VPN and Coffee shop

Discussion in 'Mac Basics and Help' started by max2, Oct 30, 2018.

  1. max2 macrumors 68030

    May 31, 2015
    Is it possible a coffee shop can disable or prevent VPNs from connecting to it?

    WiFi works without VPN otherwise
  2. jeremysteele macrumors 6502

    Jul 13, 2011
    It is possible. I've been to hotels that have pulled nonsense like that before. The usual ways they do it are:
    • Blocking specific outgoing ports used by your VPN (by far the most common way)
    • If they provide DNS via DHCP, they can block requests to your VPN's hostnames
    • Detect and prevent packets with security handshakes - which would essentially stop you from have a secure connection anywhere.
    Why they do it, I dunno. But it is technically possible.
  3. max2 thread starter macrumors 68030

    May 31, 2015
    Thanks anyway around it?
  4. maflynn Moderator


    Staff Member

    May 3, 2009
    Yes, use cellular data and not use the free wifi. Its their wifi, and their rules ¯\_(ツ)_/¯
  5. max2 thread starter macrumors 68030

    May 31, 2015
    That what I did!

    Found a way around it though! :)
  6. simmonsj macrumors newbie


    Aug 24, 2010
    Newcastle upon Tyne, UK
    A lot of VPNs will use standard internet ports - most likely 443 for a secure connection (there may be some UDP ports required too). Coffee shops will have 443 open otherwise you couldn't hit a secure website (but they could block it in other ways as described above)

    Not every VPN uses these ports though so if the coffee shop has blocked other ports then you might have problems. I know one free VPN product I've used before didn't use port 443 (there was a paid-for version of the product that enabled that. ofc.)

Share This Page

5 October 30, 2018