Universal, Multi-protocol Digital Voice Reflector

The URF Multiprotocol Gateway Reflector Server, urfd, is part of the software system for a Digital Voice Network. The sources are published under GPL Licenses.

Introduction

This will build a new kind of digital voice reflector. A urfd supports DStar protocols (DPlus, DCS, DExtra and G3) DMR protocols (MMDVMHost, DMR+ and NXDN), M17, YSF, P25 (using IMBE) and USRP (Allstar). A key part of this is the hybrid transcoder, tcd, which is in a seperate repository. You can't interlink urfd with xlxd. This reflector can be built without a transcoder, but clients will only hear other clients using the same codec. Please note that currently, urfd only supports the tcd transcoder when run locally. As a local device, urfd and tcd uses UNIX DGRAM sockets for interprocess communications. These kernel-base sockets are signifantly faster than conventional UDP/IP sockets. It should be noted that tcd supports DVSI-3003 nad DVSI-3000 devices, which it uses for AMBE vocoding.

This build support dual-stack operation, so the server on which it's running, must have both an IPv4 and IPv6 routable address if you are going to configure a dual-stack reflector.

There are many improvements previous multi-mode reflectors:

• Nearly all std::vector containers have been replaced with more appropriate containers.
• No classes are derived from any standard containers.
• For concurancy, i.e., thread management, the standard thread (std::thread) library calls have been replaced with std::future.
• Managed memory, std::unique_ptr and std::shared_ptr, is used replacing the need for calls to new and delete.
• Your reflector can be configured with up to 26 modules, A through Z and as few as one module. For other choices, the configure modules don't have to be contigious. For example, you could configure modules A, B, C and E.
• An integraded P25 Reflector with software imbe vocoder.
• An integrated NXDN Reflector
• An inegrated USRP Reflector

Only systemd-based operating systems are supported. Debian or Ubuntu is recommended. If you want to install this on a non-systemd based OS, you are on your own. Finally, this repository is designed so that you don't have to modify any file in the repository when you build your system. Any file you need to modify to properly configure your reflector will be a file you copy from you locally cloned repo. This makes it easier to update the source code when this repository is updated. Follow the instructions below to build your transcoding URF reflector.

Usage

The packages which are described in this document are designed to install server software which is used for the D-Star network infrastructure. It requires a 24/7 internet connection which can support up to three transcoded modules and up to 23 more untranscoded modules to connect repeaters and hot-spot dongles!

• The server can build a reflector that support IPv4, IPv6 or both (dual stack).
• The public IP addresses should have a DNS record which must be published in the common host files.

Installation

Below are instructions to build a URF reflector. If you are planning on an URF reflector without a transcoder, you can help your users by naming modules with names that suggest which protocol is welcome. You name modules in the config.inc.php file mentioned below.

The transcoder is in a seperate repository, but you will build, install and monitor the transcoder and reflector from two different scripts, rconfig and radmin in this repository. You should look over the README.md file in the tcd repository to understand the transcoder.

After a clean installation of Debian make sure to run update and upgrade

sudo apt update
sudo apt upgrade

Required packages (some of these will probably already be installed)

sudo apt install git
sudo apt install apache2 php5
sudo apt install build-essential
sudo apt install nlohmann-json3-dev

Download and build the repository and

git clone https://github.com/n7tae/urfd.git
cd urfd/reflector

Create and edit your configuration files

First, move to the reflector build directory and create your configuration file:

cp ../config/* .

This will create seven files:

1. The urfd.mk file contains compile-time options for urfd. If you change the BINDIR, you'll need to update how urfd.service starts urfd.
2. The urfd.ini file contains the run-time options for urfd and will be discussed below.
3. The urfd.blacklist file defines callsigns that are blocked from linking or transmitting.
4. The urfd.whitelist file defines callsigns that are allowed to link and transmit. Both of these files support the astrisk as a wild-card. The supplied blacklist and whitelist file are empty, which will allow any callsign to link and transmit, blocking no one. Both files support a limited wildcard feature.
5. The urfd.interlink file defines possible Brandmeister and URF linking.
6. The urfd.terminal file defines operations for Icom's Terminal and Access Point mode, sometimes called G3. This protocol requires significantly higher connection resources than any other mode, so it is possible to build a URF reflector without G3 support.
7. The urfd.service file is a systemd file that will start and stop urfd. Importantly, it contains the only reference to where the urfd ini file is located. Be sure to set a fully qualified path to your urfd.ini file on the ExecStart line.

You can acutally put the blacklist, whitelist, interlink, terminal and ini file anyplace and even rename them. Just make sure your ini file and service file have the proper, fully-qualified paths. The service file and the mk file need to remain in your urfd/reflector directory.

When you are done with the configuration files and ready to start the installation process, you can return to the main repository directory:

cd ..

Build urfd

After possibly editing urfd.mk, you can build your reflector: make . Besides building urfd, this will also build two helper applications that will be discussed below.

Configuring your reflector

Use your favorite text editor to set your run-time configuration in your copy of urfd.ini.

There are only a few things that need to be specified. Most important are, the reflector callsign and the IP addresses for the IPv4 and IPv6 listen ports and a transcoder port, if there is a transcoder. Dual-stack operation is enabled by specifying both an IPv4 and IPv6 address. IPv4-only single stack can be specified by leaving the IPv6 address undefined.

