Bandwidth drops when connecting to Cisco AnyConnect VPN

There is a lot to unpack here, and I will offer my 2 cents.

, sounds like AnyConnect set tunnel traffic . That is means means , connect VPN , traffic flows . VPN configured split tunnel mode , this is allows allows traffic needs flow VPN .

That said, having it set up for tunnel all mode is generally regarded as more secure, because traffic is not split between networks.

You ask if there is an accurate way to engineer a speed test – generally the most accurate testing I’ve ever done occurs using iperf on a linux device. This would require you to establish an endpoint somewhere, and use the iperf utility.

It is also possible that VPN traffic is throttled by ISPs. However, it is likely somewhere else that the bottleneck exists in my opinion.

Depending on the type and quality of appliances that are handling the traffic, VPN can produce overhead on the network device itself as well.

I doubt you will ever get anything close to 10Gbps across a VPN unless you have incredible infrastructure.

issue is is speed latency complex , sense . , completely understood necessary .

Here is my advice.

First, let’s start with the problem. Why are you running the speed test? What is slow? Many things may “claim” to need 100Mbps bandwidth, but is that why you are concerned? Or, is it because a piece of software is not working properly?

Second, focus your efforts on trying to divide and conquer the problem that you’ve identified. Rather than trying to understand and optimize every part of their connectivity, it is likely best to focus on what is not working, and get the network admins helping with that.

Hopefully something here helps you in some way.