What is the best approach to serve a proxy auto-config file for Web Proxy Auto-Discovery RRS feed

  • Question

  • User409414831 posted

    I have the task to serve a proxy auto config file. It will be used with WPAD. The only requirement is to use IIS as webserver and ASP.NET core to dynamically modify/create the wpad.dat file on each request. The file will have different information based on the user/ip address of the request.

    We have about 10000 users in the network. What approach would be suitable for this requirement? My first thought was to create a webapi with a endpoint route as "wpad.dat". When the browser requests the file from servername/wpdat.dat url, the action in the api would create the file in memory from a MemoryStream and serve it to the browser. In memory and not from the file system/static file to avoid issues with locking the file on concurrent connections.

    As far as I know, WPAD will request the file on each restart and after clearing the browsers cache, so it could happen to have more or less 10000 concurrent connections to get the file. Is there a better/faster solution then creating the file in memory with a webapi on each request?

    Saturday, February 6, 2021 9:13 AM

All replies

  • User753101303 posted


    .AFAIK most companies are serving a single file as this is already a script file that can check the IP address (or blocks of address).

    Start maybe with an admin forum and explain there your final goal. There is likely a better approach than to serve a unique content to each IP.

    Tuesday, February 9, 2021 9:13 AM