Call a webservice via ssl and use a client pass

I call a webservice via HttpWebRequest. Now the owner of the service send a key and said I would need to use it in the future to access the serv开发者_高级运维ice via ssl.

Is there any way to use this key? The key itself is similar to the key when you prepare your server for ssl.

What sort of key have they provided? Assuming this key is an SSL client certificate, then the following link should explain everything you need to know about using it:

http://support.microsoft.com/kb/895971