I believe I have solved it by adding this to the top of my MasterPage for the intranet site:

<script type="c#" runat="server">
public string Ip()
{
    string ipAddress = Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
    if (ipAddress == null || ipAddress == "")
    {
        ipAddress = Request.ServerVariables["REMOTE_ADDR"];
    }
    return ipAddress.Split('.')[0];
}

protected void Page_Load(object sender, EventArgs e)
{
    if (Ip() != "10")
    {
        Response.Redirect("http://www.internet-site.com/");    
    }
}
</script>

Any thoughts on this is highly appreciated..

Eaus,

So is the intranet and internet content in a different content tree?

Personally that's how I would have set it up - you can then mount the sites using IIS and host headers to have two completely seperate websites under the same Umbraco instance. Security / Access etc can then all be managed via IIS.

Cheers, Mark.

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