China’s strict online policy has gotten tougher, and the country’s new internet restrictions will impact networking vendors and customers.

The Chinese government has ordered state-owned internet service providers to block access to three types of Transmission Control Protocol (TCP) ports: 80, 8080 and 443. The former traditionally hosts HTTP traffic while 8080 and 443 traditionally host HTTP traffic. Blocking the ports is a way to block VPNs, which many people in China use to circumvent tight internet censorship.

The official word on the ban was that it would go live in February, but a letter obtained by SD-WAN Experts and Network World last week shows the government telling one of the ISPs to have the restrictions ready by Thursday. China’s state-run newspaper denied the date change and cited anonymous sources from the ISP, China Telecom, as evidence. But the ban is coming within the next two months, and businesses are bracing for the consequences.

SD-WAN providers are in a pinch because the restrictions block “site-to-site” VPN use. That’s not a bright outlook for a technology that specializes in connecting remote offices to the same network. VPN Compare says businesses might regain access to the VPN ports if they make a special application to the ISPs but will likely have to wait until the necessary surveillance of their Internet use is “put into place.”

China drew backlash from the international business community when it introduced its plans to further curb VPN use. Bloomberg this summer detailed the various problems that come with the restrictions. Losing VPN access is not just an issue for SD-WAN. It generally impacts the ability of businesses to securely and quickly put workloads into the cloud.

Torsten Weller, a business development associate based in Beijing, told Bloomberg that China is fighting an impossible battle by removing access to particular servers. “The restrictions might well intensify, but the only sure way to completely shut down VPN use would be a complete disconnect from the outside world,” Weller said.