Performance Expectations

I’m wondering if anyone can help me understand what I should expect for performance with ZIA. I know that’s a loaded question and the answer will vary. But if I have a user with a 1Gbps link and I get them to go to speedtest.zscaler.com it shows that they’re getting 40 Mbps down/40 Mbps up. Everything is working reasonably fine, but then I get asked “It should be faster than this, shouldn’t it?” I don’t have an answer for them because I truly don’t know what we should be expecting. This is causing some churn because I don’t know if I’m chasing down a performance problem or not. If some folks can share their experiences I would love to hear them. Thanks!

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Should be 10x faster at least. Which OS? Which tunnel version? The technical limit is based on the ZENs the client is connected to and how busy the specific ZEN is at that time. Zscaler staff can tell more. Have you seen this article Measuring the Performance of the Zscaler Service | Zscaler

You may also check ZTunnel 2.0, DTLS/TLS, MTU - #3 by manuel. It helped a customer once. I would also recommend creating a ticket.

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Definitely open a support ticket. I have asymmetrical 100mbs service from Optimum and I get a result that’s close to my data plan. This is with ZT 2.0 DTLS. Also be aware that we have had reports of some ISPs throttling DTLS / 443 traffic. Try it with TLS and see if there is a difference.

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This is a really tricky topic with so many variables in play that you just have no control over. In particular the ZEN nodes you are using. you have no idea how busy they are, the DC utilization etc. I feel your pain. My personal experience is that you will get the answer along the lines of “you should have enough bandwidth to work”. They will never give you a number.

In your scenario where a user gets 40Mbps UP AND 40Mbps DOWN that is plenty for the average user. There isn’t really a problem it is just people having the wrong expectations. E.g “i get 1 Gbps at home from my ISP therefore I should get 1Gbps via Zscaler” - not correct.

Are you aware about the localhost test at http://127.0.0.1:9000?ztest?q=@example.com (replace example.com with your domain). at least you can compare DIRECT with via the ZEN and see what the variation is?

Thanks for the replies everyone. It seems as though the problem is either with Microsoft Surface hardware in general, or something with the Windows 10 image that is deployed to the corporate fleet. When I run the Zscaler speed test on my corporate laptop, I get 40 Mbps down/40 Mbps up. When I run the Zscaler speed test on my gaming computer (running Windows 11), I get 250 Mbps down and / 29 Mbps up. It’s quite inconsistent. Both are wired Ethernet connected to the same switch. Very strange.