WiSeConnect - Network Stack Version 4.0.0 (Jan 22, 2026) - Release Notes#
Wi-Fi 6 + BLE (WiSeConnect) SDK Version 4.0.0
Simplicity SDK Version 2025.12.0
The Network Stack Software Development Kit (SDK) provides core and advanced networking features with Wi-Fi IoT cloud integration.
Click here for earlier releases.
Release Summary#
Key Features | API Changes | Bug Fixes | Chip Enablement
Key Features#
Optimized LwIP timer management for improved performance and efficiency.
Added DNS Service Discovery (DNS-SD) support via mDNS for both IPv4 and IPv6.
API Changes#
Added new MQTT API to support publish, subscribe, and manage MQTT connections directly from the network stack.
Bug Fixes#
Resolved an issue where consecutive HTTPS requests (GET/PUT/POST) could fail due to incomplete socket cleanup.
Resolved HTTP server stability issues under congested network conditions.
Resolved remote termination issues occurring during socket open/close operations in a loop.
Resolved a DTLS synchronization issue that could interrupt data transmission and reception.
Resolved TLS data transfer stability issues in 352/320k mode when power save is enabled.
Chip Enablement#
None
Key Features#
New Features | Enhancements | Removed Features | Deprecated Features
Note: See Feature Matrix for a list of any applicable APIs, examples, software variants, modes, hardware, and host interfaces applicable for each feature.
New Features#
Added DHCP support from the host for IPv4 in Dual stack mode.
Added SNI extension support for Embedded MQTT.
Added NAT/PAT feature support.
Added DNS IP address support in AP mode.
Added support for Subject Name validation during TLS connections.
Added IPv6 support in Dual Stack mode.
Added DNS-SD support over mDNS for IPv4/IPv6.
Added adaptive timer optimizations in Hosted Network stack LWIP (IPv6 ND6, DHCP, DNS, ARP, ACD, TCP, MLD6) to improve power efficiency.
Enhancements#
None
Removed Features#
None
Deprecated Features#
None
API Changes#
New APIs | Modified APIs | Removed APIs | Deprecated APIs
New APIs#
New API Signature | Deprecated API replaced by this (if any) |
|---|---|
|
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Modified APIs#
None
Removed APIs#
None
Deprecated APIs#
Deprecated API Name | Planned Removal Date |
|---|---|
2027-06 |
Bug Fixes#
Note: See the Feature Matrix section for a list of all hardware parts that work with the WiSeConnect SDK.
| ID | Issue Description | GitHub / Salesforce Reference (if any) | Affected Software Variants, Hardware, Modes, Host Interfaces |
|---|---|---|---|
| 1559294 | Resolved an issue where consecutive HTTPS requests (GET/PUT/POST) could fail due to incomplete socket cleanup. | None |
|
| 1528819 | Resolved HTTP server stability issues under congested network conditions. | None |
|
| 1535940 | Resolved remote termination issues occurring during socket open/close operations in a loop. | None |
|
| 1498368 | Resolved a DTLS synchronization issue that could interrupt data transmission and reception. | None |
|
| 1463929 | Resloved a wrap operation issue when performing TLS transmission and HMAC operations concurrently in two application threads. | None |
|
| 1454747 | Resolved firmware upgrade stability issues with proper resource cleanup. | None |
|
| 1392151 | Resolved TLS data transfer stability issues in 352/320k mode when power save is enabled. | None |
|
Chip Enablement#
None
Application Example Changes#
New Examples | Modified Examples | Removed Examples | Deprecated Examples
Note: See the Feature Matrix section for a list of all hardware parts that work with the WiSeConnect SDK.
