D2C support in Windows

Question

Hi Microsoft team,

This is Warren from FII team, which is the MBB module vendor for PC OEM currently (e.g., DELL/HP/LENOVO).

PC OEM is doing the feasibility study if D2C (Direct to Cell, E.g., T-Satellite service from T-Mobile & SpaceX) can be supported on Windows laptop. Please refer to the attached file for more details about DIRECT_TO_CELL_SERVICE_FEB_25.pdfD2C. For D2C support on Windows, it looks like Windows currently does not have D2C solution as Android & iOS cellular phone. Below is the information we surveyed.

• Missing System-Level Choke Switches:  iOS and Android feature kernel-level "meltdown" switches (e.g., TRANSPORT_SATELLITE on Android) that aggressively freeze background data down to bytes per second.
• The Traffic Flood Problem: Windows is fundamentally designed under the assumption of unmetered, high-capacity networks. It lacks a rigorous, non-bypassable background firewall. If a Windows OS were directly exposed to a T-Satellite link (which only splits a few Kbps per device), massive background tasks—such as Windows Update, OneDrive sync loops, and telemetry reporting—would instantly flood the narrow uplink within one second, crashing the satellite cell beam.

Here are a few questions for Windows if you can comment.

1. May I know if Microsoft Windows has plan to support D2C? If yes, what's the timeline to support D2C?
2. Does Microsoft has plan to cooperate with T-Mobile for D2C (T-Satellite)?
3. Does Microsoft has D2C PoC (Prove of Concept) plan to work with MBB chipset vendor or MBB module vendor?

Your feedback and suggestion are greatly appreciated.

BR

Warren

Answer 1

Hi Warren, you should route through your existing OEM partner manager or account team, since they coordinate with Microsoft’s Windows & Devices Partner Engineering group. The standard entry point is the Microsoft Partner Center where you can log feature requests or open technical inquiries

You can access the official portal here: https://partner.microsoft.com/en-us/dashboard/account/exp/enrollment/welcome?cloudInstance=Global&accountProgram=valueaddedreseller

Answer 2

Hi Microsoft team.

Thanks for sharing the information. Could you proivde the way how to direct engagement with Microsoft through normal partner/OEM channels to discuss roadmap, feature requests, and potential joint PoCs for D2C?

Thanks,

Warren

Answer 3

Windows currently supports mobile broadband (MBB) devices through the standardized Mobile Broadband Interface Model (MBIM) over USB and the Windows mobile broadband class driver. The platform assumes 3G/4G/5G terrestrial cellular networks and does not expose any D2C-/satellite-specific transport or policy model comparable to the Android/iOS satellite modes described.

From the available information:

1. Plan or timeline to support D2C The documentation describes the existing Windows cellular architecture (NDIS/NetAdapterCx/MBBCx, MBIM-based USB devices, mobile broadband class driver, and mobile operator integration) and power/connection management for conventional cellular radios. There is no mention of a D2C/satellite transport type, satellite-specific throttling mode, or kernel-level “meltdown”/background-freeze mechanism tailored for ultra‑low‑bandwidth satellite links. No roadmap or timeline for adding D2C support is documented.
2. Cooperation with T‑Mobile for D2C (T‑Satellite) The mobile operator hardware overview and cellular architecture describe how Windows integrates with mobile operators in general (e.g., via MBIM, device services, CSPs, COSA/MultiVariant, and the Mobile Plans service), but they do not reference T‑Mobile, T‑Satellite, or any specific D2C partnership or program.
3. D2C PoC with MBB chipset/module vendors The documentation covers:
   • Requirements for Windows‑certified mobile broadband devices (USB MBIM compliance, use of the Windows mobile broadband class driver).
   • Extension points such as Device Service Extension APIs and device services (e.g., Phonebook, SIM Toolkit, GPS) that allow operator- or IHV-specific functionality.
   • The MBBCx class extension and IHV driver model for cellular modems.
   However, there is no reference to any D2C‑specific PoC program, satellite‑link PoC, or a dedicated engagement track for D2C with MBB chipset or module vendors.

Given the above, any D2C enablement on Windows today would have to be built on top of the existing mobile broadband stack (MBIM, MBBCx, device services, CSPs, and operator provisioning) and would require direct engagement with Microsoft through normal partner/OEM channels to discuss roadmap, feature requests, and potential joint PoCs.

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References:

• Mobile Broadband
• Mobile operator hardware overview
• Cellular architecture
• Mobile broadband (MBB) power management for modern standby platforms