diff --git a/Ryujinx.HLE/HOS/Services/Sockets/Nsd/IManager.cs b/Ryujinx.HLE/HOS/Services/Sockets/Nsd/IManager.cs
index c64dddf031..f58953d803 100644
--- a/Ryujinx.HLE/HOS/Services/Sockets/Nsd/IManager.cs
+++ b/Ryujinx.HLE/HOS/Services/Sockets/Nsd/IManager.cs
@@ -3,6 +3,8 @@ using Ryujinx.Cpu;
 using Ryujinx.HLE.Exceptions;
 using Ryujinx.HLE.HOS.Services.Settings;
 using Ryujinx.HLE.HOS.Services.Sockets.Nsd.Manager;
+using Ryujinx.HLE.HOS.Services.Sockets.Nsd.Types;
+using System.Runtime.InteropServices;
 using System.Text;
 
 namespace Ryujinx.HLE.HOS.Services.Sockets.Nsd
@@ -11,8 +13,8 @@ namespace Ryujinx.HLE.HOS.Services.Sockets.Nsd
     [Service("nsd:u")] // Max sessions: 20
     class IManager : IpcService
     {
-        private NsdSettings  _nsdSettings;
-        private FqdnResolver _fqdnResolver;
+        private readonly NsdSettings  _nsdSettings;
+        private readonly FqdnResolver _fqdnResolver;
 
         private bool _isInitialized = false;
 
@@ -20,12 +22,21 @@ namespace Ryujinx.HLE.HOS.Services.Sockets.Nsd
         {
             // TODO: Load nsd settings through the savedata 0x80000000000000B0 (nsdsave:/).
 
-            NxSettings.Settings.TryGetValue("nsd!test_mode", out object testMode);
+            if (!NxSettings.Settings.TryGetValue("nsd!test_mode", out object testMode))
+            {
+                // return ResultCode.InvalidSettingsValue;
+            }
+
+            if (!NxSettings.Settings.TryGetValue("nsd!environment_identifier", out object environmentIdentifier))
+            {
+                // return ResultCode.InvalidSettingsValue;
+            }
 
             _nsdSettings = new NsdSettings
             {
                 Initialized = true,
-                TestMode    = (bool)testMode
+                TestMode    = (bool)testMode,
+                Environment = (string)environmentIdentifier
             };
 
             _fqdnResolver = new FqdnResolver(_nsdSettings);
@@ -33,35 +44,33 @@ namespace Ryujinx.HLE.HOS.Services.Sockets.Nsd
             _isInitialized = true;
         }
 
+        [CommandHipc(5)] // 11.0.0+
+        // GetSettingUrl() -> buffer<unknown<0x100>, 0x16>
+        public ResultCode GetSettingUrl(ServiceCtx context)
+        {
+            throw new ServiceNotImplementedException(this, context, false);
+        }
+
         [CommandHipc(10)]
         // GetSettingName() -> buffer<unknown<0x100>, 0x16>
         public ResultCode GetSettingName(ServiceCtx context)
         {
-            (ulong outputPosition, ulong outputSize) = context.Request.GetBufferType0x22();
-
-            ResultCode result = _fqdnResolver.GetSettingName(context, out string settingName);
-
-            if (result == ResultCode.Success)
-            {
-                byte[] settingNameBuffer = Encoding.UTF8.GetBytes(settingName + '\0');
-
-                context.Memory.Write(outputPosition, settingNameBuffer);
-            }
-
-            return result;
+            throw new ServiceNotImplementedException(this, context, false);
         }
 
         [CommandHipc(11)]
-        // GetEnvironmentIdentifier() -> buffer<unknown<8>, 0x16>
+        // GetEnvironmentIdentifier() -> buffer<bytes<8> environment_identifier, 0x16>
         public ResultCode GetEnvironmentIdentifier(ServiceCtx context)
         {
             (ulong outputPosition, ulong outputSize) = context.Request.GetBufferType0x22();
 
-            ResultCode result = _fqdnResolver.GetEnvironmentIdentifier(context, out string identifier);
+            MemoryHelper.FillWithZeros(context.Memory, outputPosition, (int)outputSize);
+
+            ResultCode result = _fqdnResolver.GetEnvironmentIdentifier(out string identifier);
 
             if (result == ResultCode.Success)
             {
-                byte[] identifierBuffer = Encoding.UTF8.GetBytes(identifier + '\0');
+                byte[] identifierBuffer = Encoding.UTF8.GetBytes(identifier);
 
                 context.Memory.Write(outputPosition, identifierBuffer);
             }
@@ -122,11 +131,23 @@ namespace Ryujinx.HLE.HOS.Services.Sockets.Nsd
             throw new ServiceNotImplementedException(this, context, false);
         }
 
