diff --git a/lib/chronoscope/nts/key_establishment_client.ex b/lib/chronoscope/nts/key_establishment_client.ex
index bf1b77c..a410b2e 100644
--- a/lib/chronoscope/nts/key_establishment_client.ex
+++ b/lib/chronoscope/nts/key_establishment_client.ex
@@ -10,7 +10,8 @@ defmodule Chronoscope.NTS.KeyEstablishmentClient do
   def key_establishment(%{host: host, port: port}) do
     case ssl_connect(host, port) do
       {:ok, socket} -> perform_key_establishment(socket)
-      {:error, {:tls_alert, {:handshake_failure, error}}} -> {:error, to_string(error)}
+      {:error, {:tls_alert, {:handshake_failure, error}}} -> {:error, String.trim("#{error}")}
+      {:error, {:tls_alert, {:no_application_protocol, error}}} -> {:error, String.trim("#{error}")}
       {:error, :timeout} -> {:error, :timeout}
       {:error, error} -> {:error, inspect(error)}
       error -> {:error, inspect(error)}
@@ -18,7 +19,9 @@ defmodule Chronoscope.NTS.KeyEstablishmentClient do
   end
 
   defp ssl_connect(host, port) do
-    :ssl.connect(host, port, tls_options(host), @timeout_in_milliseconds)
+    host
+    |> String.to_charlist()
+    |> :ssl.connect(port, tls_options(host), @timeout_in_milliseconds)
   end
 
   defp tls_options(host) do
diff --git a/lib/chronoscope_web/controllers/api/v1/nts/key_establishment_controller.ex b/lib/chronoscope_web/controllers/api/v1/nts/key_establishment_controller.ex
index 107954d..5a3d27f 100644
--- a/lib/chronoscope_web/controllers/api/v1/nts/key_establishment_controller.ex
+++ b/lib/chronoscope_web/controllers/api/v1/nts/key_establishment_controller.ex
@@ -8,7 +8,7 @@ defmodule ChronoscopeWeb.API.V1.NTS.KeyEstablishmentController do
   @default_port "4460"
 
   def get(conn, params) do
-    host = to_charlist(params["host"])
+    host = params["host"]
     port = String.to_integer(params["port"] || @default_port)
 
     case NTS.key_establishment(host, port) do