Q&A

Yes. LoRa on 868 MHz respects the European duty cycle. Analogy: it can be compared to a walkie-talkie for intuition (use without an operator or subscription). In reality: it is the 868 MHz ISM band, with its own rules (airtime, power), not the same framework as PMR446 walkie-talkies.

Not for ISM 868 MHz use within legal limits. The Brussels mesh targets citizens and collectives, not only amateur radio operators.

Private messages and encrypted channels stay unreadable without the key. Only messages sent on a public channel are readable in plain text.

Community sites such as ON8AR CoreScope republish those messages when an observer has captured them within radio range. They do not display your private conversations. For privacy detail, see Protect: visible vs protected.

Your smartphone does not need 4G/5G, a SIM card, or a GPS chip to operate a MeshCore companion. It needs a working Bluetooth connection and the official app as the interface to type and read messages.

Unlike other LoRa protocols, often more demanding on hardware (why not another network in Brussels?), MeshCore prioritises accessibility:

• Apple: iOS 12.0 and up. An old iPod touch (6th generation), iPhone 5S, or obsolete iPad can become your MeshCore terminal.
• Android: very old phones disconnected from any operator work too.

Install the official app and check your platform listing directly for device compatibility:

• iOS: MeshCore on the App Store
• Android: MeshCore on Google Play

Install the MeshCore app, connect a companion (BLE or USB), join a public channel such as #brussels. The Join the mesh page details companion setup; for a fixed repeater, see Build the mesh.

When no fixed repeater is in range, companions in the group can switch to client-repeater mode: each carried device temporarily relays messages and extends the group’s range while moving.

Typical cases: festival, concert, hike, march, or any group moving outside installed mesh coverage. Create a private channel for coordination and enable client-repeater mode on the group’s companions.

In Brussels, the active community and documented settings target MeshCore: separate companion and repeater roles, regional filtering in preparation, coordination within the Belgian community. A useful mesh assumes everyone uses the same protocol.

Meshtastic is another LoRa network. It allows message exchange, but in the city messaging is not reliable for a real conversation: once enough people take part, the network saturates and exchanges become unpredictable. In practice, Meshtastic is mostly used for telemetry (sensors, positions) and a culture of “collecting” nodes visible on a map, often unreachable by radio alone.

In rural areas Meshtastic can work better, but the number of radio hops stays limited: groups end up depending on Internet gateways (MQTT), which reduces the point of investing in local radio repeaters.

To build citizen infrastructure in Brussels, MeshCore better fits that goal: text messaging designed for the mesh, less “gadget” traffic, and a local community already oriented that way.

In Brussels, the local salon is #brussels. Elsewhere in Wallonia you may also see #liege and #namur. The most used channels evolve: for an up-to-date list, see ON8AR CoreScope or links on Resources.

The path hash is a short identifier added to paths on the mesh. On a dense mesh like Brussels, the default size (1 byte) saturates quickly and increases collision risk.

We recommend 2 bytes in the app's Network settings (label: Path hash size). This aligns your companion with mesh repeaters. For technical detail (routing, CLI modes, 1 vs 2 vs 3 bytes), see Build the mesh.

Yes, for everyday use: an advert broadcasts your public key and pseudonym so others can add you. See Join: adverts.

For maximum discretion (never advertising), the benefit remains modest: see Am I better protected if I never advert?. Before a sensitive event, a disposable identity is often more practical: Protect: multiple identities.

The mesh remembers paths: the relay sequence a message successfully took. If messages no longer arrive, try Clear Path from the contact sheet in the app (or enable the equivalent option in recommended settings). The companion will recalculate a route.

To understand path routing and multi-byte path hashes, see Build: path routing and path hash.

A room server is a fixed node that keeps recent messages for authorised people: useful when correspondents are not online at the same time. In the app, you join it like a contact, with a password. The default password is often hello; change it if you are the host.