-        [CommandHipc(15)]
-        // Unknown(bytes<1>)
-        public ResultCode Unknown(ServiceCtx context)
+        [CommandHipc(15)] // 4.0.0+
+        // SetChangeEnvironmentIdentifierDisabled(bytes<1>)
+        public ResultCode SetChangeEnvironmentIdentifierDisabled(ServiceCtx context)
         {
-            throw new ServiceNotImplementedException(this, context, false);
+            byte disabled = context.RequestData.ReadByte();
+
+            // TODO: When sys:set service calls will be implemented
+            /*
+                if (((nn::settings::detail::GetServiceDiscoveryControlSettings() ^ disabled) & 1) != 0 )
+                {
+                    nn::settings::detail::SetServiceDiscoveryControlSettings(disabled & 1);
+                }
+            */
+
+            Logger.Stub?.PrintStub(LogClass.ServiceNsd, new { disabled });
+
+            return ResultCode.Success;
         }
 
         [CommandHipc(20)]
@@ -226,6 +247,24 @@ namespace Ryujinx.HLE.HOS.Services.Sockets.Nsd
             throw new ServiceNotImplementedException(this, context, false);
         }
 
+        [CommandHipc(51)] // 9.0.0+
+        // WriteTestParameter(buffer<?>)
+        public ResultCode WriteTestParameter(ServiceCtx context)
+        {
+            // TODO: Write test parameter through the savedata 0x80000000000000B0 (nsdsave:/test_parameter).
+
+            throw new ServiceNotImplementedException(this, context, false);
+        }
+
+        [CommandHipc(52)] // 9.0.0+
+        // ReadTestParameter() -> buffer<?>
+        public ResultCode ReadTestParameter(ServiceCtx context)
+        {
+            // TODO: Read test parameter through the savedata 0x80000000000000B0 (nsdsave:/test_parameter).
+
+            throw new ServiceNotImplementedException(this, context, false);
+        }
+
         [CommandHipc(60)]
         // ReadSaveDataFromFsForTest() -> buffer<unknown<0x12bf0>, 0x16>
         public ResultCode ReadSaveDataFromFsForTest(ServiceCtx context)
@@ -235,8 +274,7 @@ namespace Ryujinx.HLE.HOS.Services.Sockets.Nsd
                 return ResultCode.ServiceNotInitialized;
             }
 
-            // TODO: Call nn::nsd::detail::fs::ReadSaveDataWithOffset() at offset 0 to write the 
-            //       whole savedata inside the buffer.
+            // TODO: Read the savedata 0x80000000000000B0 (nsdsave:/file) and write it inside the buffer.
 
             Logger.Stub?.PrintStub(LogClass.ServiceNsd);
 
@@ -247,37 +285,113 @@ namespace Ryujinx.HLE.HOS.Services.Sockets.Nsd
         // WriteSaveDataToFsForTest(buffer<unknown<0x12bf0>, 0x15>)
         public ResultCode WriteSaveDataToFsForTest(ServiceCtx context)
         {
-            // NOTE: Stubbed in system module.
-
-            if (_isInitialized)
-            {
-                return ResultCode.NotImplemented;
-            }
-            else
+            if (!_isInitialized)
             {
                 return ResultCode.ServiceNotInitialized;
             }
+
+            // TODO: When sys:set service calls will be implemented
+            /*
+                if (nn::settings::detail::GetSettingsItemValueSize("nsd", "test_mode") != 1)
+                {
+                    return ResultCode.InvalidSettingsValue;
+                }
+            */
+
+            if (!_nsdSettings.TestMode)
+            {
+                return ResultCode.InvalidSettingsValue;
+            }
+
+            // TODO: Write the buffer inside the savedata 0x80000000000000B0 (nsdsave:/file).
+
+            Logger.Stub?.PrintStub(LogClass.ServiceNsd);
+
+            return ResultCode.Success;
         }
 
