Thanks for the recommendation Raj - in the short term we have customers with both Cache and IRIS and prefer not to have logic to determine which dlls to use.

I have Cache 2016.1 (not Ensemble or IRIS) and need to duplicate the functionality of this C# .net code. The target REST web service is a 3rd party not using Intersystems products.

public static TokenResponseModel getBearerToken(string siteUrl, string Username, string Password)
        {
            HttpClient client = new HttpClient();
            client.BaseAddress = new Uri(siteUrl);
            client.DefaultRequestHeaders.Accept.Clear();

            // uncomment to allow self signed certificates for https requests
            System.Net.ServicePointManager.ServerCertificateValidationCallback = delegate { return true; };

            HttpContent requestContent = new StringContent("grant_type=password&username=" + Username + "&password=" + Password, Encoding.UTF8, "application/x-www-form-urlencoded");

            HttpResponseMessage responseMessage = client.PostAsync("Token", requestContent).Result;

            if (responseMessage.IsSuccessStatusCode)
            {
                string jsonMessage;
                using (Stream responseStream = responseMessage.Content.ReadAsStreamAsync().Result)
                {
                    jsonMessage = new StreamReader(responseStream).ReadToEnd();
                }

                TokenResponseModel tokenResponse = (TokenResponseModel)JsonConvert.DeserializeObject(jsonMessage, typeof(TokenResponseModel));

                return tokenResponse;
            }
            else
            {
                return null;
            }
        }

Thanks for your response. Will this work if the REST web service I am targeting is a 3rd party not running Cache or using CSP?