topic Clarification on http2 traffic and decryption in General Topics

Clarification on http2 traffic and decryption

KGDrake — Thu, 22 Jun 2023 19:49:00 GMT

Hi all,

I was hoping to get some clarification on http2 and firewall interaction. I understand that generally http2 works without issue as long as it's being decrypted. I also understand disabling inspection/decryption (Strip TLS ALPN) on http2 traffic can cause it to be downgraded to http1, thus defeating the purpose. But what if there's simply not a decryption policy attached to a rule that sees http2 traffic? Does it just pass it along as http2 without deep inspection? Or does the http2 have to be decrypted for it to pass properly?

Re: Clarification on http2 traffic and decryption

kiwi — Fri, 23 Jun 2023 10:00:39 GMT

Hi @KGDrake ,

It won't see it as http2 traffic. Without decryption, the firewall will classify this traffic as ssl traffic.
If you disable http2 inspection is will be classified as unknown-tcp.

Kind regards,

-Kim.

Re: Clarification on http2 traffic and decryption

MP18 — Tue, 15 Apr 2025 16:32:04 GMT

@kiwi When you say traffic is classified as unknown-tcp it is when SSL decryption is enabled but HTTP2 is disabled right?

Regards