Wireguard VPN over Hotspot

[CyberHermit]

My company is working planning on giving our entire staff a set of Samsung S22 phones. I'm currently in charge of making sure all of our main use cases work before purchasing phones and phone contracts. Currently I am trying to confirm that our team will be able to use their laptops over mobile hotspot. I have a test laptop I am using, it is able to connect and browse internet just fine when connected to samsung s22 hotspot but cannot connect to our corporate VPN. All of our laptops are Windows 11 will latest updates and are configured so they must always be on VPN (I'm able to temporarily disable VPN for testing purposes). Why does this not work on Samsung devices? I have tested using my personal Google Pixel 4 device and this scenario works fine. I have tested using my wifes iPhone 13 and this works fine. Only with Samsung devices does this not work. To confirm there was no special rejection of samsung s22 happening from our VPN server I setup a VPN connection directly from phone to server. This works fine too. Sadly because of android limitations laptop traffic over hotspot does not go through VPN using this scenario. We are using wireguard for VPN which transmit traffic using UDP protocol.

question: How do i make it so samsung s22 phone can turn on mobile hotspot and allow VPN traffic from Windows clients?

[-Robot-]

Can I ask that all the phone you tested, are on the same network provider?

I have tried it with cisco anyconnect with no issues, on Vodafone

[CyberHermit]

No they are on different networks. I am currently using the wireguard as our VPN. Its protocol VPN is different from AnyConnect. I believe AnyConnect is a TCP based protocol while wireguard is UDP based. Wireguard is much more friendly for mobile devices that change IP address's or work off of battery power.

[-Robot-]

So your test are invalid, you must compare them apples for apples. Try the same sim in each of the phone and see if your vpn is able to connect.

Cisco vpn use completely different protocols, and being is more widly adopted platform especially in a large corporate setting support could be different

Support for the Priduct by the network providers I am talking about

[CyberHermit]

I tried sim swapping to get the same carrier on all phones. I had some issues on pixel phone but iPhone worked without issue.

[CyberHermit · Accepted solution]

I've given up on getting this working. My current recommendation is that if you are using a phone that needs mobile hotspot connectivity and/or VPN just get an iPhone.

[TomComm]

Hello CyberHermit,

i am currently doing a lot of research on a solution for a problem similar to the one you described.

I have a Fritzbox at home on which I have set up Wireguard and connected it to my iPhone 13. The Wireguard connection from the router to the iPhone works without any problems.

I create a hotspot on my iPhone and connect my iPad to it. This works (I have internet) but I am not "connected" to the Wireguard VPN from my iPhone (I have not set up Wireguard on the iPad!).

What do I have to set up so that I am automatically connected to my Fritz router on the iPad via Wireguard over the iPhone hotspot?

[padames]

I have a Samsung Galaxy S24 and suddenly started having this same problem yesterday. I need to work remotely using a secure Internet connection. I used to be able to turn on my Mobile hotspot using my current data plan while the phone was on Mobile data and then use the laptop WiFi connection to access the Internet, start a VPN wireguard session and remote desktop and ssh servers in my office.
Now all of a sudden that does not work. I have compared using my wife's iPhone and to my surprise that works as expected.
What is the official Samsung answer? Wireguard is a common VPN software... could it be a setting I inadvertently modified? Why iPhone works?

[padames]

Any comments from Samsung? This is pretty bad for an expensive phone, the S24 Ultra (SM-S928W), that works very well otherwise. I am pretty sure this can be fixed if there is a will.
My phone has Android 14 with the kernel version 6.1.75-android14-11-2954398-abS928USQS4YB3
The Android Security patch level: Mach 1, 2025
My suspicion is that that patch is the culprit. I was perfectly able to use Wireguard to access my office VPN using my ISP internet data through the phone's mobile hot spot functionality before March.
Can somebody from Samsung test this and be our agent with somebody form the Android security team?