It depends on logic that you use. In Master page give id for all links. And in page load event based on user type make visibility of the links false. Your user type can be session or cookies.
Eg:
Source code
<div>
<asp:HyperLink ID="hlinkAdmin" NavigateUrl="~/Admin.aspx" runat="server">Admin</asp:HyperLink>
<asp:HyperLink ID="hlinkUser" NavigateUrl="~/User.aspx" runat="server">User</asp:HyperLink>
</div>
code behind:
public string uType="Admin";
protected void Page_Load(object sender, EventArgs e)
{
string errorMsg = "";
if (uType == "Admin")
{
hlinkUser.Visible = false;
}
else if (uType == "User")
{
hlinkAdmin.Visible = false;
}
else
{
errorMsg = "Not logged in";
}
}
Hope it helps you.