         [CommandHipc(62)]
         // DeleteSaveDataOfFsForTest()
         public ResultCode DeleteSaveDataOfFsForTest(ServiceCtx context)
         {
-            // NOTE: Stubbed in system module.
-
-            if (_isInitialized)
-            {
-                return ResultCode.NotImplemented;
-            }
-            else
+            if (!_isInitialized)
             {
                 return ResultCode.ServiceNotInitialized;
             }
+
+            // TODO: When sys:set service calls will be implemented
+            /*
+                if (nn::settings::detail::GetSettingsItemValueSize("nsd", "test_mode") != 1)
+                {
+                    return ResultCode.InvalidSettingsValue;
+                }
+            */
+
+            if (!_nsdSettings.TestMode)
+            {
+                return ResultCode.InvalidSettingsValue;
+            }
+
+            // TODO: Delete the savedata 0x80000000000000B0.
+
+            Logger.Stub?.PrintStub(LogClass.ServiceNsd);
+
+            return ResultCode.Success;
         }
 
-        [CommandHipc(63)]
+        [CommandHipc(63)] // 4.0.0+
         // IsChangeEnvironmentIdentifierDisabled() -> bytes<1>
         public ResultCode IsChangeEnvironmentIdentifierDisabled(ServiceCtx context)
+        {
+            // TODO: When sys:set service calls will be implemented use nn::settings::detail::GetServiceDiscoveryControlSettings()
+
+            bool disabled = false;
+
+            context.ResponseData.Write(disabled);
+
+            Logger.Stub?.PrintStub(LogClass.ServiceNsd, new { disabled });
+
+            return ResultCode.Success;
+        }
+
+        [CommandHipc(100)] // 10.0.0+
+        // GetApplicationServerEnvironmentType() -> bytes<1>
+        public ResultCode GetApplicationServerEnvironmentType(ServiceCtx context)
+        {
+            // TODO: Mount the savedata 0x80000000000000B0 (nsdsave:/test_parameter) and returns the environment type stored inside if the mount succeed.
+            //       Returns ResultCode.NullOutputObject if failed.
+
+            ResultCode result = _fqdnResolver.GetEnvironmentIdentifier(out string identifier);
+
+            if (result != ResultCode.Success)
+            {
+                return result;
+            }
+
+            byte environmentType = identifier.Substring(0, 2) switch
+            {
+                "lp" => (byte)ApplicationServerEnvironmentType.Lp,
+                "sd" => (byte)ApplicationServerEnvironmentType.Sd,
+                "sp" => (byte)ApplicationServerEnvironmentType.Sp,
+                "dp" => (byte)ApplicationServerEnvironmentType.Dp,
+                _    => (byte)ApplicationServerEnvironmentType.None
+            };
+
+            context.ResponseData.Write(environmentType);
+
+            return ResultCode.Success;
+        }
+
+        [CommandHipc(101)] // 10.0.0+
+        // SetApplicationServerEnvironmentType(bytes<1>)
+        public ResultCode SetApplicationServerEnvironmentType(ServiceCtx context)
+        {
+            throw new ServiceNotImplementedException(this, context, false);
+        }
+
+        [CommandHipc(102)] // 10.0.0+
+        // DeleteApplicationServerEnvironmentType()
+        public ResultCode DeleteApplicationServerEnvironmentType(ServiceCtx context)
         {
             throw new ServiceNotImplementedException(this, context, false);
         }
diff --git a/Ryujinx.HLE/HOS/Services/Sockets/Nsd/Manager/FqdnResolver.cs b/Ryujinx.HLE/HOS/Services/Sockets/Nsd/Manager/FqdnResolver.cs
index c400c3b8a0..2e23f3fb1c 100644
--- a/Ryujinx.HLE/HOS/Services/Sockets/Nsd/Manager/FqdnResolver.cs
+++ b/Ryujinx.HLE/HOS/Services/Sockets/Nsd/Manager/FqdnResolver.cs
@@ -13,38 +13,13 @@ namespace Ryujinx.HLE.HOS.Services.Sockets.Nsd.Manager
             _nsdSettings = nsdSettings;
         }
 
-        public ResultCode GetSettingName(ServiceCtx context, out string settingName)
+        public ResultCode GetEnvironmentIdentifier(out string identifier)
         {
             if (_nsdSettings.TestMode)
             {
-                settingName = "";
+                identifier = "err";
 
