The Helium Gateway application is a service designed to run on Linux-based LoRaWAN gateways.

It's intended to run alongside a typical LoRa packet forwarder and to connect via Semtech's Gateway Messaging Protocol (GWMP, using JSON v1 or v2).

In turn, the Helium Gateway application does two things:

• fetches blockchain context, such as routing tables and OUI endpoints, from a Gateway Service; this means the application does not need to maintain a full ledger of copy of the blockchain
• connects and routes packets to the appropriates OUI endpoints (ie: Helium Routers)

                                                                 +-----------+
+-----------+                       +------------+               |  Gateway  |
|           |                       |            |<--- gRPC ---->|  Service  |
|  packet   |<--- Semtech GWMP ---->|   Helium   |               +-----------+
| forwarder |       over UDP        |   Gateway  |               +-----------+
|           |                       |            |<--- gRPC ---->|  Helium   |
+-----------+                       +------------+               |  Routers  |
                                                                 +-----------+

The current gateway project forwards packets to the router via state channels and is eligible for data rewards only. Proof of coverage is not yet possible.

The project builds ipk and deb packaged releases for Linux-based LoRa gateways. These packages attempt to be self-updating to be able to track improvements to the service. Updates are delivered through the following channels which a gateway can subscribe to by a channel setting in the update section of the settings file:

• alpha - Early development releases. These will happen frequently as functionality is developed and may be unstable. Expect to need to log into your gateway to restart or manually fix your light gateway.
• beta - Pre-release candidates which are considered to be stable enough for early access. Breaking issues can still happen but should be rare.
• release - The main release channel. Updates are considered to be stable for all platforms.
• semver - This is the default channel and selects the channel based on the installed package version identifier.

NOTE: Gateways should have at least 16Mb of available application file space to handle gateway installation and updates.

This application requires a Linux-based environment for two big reasons:

• tokio: the gateway-rs application, written in Rust, depends on Tokio for its runtime. Tokio binds to Linux interfaces such as epoll and kqeueue. It is technically possible to port Tokio to another OS or RTOS (this has been done for Windows), but it would be no simple undertaking.
• curl: for fetching releases over SSL, curl is used. This was a simple way to use SSL without bloating the helium_gateway binary with additional libraries. Note that the updater may be disabled and thus this dependency may be removed.

If your supported LoRa gateway did not come with helium-gateway pre-installed, manual installation requires you to:

1. Configure the packet forwarder on the gateway to forward to the helium-gateway application. This varies per gateway but the goal is to set the packet forwarder to forward to the (default) configured helium-gateway on 127.0.0.1 at udp port 1680

2. Set up ssh acccess to the gateway. Depending on the gateway that may require going through a web interface, while others already have ssh configured.

3. scp a downloaded release package for the supported platform to the gateway. e.g.

   scp helium-gateway-<version>-<platform>.ipk <gateway>:/tmp/

4. ssh into the device and install the service using a command like:

   opkg install /tmp/helium-gateway-<version>-<platform>.ipk

   or

   dpkg --install /tmp/helium-gateway-<version>-<platform>.deb

   NOTE: Some platform have custom package installation requirements. Refer to the developer instructions for that platform on how to install a package.

   The default region of the gateway is US915, if your region is different you can set the right one in /etc/helium_gateway/settings.toml. Just add the following line at the beginning of the file:

   region = "<region>"

   Possible values are : US915| EU868 | EU433 | CN470 | CN779 | AU915 | AS923_1 | AS923_2 | AS923_3 | AS923_4 | KR920 | IN865. After updating the value you need to restart the service :

   /etc/init.d/helium_gateway restart

If this command succeeds the logs on the gateway will show the service starting and the local packet forwarder client connecting to the gateway service.

The following platforms have already been tested by Helium and our community. Our plan is to test this on all relevant hardware platforms used by the Helium Network. If your preferred platform isn't listed yet, here's how to get it added.

• Review the open issues to see if it's already in progress. If not, file an issue.
• Join the #gateway channel on Helium Discord and let us know what platform we're missing.

Note that platforms will be tested much faster if you join the development process!

Use one of the existing releases if you can, or build your own by hand using the instructions below.

If you want to support a new platform, please consider submitting a PR to get the package as part of the supported matrix of gateway platforms!

