How to use webdav in internet facing ASP.NET application

HI Experts,

I am having a requiremnet where I have to access some file in my asp.net application.
Now i was thinking to use the DSoFramer Ocx control for showing the file in the browser. as I will be storing the files on the server I need to have a access to the documents using a URL. So i thoguh webdav will be a better solution (I dont know much about webdav, just someone from my team suggested I am trying to use it)

My requirement is User should be able to search,view, edit or delete the documents in the ASP.NET applcaition. Along with the same I have the security levels on the document which is read only, modify and Admin.

So my question is it possible for make the webdav internet accessible having this security containts. I am really strglling with the security of the webdav.
I tried making it anonymous I am able to open a document in the activex control but I am not able to save it. Also due to anonymous access the webdav is accesible t anyone which i dont want.

I hope you got my problem, any pointer towards a different solution is also expected.
Also asp.net code examples to work with webdav is also welcomed.

PS. Client already rejected sharepoint which was my first solution to store the files.