diff --git a/packages/lns_server.lua b/packages/lns_server.lua
index db1f803..967098b 100644
--- a/packages/lns_server.lua
+++ b/packages/lns_server.lua
@@ -19,6 +19,13 @@ settings.define("lns_server.require_auth", {
 })
 require_auth = settings.get("lns_server.require_auth")
 
+settings.define("lns_server.auth_group", {
+    description = "Authentication group",
+    type = "string",
+    default = "admin"
+})
+local auth_group = settings.get("lns_server.auth_group")
+
 settings.define("lns_server.auth_server", {
     description = "Authentication server",
     type = "string",
@@ -126,7 +133,11 @@ while true do
                 if errorPos then
                     log("Error: " .. auth_response)
                 else
-                    auth_passed = true
+                    if auth.check_user_in_group(auth_response, auth_group) then
+                        auth_passed = true
+                    else
+                        rednet.send(client_id, "invalid auth", "lns")
+                    end
                 end
             else
                 log("Error: Auth server not found to " .. client_id)