What if I have an internet content filter or firewall?

Last updated August 3, 2026

If a content filter or firewall is on your network or computer, allow (whitelist) the following so Blink Session and its video calls work:

The domain of this site (and your organization's Blink Session domain if it's custom).
The video service domains: *.opentok.com, *.tokbox.com, and *.vonage.com.
Secure real-time (WebSocket) connections over wss:// on port 443.

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