1. Install rust

   curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

2. Install cargo cross, cargo-make, and, if needed, cargo-deb. The cross command allows for cross compiling to hardware targets using docker images, while the cargo-make command is used to package up. If creating a deb package, cargo-deb is also needed.

   cargo install cross
   cargo install cargo-make
   cargo install cargo-deb

3. Build the application or package using one of the following:

   1. Build the application binary using the target triplet from the supported targets. Note the use of the --release flag to optimize the target binary for size. Debug builds may be to large to run on some targets.

      cross build --target <target> --release

      The resulting application binary is located in

      target/<target>/release/helium_gateway
      

   2. Build an application package using one of the target system profile names

      cargo make --profile <platform> pkg

      The resulting ipk or deb will be located in

      target/ipk/helium-gateway-<version>-<platform>.<ipk or deb>
      

The Helium Gateway application can be configured to suit your hardware/software environment in a variety of ways - either from the command line, using customizations to the settings.toml file or with environment variables. The following sections describe this functionality in more detail as well as more general information on how to use the application.

The Helium Gateway application is configured using TOML files for your settings. The defaults can be found in the default.toml file in this repo. You should not edit this file directly, rather you should create a settings.toml file and store it either at the default expected locaton /etc/helium_gateway/settings.toml or at a custom location of your choosing by passing the -c flag to the helium_gateway application as shown below in the general usage section.

You can customize any of the fields shown in the default.toml file. level = "info" timestamp = false

The following are the settings that can be changed and their default and optional values:

# can be any file location where you store the gateway_key.bin file
keypair = "/etc/helium_gateway/gateway_key.bin"
# can be any ip address and port combination
listen = "127.0.0.1:1680"
# possible values are : US915| EU868 | EU433 | CN470 | CN779 | AU915 | AS923_1 | AS923_2 | AS923_3 | AS923_4 | KR920 | IN865
region = "US915"

[log]
# either stdio or syslog
method = "stdio"
# possible values are: debug | info | warn
level = "info"
# either true or false
timestamp = false

[cache]
# The location of the cache store for the great gateway service
store = "/etc/helium_gateway/cache"

The default gateways / router uri and pubkey parameters can be changed, but this is only if you are using non-Helium routers. For general use with Helium you should leave these the same.

If your gateway is enabled with an ECC608 crypto chip which is set up correctly, you can configure helium_gateway to use the crypto chip for secure key storage and crypto operations.

To use in your settings.toml override the keypair setting to reflect the use of the ECC and specify the bus address and slot to use. For example:

keypair = "ecc://i2c-1:96?slot=0&network=mainnet"

will have helium_gateway use the ECC at the /dev/i2c-1 device driver location, use bus address 96 (which is hex 0x60) and slot 0 for it's crypto operations. While marking the resulting key as a mainnet key. Bus address, slot and network are all optional parameters and default to the above values (only device driver location is required such as ecc://i2c-1).

Note that the file based keypair will no longer be used once the ECC is configured for use.

See the gateway-mfr-rs repo for instructions on configuring, locking, and testing an ECC chip.

Instead of overriding paramaters in the default.toml file using a settings.toml file as described above, you can instead use environment variables. The environment variable name will be the same name as the entries in the settings file in uppercase and prefixed with "GW_". For example, following on from the above example where we change the region using region = "EU868" in the settings file, setting an environment variable of GW_REGION="EU868" will override the region setting. If the settings are in one of the lower sections such as the [log] sections then you need to also include that in the environment variable name such as GW_LOG_LEVEL.

The settings are loaded first from default.toml, then from a settings.toml file, and then from environment variables and any duplicates are overriden in the order. Therefore, please note that if you have a setting in all three locations, the environment variable will override the settings in the other two locations.

Using the Helium Gateway application is pretty simple, and the vast majority of the information you will need to use it can be gleaned by using the --help flag which provides the following output:

Helium Light Gateway

USAGE:
    helium_gateway [FLAGS] [OPTIONS] <SUBCOMMAND>

FLAGS:
        --daemon     Daemonize the application
    -h, --help       Prints help information
    -V, --version    Prints version information

OPTIONS:
    -c <config>        Configuration folder to use. default.toml will be loaded first and any custom settings in
                       settings.toml merged in [default: /etc/helium_gateway]

SUBCOMMANDS:
    add       Construct an add gateway transaction for this gateway
    help      Prints this message or the help of the given subcommand(s)
    key       Commands on gateway keys
    server    Run the gateway service

As you can see, apart from the help command, there are four core subcommands that you can pass: add, key, and server. The descriptions of what these subcommands do is shown in brief in the above help output, and are explained in more detail in the sections below.

The only option available is the config option using the -c flag. This tells the application where your configuration file is located and can be used as follows whilst passing any of the other commands such as server or add (default is /etc/helium_gateway):

./helium_gateway -c /location/of/config/folder server

Lastly you can check the version, read the help information or daemonize the application using the --version, --help and --daemon flags respectively.