To install and configure a room server (role, CLI, mains power), see Build: room server.

The companion's Bluetooth PIN can be changed in the app's BLE settings. Useful for securing the link between your phone and the device, especially without a built-in screen. Not required to join the mesh, but recommended if others can access your phone or space.

On a dense mesh, adverts pour in. If the app automatically adds every detected node and notifies you on each discovery, tracker memory fills quickly and alerts become unusable.

We recommend disabling automatic add of all nodes and contact-discovered notifications, then manually adding people you exchange with (via Discover, QR or public key). See Join: recommended settings.

For a wired USB repeater (not a solar roof model), like the one recommended in Join: suggested hardware, mount it outside: window, balcony or railing. It must stay permanently USB-powered.

The goal is not to provide huge network coverage, but to stay reachable at home: at the back of the flat, where companion radio waves fade before reaching your device. The relay brings messages indoors and maximises your chances of being contacted, even if the companion stays at the bottom of a bag.

For a wired repeater such as the XIAO ESP32-S3 + SX1262 kit (see Join: suggested hardware), average power in repeater mode is about 0.22 W.

Comparisons (ballpark figures): vs a charger left plugged in with no phone (~0.5–1 W depending on model), the repeater uses about ¼ to ½ of that standby draw; vs a phone charging (~10 W in practice), about 2%, roughly 1/50^th of the power. Values vary by charger and phone.

Over a year, that is on the order of 1.9 kWh (0.22 W × 24 h × 365 d): a very small impact on your bill for continuous use.

Yes, once you have done the basic setup yourself right after flashing: radio preset, name and password via the MeshCore Config Tool.

Then designate a trusted person in the community: add the repeater as a contact in the app and share the password. They can finish advanced configuration remotely (console, local settings, updates). That is how a few people already maintain dozens of relays aligned on the same parameters.

Simple convention: prefix BE-BRU- followed by a local landmark (known place, STIB/MIVB stop…). Useful for finding yourself on maps, not mandatory.

For the full BE-BRU-XXXXXXXXX-TYP-YY scheme (COR, DIS, EDG, MOB… types), see the naming guide on NodeNet.be.

MeshCore operates in the ISM band with a legal ceiling of 500 mW ERP (27 dBm).

In Flanders, the #BEmesh community often recommends 14–17 dBm: the mesh there has reached critical mass, and lower TX limits interference between neighbouring relays.

In Brussels, the mesh is still nascent: do not change transmit power at commissioning: keep the device default. Detail, timeline and commands (get tx, set tx 17…) are in Transmit power (TX).

After first commissioning, send a manual advert from the app: the network must know your repeater exists.

Then: set advert.interval 0 (no zero-hop auto-advert once known). For flood advert, choose an odd value that spreads adverts (e.g. set flood.advert.interval 47, local reference). CLI commands keep English terms (advert, flood).

On first boot or after a power loss, the internal clock is wrong. Use clock sync to align it with your smartphone.

Repeat after each reboot or firmware update if needed. On some devices the clock drifts: regular resync remains useful.

The path hash summarises each relay on a mesh path. Its size sets collision risk between nodes: 1, 2 or 3 bytes depending on expected density.

We recommend 2 bytes on repeater and companion. Figures, CLI commands and collisions: see Path routing and path hash and Join the mesh (app settings).

No. Since August 2026, #BEmesh often recommends a low value (e.g. 5) on the coast, where UK traffic saturates the channel. In Brussels, we leave the default ceiling set flood.max.unscoped 64 and region allowf *: that is the most important point so newcomers who are still unscoped stay reachable. See Regional filtering.

We also do not prescribe region denyf * (unlike some Flemish guidance).

In Europe, with the ISM band (sub-band P, ETSI) that MeshCore uses, regulation imposes a maximum duty cycle of 10%: a device may transmit only a limited fraction of the time. This setting keeps the network legal, stable and fair for everyone. Without this limit, a node transmitting continuously would be like holding down the PTT on a shared radio (e.g. with a rubber band), denying others a turn to speak.

