public void ConfigureAuth(IAppBuilder app)
        {
            app.SetDefaultSignInAsAuthenticationType(CookieAuthenticationDefaults.AuthenticationType);

        app.UseCookieAuthentication(
            new CookieAuthenticationOptions { }
        );

        app.MapWhen(ctx => ctx.Request.Headers.Get("Host").Equals("abc.net"), app2 =>
        {

            app.UseOpenIdConnectAuthentication(
                 new OpenIdConnectAuthenticationOptions
                 {

                     ClientId = authClientID1,
                     Authority = authorityUrlAuth,
                     RedirectUri = redirectURL,

                 });
        });

            app.MapWhen(ctx => ctx.Request.Headers.Get("Host").Equals("def.net"), app3 =>
            {

                app.UseOpenIdConnectAuthentication(
                     new OpenIdConnectAuthenticationOptions
                     {

                         ClientId = authClientID2,
                         Authority = authorityUrlAuth,
                         RedirectUri = redirectURL,


                     });
            });

    }