-                return ResultCode.NotImplemented;
-            }
-            else
-            {
-                settingName = "";
-
-                if (true) // TODO: Determine field (struct + 0x2C)
-                {
-                    settingName = _nsdSettings.Environment;
-
-                    return ResultCode.Success;
-                }
-
-#pragma warning disable CS0162
-                return ResultCode.NullOutputObject;
-#pragma warning restore CS0162
-            }
-        }
-
-        public ResultCode GetEnvironmentIdentifier(ServiceCtx context, out string identifier)
-        {
-            if (_nsdSettings.TestMode)
-            {
-                identifier = "rre";
-
-                return ResultCode.NotImplemented;
+                return ResultCode.InvalidSettingsValue;
             }
             else
             {
@@ -56,7 +31,14 @@ namespace Ryujinx.HLE.HOS.Services.Sockets.Nsd.Manager
 
         public ResultCode Resolve(ServiceCtx context, string address, out string resolvedAddress)
         {
-            if (address != "api.sect.srv.nintendo.net" || address != "conntest.nintendowifi.net")
+            if (address == "api.sect.srv.nintendo.net"     ||
+                address == "ctest.cdn.nintendo.net"        ||
+                address == "ctest.cdn.n.nintendoswitch.cn" ||
+                address == "unknown.dummy.nintendo.net")
+            {
+                resolvedAddress = address;
+            }
+            else
             {
                 // TODO: Load Environment from the savedata.
                 address = address.Replace("%", _nsdSettings.Environment);
@@ -87,10 +69,6 @@ namespace Ryujinx.HLE.HOS.Services.Sockets.Nsd.Manager
                     _ => address,
                 };
             }
-            else
-            {
-                resolvedAddress = address;
-            }
 
             return ResultCode.Success;
         }
diff --git a/Ryujinx.HLE/HOS/Services/Sockets/Nsd/ResultCode.cs b/Ryujinx.HLE/HOS/Services/Sockets/Nsd/ResultCode.cs
index 0e636f9ae8..993fbe8af9 100644
--- a/Ryujinx.HLE/HOS/Services/Sockets/Nsd/ResultCode.cs
+++ b/Ryujinx.HLE/HOS/Services/Sockets/Nsd/ResultCode.cs
@@ -7,7 +7,7 @@ namespace Ryujinx.HLE.HOS.Services.Sockets.Nsd
 
         Success = 0,
 
-        NotImplemented         = (  1 << ErrorCodeShift) | ModuleId,
+        InvalidSettingsValue   = (  1 << ErrorCodeShift) | ModuleId,
         InvalidObject1         = (  3 << ErrorCodeShift) | ModuleId,
         InvalidObject2         = (  4 << ErrorCodeShift) | ModuleId,
         NullOutputObject       = (  5 << ErrorCodeShift) | ModuleId,
diff --git a/Ryujinx.HLE/HOS/Services/Sockets/Nsd/Types/ApplicationServerEnvironmentType.cs b/Ryujinx.HLE/HOS/Services/Sockets/Nsd/Types/ApplicationServerEnvironmentType.cs
new file mode 100644
index 0000000000..150bdab4f1
--- /dev/null
+++ b/Ryujinx.HLE/HOS/Services/Sockets/Nsd/Types/ApplicationServerEnvironmentType.cs
@@ -0,0 +1,11 @@
+namespace Ryujinx.HLE.HOS.Services.Sockets.Nsd.Types
+{
+    enum ApplicationServerEnvironmentType : byte
+    {
+        None,
+        Lp,
+        Sd,
+        Sp,
+        Dp
+    }
+}
\ No newline at end of file
diff --git a/Ryujinx.HLE/HOS/Services/Sockets/Nsd/Types/NsdSettings.cs b/Ryujinx.HLE/HOS/Services/Sockets/Nsd/Types/NsdSettings.cs
index 2b31cb1d20..0a72fa8743 100644
--- a/Ryujinx.HLE/HOS/Services/Sockets/Nsd/Types/NsdSettings.cs
+++ b/Ryujinx.HLE/HOS/Services/Sockets/Nsd/Types/NsdSettings.cs
@@ -4,6 +4,6 @@
     {
         public bool   Initialized;
         public bool   TestMode;
-        public string Environment = "lp1";  // or "dd1" if devkit.
+        public string Environment;
     }
 }
\ No newline at end of file