Real,
I have Windows RT 8.1 and I don't see anything in the VPN connection properties indicating "full" support for IPSec groupname+password authentication, which is essentially what most companies using Cisco VPN seem to utilize. I could be wrong and I even hope I'm wrong, but I don't think so.
This link is frequently referenced:
http://technet.microsoft.com/en-us/library/jj900206.aspx
...but the only IPSec authentication supported is still through a certificate or pre-shared key.
Feel free to post a screenshot of the appropriate Win RT 8.1 dialog to prove me wrong. Please prove me wrong.
Since you have Windows RT device, can you do all of us a favor: call Microsoft support, ask them what they got to say about VPN from various vendors (Cisco, Juniper, Checkpoint etc.) and let us know what is their take?
Surface Support
Toll free: (800) Microsoft or (800) 642-7676
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