MeshSat connects a local mesh to other routes
MeshSat is an open-source gateway project, not a satellite constellation and not another name for Meshtastic. Its Bridge runs on Linux, including Raspberry Pi systems, and connects supported bearers such as Meshtastic, satellite, and cellular messaging. The maintainers describe routing that favors cheaper available paths. They explicitly label the project pre-release. MeshSat project
This is directly relevant to a neighborhood or remote-site experiment: one gateway can receive selected local messages and forward them over a link that the individual handhelds do not have. The handheld still needs a usable path to that gateway.
Conceptual architecture. The provider-side application may route to a dashboard, another endpoint, or another gateway. Two modems do not simply talk directly to one another in space.
Separate the components
| Component | Its job |
|---|---|
| Meshtastic radio | Receives or transmits on the local LoRa network |
| MeshSat Bridge | Applies forwarding/routing behavior on a Linux host |
| Reticulum | Networking and cryptographic packet transport used by supported paths |
| RockBLOCK 9704 | The hardware connection to Iridium IMT |
| Iridium/provider service | Satellite delivery, provisioning, and metered service |
| MeshSat Hub or another application | Provider-side routing and application integration where required |
The documented Android satellite flow passes messages through the satellite provider to MeshSat Hub. Offline operation at the field end does not mean the complete satellite path has no provider infrastructure. Satellite flow
What has been demonstrated?
The following is maintainer-reported evidence, checked October 29, 2026. We have not independently reproduced it.
| Path or feature | Published evidence | Limit for a purchasing decision |
|---|---|---|
| Bridge with Meshtastic serial | Working on reference hardware | Exact local radio/firmware still needs validation |
| Bridge with 9704 IMT | Maintainers report two-way real satellite verification in March 2026 | Does not validate every app or routing combination |
| Bridge Reticulum interoperability | Tests against upstream Python RNS/LXMF | The docs still distinguish this from real Sideband/CrossTalk client testing on a kit |
| Android with a 9704 through a node | Bench work is reported | Android documentation says no Reticulum packet through satellite yet |
| CrossTalk native 9704 interface | Documented optional implementation | Not tested by this research; verify the exact version and service setup |
Sources: Bridge evidence · Reticulum test boundaries · Android status · CrossTalk interface
Repository READMEs and documentation pages can lag one another, including their pinned interoperability-test versions. Preserve the exact commit and test record when selecting a build. Do not combine separate “works” claims into an end-to-end guarantee.
What is the RockBLOCK 9704 2B?
Ground Control's RockBLOCK 9704 board integrates an Iridium Certus 9704 modem and host interfaces. 2B is a documented board revision, rather than a second satellite network. The bare board needs a host controller, suitable power, an approved antenna arrangement, and environmental protection. It does not include a GPS receiver; GNSS passthrough supports a separate receiver. Hardware · Introduction
| Specification | Manufacturer's published value |
|---|---|
| Service | Two-way Iridium Messaging Transport (IMT) |
| Payload | 10–100,000 bytes |
| Rate | 4.8 kbps |
| Small-message latency | Typically under 10 seconds, subject to conditions and startup |
| Large message example | Around 170 seconds for 100 kB at the stated rate |
| Host connection | USB-C serial or TTL UART |
| Typical power states | Approximately 60 mW idle and 1.4 W transmitting; input/charging peaks differ |
Source: 9704 specification. These are vendor specifications, not measurements from a TBARC installation.
9603 and 9704 are different service paths
The older 9603 SBD path supports much smaller messages—typically up to 340 bytes outgoing and 270 incoming. The 9704 uses IMT with larger payloads and a different host protocol. Do not copy an SBD price-per-credit calculation or AT-command sequence into an IMT design. Ground Control supplies libraries for the 9704's JSON-based interface. Product comparison · 9704 integration
Airtime, activation, minimum charges, and provider routing must be quoted for the actual service. No current account-specific price was verified for this article. A 100 kB maximum is a technical capability, not an economical default message size.
Security and cost need deliberate routing
A gateway may translate application messages or carry encrypted packets. Those are different trust boundaries: do not promise end-to-end secrecy through a translating gateway without checking what each component decrypts. MeshSat's Reticulum documentation describes both raw and CrossTalk-framed IMT packet handling through its relay. Reticulum integration · MeshSat security
Our proposed gateway policy is to allow specific senders/destinations, cap message sizes, deduplicate retries, and enforce a daily traffic budget. Avoid sending every community beacon, position, and telemetry report over a paid link. Treat APRS/ham-radio output separately: encrypted payloads cannot simply be forwarded onto amateur RF to obtain a cheaper route. FCC rule
Where this fits at White Tanks
A concrete experimental use is a concise site-power or battery alarm delivered when terrestrial internet is unavailable. Establish a local mesh first, then bench-test the gateway, then verify actual satellite delivery and replies with the intended provider account. Test loss of sky view, a host restart, duplicate messages, and recovery before an unattended trial.
MeshSat is a promising implementation candidate for that experiment. It is not a finished personal satellite messenger or proof of emergency-service integration. The engineering question is which exact path is repeatable on your equipment, at a known cost, with maintainers able to service it.