====================================
Lantronix NTC_55x Software
Software Release Notes
Copyright 2026 (c) Lantronix Inc.
====================================

===============
RELEASE SUMMARY
===============
Version:      3.3.1.0R9
Release Date: Apr 09, 2026

Previous version was 3.2.1.0R10 on Feb 09, 2026

==============
RELEASE STATUS
==============
  Alpha        ( )
  Beta         ( )
  Supplemental ( )
  Production   (x)
  Test         ( )

==================
PRODUCTS SUPPORTED
==================
NTC_55x
1) ntc_551_3.3.1.0R9_root.signed.star : NTC_551
2) ntc_552_3.3.1.0R9_root.signed.star : NTC_552

===================
NEW FEATURES/TASK
===================

1) BLE Feature support via CLI (2714)
2) SDK support added to NTC-5xx platform (3075, 2953, 3081, 3037)
3) TR-369 Support for firmware upgrade, device reboot and factory reset (2978, 2950, 2926, 2922)

============
Bug Fixes
============

1) Added minimum sleep timer to avoid loop  in mqtt_connect (3048)
2) Device 4G/5G LED behaviour fixes (2870, 2868)
3) Device LED BLE behaviour fix (3043)
4) Disable SSH access and ping to NTC-552 WAN IP via GRE/OpenVPN tunnel IP when Remote Access is disabled (2886)
5) Fix for Ethernet WAN interface behaviour when SIM is inserted. (2734)
6) Fix for SMS Compose UI showing “Success” incorrectly for Airtel SIM (2864)
7) Fix relating to DDNS hostname not updating Eth WAN plubic IP after  Cellular WAN is disabled (2897)
8) Improvements to the LAN/WAN port behavior (2439)
9) LDAPS improvements (2676, 3003)
10) OpenVPN enhancements (2938, 2935, 3006, 3045, 3008)
11) OpenVPN: Remove deprecated encryption ciphers options (2975, 3010)
12) OpenVPN: Remove deprecated secrete static.key used in Openvpn P2P, not supported with AES-GCM ciphers (3020)
13) OpenVPN: Specify OpenVPN config topology to subnet (3012)
14) Percepxion Remote Device Management enhancements (2992, 3036, 2979, 2857, 3038, 2996)
15) Seemless SIM switching feature support between internal and external SIM. (2954, 3065, 3071, 3034)
16) WebUI Enhancements (2960, 2930, 2876, 2814, 2655)

================
REMOVED FEATURES
================

==========================
KNOWN LIMITATIONS & ISSUES
==========================

1) 2713: When the account is locked, the user must wait for the default duration of 2 minutes or the time specified in the configuration settings.

==========================
NOTES
==========================
1) Default Configuration (SIM1 & SIM2)
    * APN, Username, and Password fields are left blank by default.
    * APN type: none
    * PDP type: ipv4v6

2) Default CID Settings
    * CID1 is enabled by default, and the default route is configured on this CID for both SIMs.
    * For Verizon or similar SIMs, users must manually enable CID3, set the default route on it, and disable CID1.

3) Perticular-SIM Configuration
    * To modify settings for a specific SIM, switch to that SIM before making changes.

4) SIM Switching Behavior
    * If the external SIM has been removed and user want to change its configuration, turn off the option:
      “Switch to internal SIM if removable SIM is removed.”
    
5) When upgrading from version v1.2.61.0/v1.2.62.0 to v2.0.1.0 /2.0.0.0 R5  or later, the APN, username, password, and authentication type values 
   will not be retained. Only the profile names will be preserved.
   Users are advised to perform a factory reset after the upgrade.

6) Default values were added to the Periodic Ping configuration parameters.


==========================
WARNINGS
==========================