As shown in the help output below, this subcommand is used to construct an add gateway transaction which can subsequently be used with the Helium Wallet application to onboard the gateway to the blockchain. More infomation on this process can be found on the docs article for Data Only Hotspots.

Construct an add gateway transaction for this gateway

USAGE:
    helium_gateway add [OPTIONS] --owner <owner> --payer <payer>

FLAGS:
    -h, --help       Prints help information
    -V, --version    Prints version information

OPTIONS:
        --mode <mode>      The staking mode for adding the light gateway [default: dataonly]
        --owner <owner>    The target owner account of this gateway
        --payer <payer>    The account that will pay account for this addition

So for example, to construct an add gateway transaction you would enter the following command at the terminal:

./helium_gateway add --owner WALLET_ADDRESS --payer WALLET_ADDRESS

You need to substitute WALLET_ADDRESS for the wallet address you will use for the owner of the hotspot and the payer of the transaction fees respectively...but please note that the --payer address must be the same as the one you will use to submit the transaction to the blockchain, or the transaction will fail.

The output of this command is a JSON object which looks like the following:

{
  "address": "11TL62V8NYvSTXmV5CZCjaucskvNR1Fdar1Pg4Hzmzk5tk2JBac",
  "fee": 65000,
  "mode": "dataonly",
  "owner": "14GWyFj9FjLHzoN3aX7Tq7PL6fEg4dfWPY8CrK8b9S5ZrcKDz6S",
  "payer": "14GWyFj9FjLHzoN3aX7Tq7PL6fEg4dfWPY8CrK8b9S5ZrcKDz6S",
  "staking fee": 1000000,
  "txn": "CrkBCiEBrlImpYLbJ0z0hw5b4g9isRyPrgbXs9X+RrJ4pJJc9MkSIQA7yIy7F+9oPYCTmDz+v782GMJ4AC+jM+VfjvUgAHflWSJGMEQCIGfugfLkXv23vJcfwPYjLlMyzYhKp+Rg8B2YKwnsDHaUAiASkdxUO4fdS33D7vyid8Tulizo9SLEL1lduyvda9YVRCohAa5SJqWC2ydM9IcOW+IPYrEcj64G17PV/kayeKSSXPTJOMCEPUDo+wM="
}

You can also pass a --mode flag followed by the hotspot type (dataonly | light | full) as shown below:

./helium_gateway add --owner WALLET_ADDRESS --payer WALLET_ADDRESS --mode light

The output of this command will be mostly the same as if you used the default dataonly however you will see that the mode has changed to "mode": "light", and the staking fee amount has changed to "staking fee": 4000000.

The txn field from the JSON object needs to be used as the input to the wallet command helium-wallet hotspot add when you subsequently want to add it to the blockchain. For example, using the above JSON object as an example, you would use the following command:

helium-wallet hotspots add CrkBCiEBrlImpYLbJ0z0hw5b4g9isRyPrgbXs9X+RrJ4pJJc9MkSIQA7yIy7F+9oPYCTmDz+v782GMJ4AC+jM+VfjvUgAHflWSJGMEQCIGfugfLkXv23vJcfwPYjLlMyzYhKp+Rg8B2YKwnsDHaUAiASkdxUO4fdS33D7vyid8Tulizo9SLEL1lduyvda9YVRCohAa5SJqWC2ydM9IcOW+IPYrEcj64G17PV/kayeKSSXPTJOMCEPUDo+wM=

This subcommand can be used to get the address and animal name of the gateway from the keys file as shown in the help output below. Note that the helium_gateway server has to be running for this command to work.

Commands on gateway keys

USAGE:
    helium_gateway key <SUBCOMMAND>

FLAGS:
    -h, --help       Prints help information
    -V, --version    Prints version information

SUBCOMMANDS:
    help    Prints this message or the help of the given subcommand(s)
    info    Commands on gateway keys

Using this is as simple as passing the following command in a terminal from wherever you installed the helium_gateway application:

./helium_gateway key info

The output of this is a JSON object containing the address and animal name of the hotspot as shown below:

{
  "address": "11TL62V8NYvSTXmV5CZCjaucskvNR1Fdar1Pg4Hzmzk5tk2JBac",
  "name": "wide-neon-kestrel"
}

The gateway server subcommand is used to start the gateway service on your device.

Run the gateway service

USAGE:
    helium_gateway server

FLAGS:
    -h, --help       Prints help information
    -V, --version    Prints version information

Running it is as simple as:

./helium_gateway server

However as discussed above you can also pass the -c option to tell the service that you are using a different location for your config files:

./helium_gateway -c /location/of/config/folder server