Authorization VK + Django + backbone, how to check authorization on the server?

Question

Django

Hello. I decided to get a little twisted, I made friends with Dzhanga and Bekbon, through the REST framework. Now I'm thinking how to make authorization through VK.
On the face, using the VK api authorized the user, and I have his mid, sid and sig.
Now I can not understand how to implement authorization check on the server.
In general, thanks to the answerer, I went the other way. I authorized using the standard method by putting it in an iframe.
The iframe opens to the address of the VK authorization service, the service authorizes and redirects to a specific page (the page simply displays the received code) and since all this happens in the iframe, reading the code from it is not a problem.

Answer 1

In VK, the api token is bound to the IP address, therefore, you cannot make a request to the api from the server using the token received on the face. It is necessary to authorize the user on the server, not on the face.

Answer 2

How to authorize on the server but at the same time with Ajax?