how to capture network USERID

I've got an off the shelf application which is accessing an SQL database and retireving all sorts of corporate info etc. When you first launch the page the user is asked to put in initials and a password. This information is stored inside the SQL database and determines what the user can see & do to the other data. I would like to modify how this works so that when a user launches the page their network userID is used to determine their rights to the data. They are never prompted for a userID etc. I've got the database side of things all setup but I need to get the UserID. Ultimately the plan is to seemlessly incorporate this into part of our intranet.

Any help would be greatly appreciated. I apologize if my nomenclature is off but this all foreign to me.

This is a great start but it gives me the information in the following format:

domain\userId

Is there a way to isolate just the userID portion?

This is what I put in:


var sUserID = Replace(Request.ServerVariables("Logon_User"),"AHCD\","");

Where AHCD is the domain name.

I receive the following error:

Error Type:
Microsoft JScript compilation (0x800A03F7)
Unterminated string constant
/authenticate/login.asp, line 35, column 74

I've also tried it this way (as well as a half doxen other variants):

var sUserID2 = String(Request.ServerVariables("Logon_User"));
var sUserID = String.Replace(sUserID2,"AHCD\","");

With the same error.

I appreciate your help!

Hes using Jscript...