platforms and nearly no operating costs. Beyond just clients and servers, the OpenConnect project also features a NAT-traversal library intended for developers of applications that need to communicate directly with each other on an internet-distributed network, using either IPv4 or IPv6. OpenConnect is resistant to DPI by its packet format: it generates an encrypted connection indistinguishable from a standard HTTPS connection and incurs no prediction bias due to it being encrypted. OpenConnect is highly resistant to censorship because it is highly resistant to DPI and DPI-blocking, meaning that it is nearly never blocked by proxy servers or firewalls.
OpenConnect is designed primarily for use in internet-distributed network environments to connect remote clients securely. However, it is also strongly recommended that a VPN server protect application communications, specifically in environments with network characteristics such as firewalls, that might otherwise prohibit or block through-tunnels. OpenConnect is a VPN server that uses the OpenSSL library to implement the SSL/TLS protocols. It is designed to be small and easy to configure. It supports a wide range of client operating systems, including Windows, Mac OS X, Linux, and android and IOS.