User Manual

This article serves as a guide to setting up the Asterisk communication platform from Digium on a Keenetic router. Asterisk allows you to expand your router's capabilities with IP-based PBX (IP-PBX) features. Such a PBX can support dozens of internal extensions, providing call routing across multiple external lines, call recording, interactive voice menus, conference calls, and other features. It can be used to set up a telephone network in a small office. Connecting a Keenetic Phone Station with Keenetic Plus DECT and Keenetic Linear telephony modules installed on the same device to Asterisk is performed automatically during the installation process.

To make installing and configuring Asterisk as easy as possible, use the installer available via the link at the end of this article. It allows you to automatically install Asterisk and set up the following features:

This installer is designed to set up Asterisk on a router’s internal storage with a capacity of at least 55 MB. All necessary Asterisk software components are downloaded from the repository during the installation process.

To install Asterisk, you will need the following:

1. A Keenetic router with built-in storage. Compatible models are listed below.

MIPSel architecture: Hero (KN-1011), Titan (KN-1810), Skipper (KN-1910/1912), Hero 4G (KN-2310/KN-2311), Skipper 4G (KN-2910), Hopper (KN-3810)

MIPS architecture: Hero DSL (KN-2410), Skipper DSL (KN-2112), Hopper DSL (KN-3610)

AArch64 architecture: Peak (KN-2710), Titan (KN-1811/KN-1812), Hero (KN-1012), Hopper (KN-3811), Hopper SE (KN-3812), Hopper 4G+ (KN-2312), Hero 5G (KN-4110)

2. An Internet connection to download software components from the repository.

In addition to the above, the following is required for VoLTE calls:

3. A Quectel 4G modem with USB Audio support, compatible with the asterisk-chan-quectel channel driver. Detailed information about the driver can be found here.

4. A SIM card for making phone calls on the mobile operator’s LTE network.

5. A Mini PCI-E to USB adapter with a SIM card slot. This adapter is required to connect a 4G modem with a Mini PCI-E interface to the router’s USB port.

6. External antennas for the modem. External antennas must be connected to the modem if the modem does not have built-in antennas.

7. Keenetic Plus DECT or Keenetic Linear telephone adapter with DECT handsets or telephones connected, respectively.

KeeneticOS version 4.0.4 or later must be installed on the router with the following components:

1. SSH server;

2. Open Package support;

a. Kernel modules for filesystems support;

b. Kernel modules for USB Audio support (for VoLTE);

3. QMI interface for 5G/4G/3G USB modems (for VoLTE);

4. Keenetic Phone Station (for VoLTE and automatic SIP trunk configuration).

Preparing to install Asterisk

If you need to configure VoLTE calls, please follow these steps before installing Asterisk:

1. Connect the USB modem and the telephone adapter to the router. Run the command show usb and ensure that both devices appear in the system, as shown in the screenshot below;

2. If you are using the Keenetic Plus DECT telephone adapter, register at least one DECT handset;

3. Ensure that the Phone Station is switched on and that the DECT handsets or telephones are displayed in the system (see the Phone Station page in the web interface);

4. Make sure your router is connected to the Internet.

If you need to automatically configure SIP trunks to connect Asterisk to IP telephony providers, you must first create special telephone lines in the Keenetic Phone Station to connect to these providers and ensure that SIP registration is successful and calls are working. The name of each of these lines must contain a prefix, as shown in the screenshot below.

A prefix consists of a digit from 0 to 9 and the * symbol. During Asterisk installation, the configuration of each line with this name is used to set up a SIP trunk, and the prefix is used when creating call routing rules via this SIP trunk.

Installing Asterisk

1. On the web interface page Management > Applications, in the Storages and Devices section, select Internal storage and create a new folder within it named install;

2. Depending on the architecture of the router, download the Asterisk installer file mipsel-ast-installer.tar.gz, aarch64-ast-installer.tar.gz or mips-ast-installer.tar.gz into the install folder;

3. On the web interface page Management > OPKG, under the Basic Settings section, select the Internal storage drive. Click the Save button to apply the settings and start the Asterisk installation.

The installation and configuration of Asterisk may take around four minutes. You can monitor the progress in the router’s system log. To do this, go to the web interface page Management > Diagnostics and click Show log.

The message Asterisk installed! in the system log indicates that the Asterisk installation has been completed.

Once the installation is complete, the following settings will be configured automatically:

The screenshots below show an example of automatic configuration for the Phone Station and Asterisk.

Keenetic Phone Station:

Asterisk:

You can check the current status of Asterisk using the commands pjsip show contacts and quectel show device state quectel0. These commands are executed in the Asterisk console. For instructions on how to connect to the Asterisk console, see later in this article.

Connecting IP phones

Extensions 1000–1009 and 2000–2009 configured in Asterisk are intended for connecting IP phones. When configuring an extension on an IP phone, use the following settings:

VoLTE calls

To make an outgoing VoLTE call, dial the recipient’s number on a DECT handset or a telephone connected to the telephone adapter, then press the call button. When dialling, follow the dialling rules set by your mobile network operator.

When receiving a VoLTE call on the SIM card installed in the USB modem, all DECT handsets or telephones will ring, and their displays will show the caller’s number and the line name mobile.