To cut carrier traceability (IMEI, SIM), airplane mode is in practice the right measure: you stop sending those identifiers to towers (see Smartphone and metadata and Two separate identities). It does not, however, make you anonymous or untraceable in an absolute sense.

Limits mainly concern a determined adversary or a compromised phone: GPS may still receive signals, a malicious app may log activity or position offline then transmit everything when connectivity returns. Correlation between carrier logs (before/after) and radio captures remains conceivable. These scenarios go beyond routine mesh use, but are worth knowing when sensitivity is high.

If you prefer a smartphone to a standalone companion, two approaches: a hardened device (few apps, updates, no dubious profiles; see Securing your data in the field); or a phone never reconnected to the network after offline MeshCore app install via USB cable. You can also use a standalone device (see Discover).

MeshCore controls only one link in the chain between you and your correspondent. See also Technical anonymity.

No. MeshCore asks for no civil name, SIM card, or phone number. Your presence on the mesh rests on a public key and a displayed pseudonym: a radio identity separate from the one tied to your phone and carrier.

Your phone, however, can still expose your civil identity as long as it contacts cell towers. See Two separate identities.

Partly. Not advertising mainly avoids broadcasting the pseudonym ↔ public key link in a packet captured by observers and republished on tools like ON8AR CoreScope or MeshCore Internet Map (see Resources).

For that link not to be established by your transmissions, you also need strict discipline: never send an advert and communicate only on a public channel. Private messages, private channels, and room servers still associate the public key with the radio envelope, even when content is encrypted.

The benefit remains modest: harder to be found easily in aggregators, but activity (pseudonym, timestamp, channel) is still capturable within radio range. It blurs the trail, without making presence invisible.

In practice, a disposable identity (regenerate the key and adopt an obscure pseudonym for the duration of an event, then restore your everyday identity) is often simpler than permanent no-advert discipline. With a disposable identity, private channels and room servers already configured in the companion remain usable. See Multiple identities on the mesh.

No. A private channel keeps no history: you see messages only in real time, connected and in range at send time. If your device is off or off-network, the message is lost to you. Plan for the coordination consequences (Which mode for what sensitivity).

The private key does not steal itself remotely. In practice, it must have been exposed: stolen or compromised Export file, copy-paste sent to a third party, key left visible in plain text, hacked account or device, stolen USB key, or access given to someone who extracts it from your companion.

With usual habits (locked devices, never transmitting the key, encrypted backups), the risk stays limited for most users. See also Protect: back up your identity.

Yes. Export your settings (including the private key) and import them on the other companion. Never leave two companions with the same private key powered on at the same time: you will disrupt routing. Export / Import procedures: Protect: your radio identity.

Companion settings → Identity section → Import → select the Export file saved earlier. Restart the companion if the app asks, then verify that the displayed public key matches the previous one. Detail: Protect: restore your identity.

If you lose your private key, you can generate a new one: MeshCore is not tied to any civil identity. Your contacts will no longer recognise you automatically: you will need to re-add them (see Join: adverts).

Regenerating the key and changing the pseudonym also helps adopt a disposable identity for an event: export your everyday identity first, then regenerate. Without a prior Export, you lose access to the old radio identity. Workflow: Protect: multiple identities.

LoRa technology on the 868 MHz band is legal for citizen use within power and duty cycle limits. If hardware is seized, a MeshCore companion or repeater is in practice closer to a walkie-talkie from a regulatory standpoint; it is not commercial subscribed telecom equipment.

Firmware updates are not a personal security concern: they mainly bring new features and gradual network improvements.

For everyday use (companion), every 6 to 12 months is enough. As the network reaches maturity, frequent updates will be less necessary.

For a repeater operator, staying current matters more (mesh alignment, new commands): see Build the mesh and Discover: Ethics and community.