General Networking/Lan/Wan/Static IP and VPNs


I recently changed my ISP and everything works like a breeze until I have to connect to my office VPN. Whenever I try to connect to my office VPN via Junos Pulse, I am able to connect to it, but there's no internet access right after that. On asking my ISP help desk, they said that my IP is dynamic and changes all the time, thus not allowing me to stay connected to the internet. They have also asked me to subscribe for a static IP to solve this issue. I just wanted to cross check if this is true or not, because I can easily connect to my office VPN when I try using my phone's 4G connection as a WiFi hotspot. The problem is only encountered when I'm using my ISP's broadband connection. Thanks.

Hi Ashish,

A dynamic IP address changes every so often, as compared to a static IP address, which never changes. Normally, a changing IP address does not cause any problem until you try to connect to a local device from outside of your home network.  Or ... to connect to the Internet once you established a VPN.  With a constantly changing IP address, you may be able to connect a few times, but not after the IP address updates.

But ... what you wrote - and please Confirm and Validate this is "your Internet connection NEVER works at home using your ISP once you establish your VPN.  If this is true then it is NOT because of dynamic IP Addressing.  Your IP address will NOT change constantly.  It might change every hour or every several hours but certainly not all the time.  If it did you would have issues all the time with your Internet connection.

It is easy to test that out - just google "what is my IP address".  And copy/paste the number into some type of application - like notepad, etc.  Do it again and again every 5 min for several hours.  I would be willing to bet that it probably doesn't change at all or only once here and there - as long as you have been active on the Internet.

As far as I'm concerned your ISP is lying about the "constantly changing IP".  It just doesn't work that way.  I've been doing this a long time.  They are probably trying to sell you something.  I would honestly be pretty surprised if they "gave you a static IP" and your VPN worked afterwards.  It could be worth trying, as long as your company is willing to pay for the difference.

Thing is - a VPN may be easily configured to deny Internet use once a VPN is established.  If that is true then it should never work - for your ISP - or for your phone hotspot.  You implied that this might work when you use your phone as a hotspot?  Sorry but you weren't very specific about that.  Please connect to your VPN using your phone's hotspot, then see if you have an Internet connection and write back your results.

It sounds to me like there could be something going on with the security settings related to your ISP.  It could be your wireless router, your cable/dsl modem, or even something inside the ISP itself.

I assume that you have talked to your companies IT helpdesk, correct?  What have they been trying to help you diagnose the issue?

I look forward to hearing more.  Thanks!


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Jeff K


I'm a Network and Application Performance Specialist, and have worked for some of the best software companies in the world.


I have over 20 years in Information Technology & Networking.

Lots of hard work, study and real-world experience. I've had some formal training along the way but most of my knowledge is from working in the field, not the classroom.

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