H1: I’m a Cambridge person. I want to use my Android device to access resources restricted to people on the Cambridge University network, but I’m at home or abroad or something. What do I do?

Use the Cambridge University Computing Service VPN service, which they call VPDN. Despite the fact that every other person has an Android device these days, the UCS specifically state that they do not support Android (and secretly would rather everyone still used Windows XP). However, they do support it – they just pretend not to be aware of it and are extremely resistant to being told that they do. Hence this FAQ entry, which they have been made aware of and refuse to put on their website, despite it being perfectly correct, legal, legitimate, etc..

Parts of this advice might work for other universities if they run a VPN service.

VPDN instructions for Android devices on the Cambridge network

  • Go to http://userforms.csx.cam.ac.uk/vpdn (Raven Login)
  • Fill in form requesting VPDN_USERNAME and VPDN_PASSWORD.
  • Wait for UCS to send you these by regular mail.
  • From a terminal, type: ssh -x [email protected] then:
    Login    : VPDN_USERNAME
    Password : VPDN_PASSWORD
    Press C <enter>
    Press K <enter>
    The SHARED_KEY will be displayed. Write it down, then logout.
  • Install the Android app ‘VpnCilla‘ from the Google Play store (costs about 3 UK pounds) on your device. This is the only such app I could get to work, and I did try quite a few of them.
  • Start VpnCilla.
  • Add a new connection by pressing the + sign.
  • Type a name for the new connection e.g. ‘Cambridge VPN’ or whatever you like.
  • Type in the following connection settings:~

    VPDN Server Address    : vpdn-access-cisco.csx.cam.ac.uk
    Group ID               : vpdn
    Group Password         : SHARED_KEY
    Your Username          : VPDN_USERNAME
    User Password          : VPDN_PASSWORD
    VPN via mobile network : <tick the box>
    Optional vpnc flags    : --enable-1des

    NB: I had to *guess* the Group ID was ‘vpdn’ – the UCS don’t seem to give you this information, which is presumably one reason why Android devices are ‘not supported’.
  • That’s it.

To make things easier there is a VpnCilla ‘Widget’ in the App Locker that you can add to your homescreen; this can be used to toggle the VPN connection on and off with one click. You can also rig this to start automatically when you turn on the phone, so that VPN is effectively ‘Always On’.

Result: your phone/tablet now always acts like it’s plugged into the wall in the Cavendish Laboratory wherever it might happen to be physically, so you can read Physical Review Letters on the beach just by pressing a PDF link, rather than pressing the PDF link and spending the next 10 minutes scrolling through menus and filling in forms.


Please log in to rate this.
0 people found this helpful.

Category: H: Miscellaneous

← Frequently Asked Questions

Leave a Reply