New Examples#
| Example Name | Description | Supported Software Variants (if applicable) | Supported Modes | Supported OPNs / Boards / OPN Combinations | Supported Host Interfaces |
|---|---|---|---|---|---|
|
Paho MQTT Client over LwIP TCP See README |
Demonstrates configuring a SiWx91x device as an MQTT client using the Paho MQTT library over TCP/IP with the LwIP stack. Connecting to an MQTT broker in Wi-Fi station mode to subscribe to topics and publish messages, with optional SSL/TLS encryption support. | Standard and Lite |
|
|
SPI, UART |
|
mDNS Advertising and Discovery See README |
Demonstrates use of Multicast DNS (mDNS) to discover services and devices on the local network. Shows registration and resolution of service instances. | Standard and Lite |
|
|
SPI, UART |
Modified Examples#
None
Removed Examples#
None
Deprecated Examples#
None
Known Issues and Limitations#
| ID | Issue or Limitation Description | GitHub / Salesforce Reference (if any) | Workaround (if any) | Affected Software Variants, Hardware, Modes, Host Interfaces |
|---|---|---|---|---|
| 1427832 | Observed TLS data transfer failures in congested environments during long runs when power save is enabled. | None | None |
|
| 745282 |
Occasionally, during a TLS handshake, the device generates incorrect ECC curve parameters, causing a connection failure that results in a BBD2 error.
|
None | The error is recovered in the next attempt. |
|
| 1133422 | HTTP PUT does not support the SNI extension. | None | None |
|
| 1570754 | WebSocket connections could fail with error code -3 when connecting to certain servers. | None | None |
|
| 1571019 | mDNS discovery may fail when data transfer is active during multiple iterations. | None | None |
|
| 1571021 | mDNS start/stop with multiple services fails during multiple iterations. | None | None |
|
| 1571024 | SRV and TXT query types in mDNS discovery are currently not functioning as expected. | None | None |
|
| NA | The power-saving benefits of the hosted Network Stack LWIP may not be fully realized when IPv6 mode is enabled if the network infrastructure lacks IPv6 support. | None | None |
|
| NA | External connections to services hosted within the NAT environment are not supported. | None | None |
|
| NA | NAT/PAT is incompatible with protocols and applications that embed IP address and port number information within the payload (examples include SMTP, SNMP, and similar protocols). | None | None |
|
| NA | Network traffic translation and additional processing requirements result in increased latency and reduced throughput performance. | None | None |
|
| NA | Inbound traffic routing is not supported by the current implementation. | None | None |
|
| NA | Outbound ICMP traffic (ping requests) is restricted to a maximum payload size of 300 bytes. | None | None |
|
| N/A | TLS or DTLS connections must be initiated sequentially after the completion (success or failure) of the previous connection. | None | None |
|
| N/A | Power save with TCP/IP is not supported with the UART host interface in the non-bypass mode. | None | None |
|
| N/A | Embedded MQTT usernames are supported only up to 120 bytes. | None | None |
|
| N/A | Embedded MQTT topic lengths are supported only up to 200 bytes. | None | None |
|
| N/A | Embedded MQTT passwords are supported only up to 62 bytes. | None | None |
|
| N/A | HTTP GET URL lengths are only supported up to 2048 bytes. | None | None |
|
| N/A | More than three SSL connections are not supported. | None | None |
|
| N/A | The combined length of the mDNS service type and instance name is limited to 30 bytes maximum. | None | None |
|
| 1569000 | TCP socket send API fails with error code 33 in at_commands application on SoC with encryption enabled, preventing TCP data transmission. | None | None |
|
| 1562633 | MQTT publishing stops during BLE + Wi-Fi coexistence testing when BLE scanning is active in long run. | None | None |
|
| 1556585 | Automatic reconnection to AWS MQTT broker fails after Wi-Fi rejoin in NCP mode. If rejoin interval exceeds 10 seconds, the application hangs waiting for select_sem semaphore (timeout after 512 seconds). Manual reconnection or device reboot is required. Issue is NCP-specific and does not occur in SoC mode. | None | None |
|
| 1574418 |
Using slc generate --toolchain gcc or slc generate --with toolchain_gcc may fail with exclusivity errors due to the wiseconnect_toolchain_gcc_standard component incorrectly providing toolchain_gcc, resulting in a conflict with the Simplicity SDK toolchain_gcc component. If using those two command line options results in exclusivity errors, then you can remove them. Note that in a future WiseConnect release, you might have to reintroduce the toolchain option on the command line. Refer to future WiseConnect release notes for updates on possible behavior changes.
|
None | None |
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