The way the firewall blocks the firewall protocol is by identifying the characteristics of the traffic data packet, such as port number, protocol type, data packet length, encryption method, and so on. Therefore, choosing a circumvention protocol that is not easily blocked by a firewall needs to have the following characteristics:

Strong encryption: Choose to use high-encryption over-the-wall protocols, such as Shadowsocks, OpenVPN and other protocols, which can effectively prevent traffic from being identified and interfered by the firewall.

Simulated traffic: Some protocols can be disguised as ordinary traffic, such as HTTPS, SSH and other protocols. These protocols will confuse circumvention traffic with ordinary traffic, making it difficult for firewalls to identify and block.

Support multiple protocols: Choose software or services that support multiple firewall protocols. When a certain protocol is blocked, you can quickly switch to other protocols to avoid being unable to bypass the wall because a single protocol is blocked.

In general, no circumvention protocol can completely avoid being blocked by the firewall, but choosing a suitable circumvention software or service, and choosing a circumvention protocol reasonably according to the actual situation can improve the success rate of circumvention.