Calls via SIP trunks

To make an outgoing call via an automatically configured SIP trunk, dial the subscriber’s number with the appropriate prefix. In the example above, to call 1234567 via Sky, you need to dial 1*1234567. When dialling a number, follow the dialling rules applicable to your IP telephony provider.

For an incoming call via a SIP trunk, the caller will hear a prompt to dial an extension number. They can then dial one of the extension numbers 1000–1009, 2000–2009 and call another IP phone linked to that number. In the example above, phone 2 connected to the Keenetic Linear adapter is linked to the line line1002. To call this phone, you need to dial 1002.

Test calls

To test the interaction between DECT handsets/phones, the Keenetic Phone Station and Asterisk, the following functions have been configured in this setup:

Call transfer

During a call, dial ## (Blind Transfer) or ** (Attended Transfer), then dial the number of the person to whom you wish to transfer the call.

Conferences for three or more participants

To join a conference, dial 001. Every participant who joins the conference can speak to all the other participants in the conference. When a participant joins or leaves the conference, all other participants in the conference hear the relevant notifications. The first user to join the conference receives a special notification and music until other participants join.

Additional features

After installing Entware, the following features can be automatically configured and enabled using a special script:

Conversations are recorded for external and internal calls, as well as during conferences. Audio recordings of conversations in the format PCM 8000Hz mono 128kbps are saved on a USB drive in the folder /asterisk/records.

Audio recording file names have the following format:

<caller>-<callee>_<YYMMDD>-<HHMM>.wav

where:

caller — the caller’s number;

callee — the recipient’s number;

YYMMDD — the year, month and day the call took place;

HHMM — the time (hours, minutes) the call took place.

When configuring call recording, you can enable automatic conversion of audio recordings to MP3. This will reduce the size of the audio recordings by approximately 16 times.

Voicemail works as follows: if an internal number does not answer an incoming call within one minute, the caller hears a prompt to leave a message for that user. Messages can be accessed via the number 9000. To log in, you must enter the relevant extension number 100x as both the subscriber number and the password. Voicemail passwords can be changed in the configuration file \opt\etc\asterisk\voicemail.conf.

Recorded messages are stored on a USB drive in the folder /asterisk/voicemail/.

TLS SIP transport enables SIP server authentication with certificates and the encryption of SIP messages. It guarantees a connection to a genuine SIP server and prevents malicious parties from intercepting information about external calls.

For configuring the additional features described above, run the command configure-features in the Linux console to launch the script. Then follow the on-screen instructions. For information on how to connect to the Linux console, see the end of this article.

Backing up and restoring Asterisk

You can back up your current Asterisk installation to a file on a USB drive so you can quickly restore it if necessary. To do this, run the backup command in the Linux console and follow the on-screen instructions. For information on how to connect to the Linux console, see the end of this article.

To restore a previously backed-up Asterisk installation from a file:

1. Connect a USB drive with an ext4 partition to the router;

2. Create a folder named /install in the ext4 partition on the USB drive and copy the file containing your Asterisk installation into this folder;

3. Copy the same file to the root directory of the ext4 partition on the USB drive;

4. On the web interface page Management > OPKG, under the Basic Settings section, select the ext4 partition on the USB drive and click the Save button to apply the settings and start the Asterisk installation;

5. Once the installation is complete, your Asterisk installation is running on the USB drive. To deploy it to the router’s internal storage, run the restore command in the Linux console to launch the script. Then follow the on-screen instructions. See below for details on how to connect to the Linux console;

6. Once the script has finished running, on the web interface page Management > OPKG, in the Basic Settings section, select Internal Storage and click the Save button to apply the settings and run your Asterisk installation on the internal storage.

Linux console

To connect to the Linux console, log in to the router via SSH. To do this, use the free SSH client PuTTY. When configuring the connection, use the following details:

On your first connection, confirm that the security key has been added to the PuTTY cache to continue establishing the connection. For authentication, use the username: root and password: keenetic.

After successfully logging in, we recommend changing the password using the passwd command.

Asterisk console

To connect to the Asterisk console, use the command asterisk -rvvvv in the Linux console.

Below are some useful Asterisk console commands:

dialplan reload — reload extensions.conf;

pjsip show registrations — list registered SIP peers;

pjsip show contacts — display the list of contacts;

pjsip show transports — display a list of SIP transports;

core show translation — display the transcoding table. Shows the codecs installed on the system and the time required to transcode one second of audio data from one codec to another;

pjsip show channels — information about all active SIP connections;

quectel show device state quectel0 — display the current status of the 4G USB modem;

exit — return to the Linux console.

If necessary, you can modify the Asterisk configuration, install additional modules, and set up new features. A list of all available Asterisk modules and other packages available for download and installation can be found at this link: https://bin.entware.net/aarch64-k3.10/ (AArch64)

The opkg command is used to install new modules.

Example of using the command to install the H.264 video codec: opkg install asterisk-format-h264

Detailed information on configuring Asterisk can be found in the book 'Asterisk: The Definitive Guide, 5th Edition' and in numerous online articles.

Information on the Entware project: https://forum.keenetic.com/forum/53-open-packages/