You can configure any modules, from A to Z. They don't have to be contigious. If your reflector is configured with a transcoder, you can specify which configured modules will be transcoded. Up to three modules can be transcoded if you have the necessary hardware.

Three protocols, BrandMeister, G3 and USRP should be disabled if you aren't going to use them.

There are three databases needed by urfd:

1. The DMR ID database maps a DMR ID to a callsign and vis versa.
2. The NXDN ID database maps an NXDN ID to a callsign and vis versa.
3. The YSF Tx/Rx database maps a callsign to a transmit/receive RF frequencies. These databases can come from a URL or a file, or both. If you specify "both", then the file will be read after the URL.

Special USRP configuration

If configured, a USRP client is very unique. A USRP client (an AllStar node) doesn't support any connect or disconnect protocol. The USRP client simply sends and receives USRP voice packets. That means, if USRP is enabled, the client is created during initialization using the configured callsign, IP address and Tx/Rx ports.

If FilePath is defined, this should point to a text file listing special, listen-only client(s), one per line. Each line defining a read-only client contains an IP address, a port number, and a callsign. Here is an example:

1.2.3.1;34001;ALLSTR1;
1.2.3.4;34004;ALLSTR4;

If you want to create listen-only clients, but you don't need a configured read/write client, then set its Callsign to NONE.

Helper apps

There are two, very useful helper applications, inicheck and dbutil. Both apps will show you a usage message if you execuate them without any arguments.

The inicheck app will use the exact same code that urfd uses to validate your urfd.ini file. Do ./inicheck -q mrefd.ini to check your infile for errors. If you see any messages containing ERROR, that means that urfd won't start. You'll have to fix the errors described in the message(s). If you only see messages containing WARNING, urfd will start, but it may not perform as expected. You will have to decide if the warning should be fixed. If you don't see any messages, it means that your ini file is syntactly correct.

The dbutil app can be used for serveral tasks relating to the three databases that urfd uses. The usage is: ./dbutil DATABASE SOURCE ACTION INIFILE, where:

• DATABASE is "dmr", "nxdn" or "ysf"
• SOURCE is "html" or "file"
• ACTION is "parse" or "errors"
• INIFLILE is the path to the infile that defines the location of the http and file sources for these three databases. One at a time, dbutil can work with any of the three DATABASEs. It can read either the http or the file SOURCE. It can either show you the data entries that are syntactically correct or incorrect (ACTION).

Installing your system

After you have written your configutation files, you can install your system:

./radmin

You can use this interactive shell script to install and uninstall your system. This can also perform other tasks like restarting the reflector or transcoder process, or be used to view the reflector or transcoder log in real time.

Stoping and starting the services manually

sudo systemctl stop urfd # (or xrfd)
sudo systemctl stop tcd

You can start each component by replacing stop with start, or you can restart each by using restart.

Copy dashboard to /var/www

Since URF is a superset of XLX, we can still take advantage of the existing XLX infrastructure. In fact, the xml file generated by urfd reports itself as an XLX reflector. This will change at some point in time.

sudo cp -r ~/urfd/dashboard /var/www/urf     # or whatever your html server uses

Please note that your www root directory might be some place else. There is one file that needs configuration. Edit the copied files, not the ones from the repository:

• pgs/config.inc.php - At a minimum set your email address, country and comment.

DO NOT enable the "calling home" feature unless you are sure that you will not be infringing on an existing XLX or XRF reflector with the same callsign suffix. If you don't understand what this means, don't set $CallingHome['Active'] to true!

Firewall settings

URF Server requires the following ports to be open and forwarded properly for in- and outgoing network traffic. Obviously you don't need to open ports for G3, USRP and BrandMeister if they are not enabled:

TCP port    80         (http) optional TCP port 443 (https)
UDP port  8880         (DMR+ DMO mode)
UDP port 10002         (BM connection)
UDP port 10017         (URF interlinking)
UDP port 12345 - 12346 (G3 Icom Terminal presence and request port)
UDP port 17000         (M17 protocol)
UPD port 20001         (DPlus protocol)
UDP port 30001         (DExtra protocol)
UDP port 30051         (DCS protocol)
UDP port 32000         (USRP protocol)
UDP port 40000         (G3 Icom Terminal port)
UDP port 41000         (P25 port)
UDP port 41400         (NXDN port)
UDP port 42000         (YSF protocol)
UDP port 62030         (MMDVM protocol)

YSF Master Server

Pay attention, the URF Server acts as an YSF Master, which provides 26 wires-x rooms. It has nothing to do with the regular YSFReflector network, hence you don’t need to register your URF at ysfreflector.de !

To-dos

I will eventually support a remote transcoder option, so that you can, for example, run urfd in a data center, and then run the transcoder somewhere you have physical access so you can plug in your AMBE vocoders. I don't recommend this as it will add unnessary and variable latency to your reflector.

A new dashboard is on the to-do list!

Copyright

• Copyright © 2016 Jean-Luc Deltombe LX3JL and Luc Engelmann LX1IQ
• Copyright © 2022 Doug McLain AD8DP and Thomas A. Early N7TAE