WARNING : Due to recent renumbering of talkgroups, the new talkgroup for Corsica is now 20820. The previous TG 20821 is left available for French department 21. The 20820 TG was previously used for emergency QSOs. Those should normally have moved to 2080.
Corsica has its own XLX755 digital multi-protocol reflector, hosted into the TKNet data center in Ajaccio.
It accepts D-Star and DMR incoming connections, and has its own AMBE transcoding server. It’s the central connection point for all the digital repeaters of the island.
It also have inter-connections with :
- Several XLX interlink peers
- D-Star France XLX933 / DCS033 (modules A, C, K, W)
- Brandmeister France (New TG 20820 to module K)
Available communication modules are :
- A : XLX international
- B : XLX France
- C : D-Star France (XLX933 C)
- D : XLX French-speaking (F, VE)
- K : Corsica (All repeaters of the island + XLX933 C + BM 20820)
- W : French Open Network (XLX933W, BM282229)
An additional gateway with our analog repeater network (Asterisk) is under development.
Dashboard is available at :
TKNet team is working on migrating the network to AMPRNet / HamNet public IP addressing. The subnet corresponding to the whole island of Corsica will be announced directly in BGP from our data centers of Ajaccio and Bastia. Two central firewalls will control traffic inside TKNet, but also from/to the outside of the world, in order to respect local regulations. The use of public IP addressing will facilitate the operation of D-Star and DMR digital repeaters, because it won’t be necessary to use dual-addressing or address translations anymore. Moreover, local announcement in BGP will ensure lower latency for VoIP flows with our D-Star and DMR partners. Our TKBox system (OpenWRT / OpenVPN) will remain unchanged, and will facilitate “Plug and Play” connections of remote sites and end-users (compared to old AMPRNet techniques such as IP-IP and modded ripd).
This project is under heavy work in our labs, with the help of many other people involved in France and in the world. Please be patient 🙂
Our high points being connected in IP, we installed an ADS-B aircraft position receiver. It receives beacons transmitted by the aircrafts on 1090 MHz, and sends them to the site FlightRadar24.com. There, it’s possible to follow positions of aircrafts in real time.
The callsign of the “radar” is F-LFKJ2. It’s installed on the high point of Coti-Chjavari, over the bay of Ajaccio
To follow aircraft traffic over Corsica :
To know more about how the system works, click here.
We choosed Asterisk as the central element of our system. Asterisk is a free and open-source software that was originally built for enterprise telephony systems. A team of developers wrote a driver to connect an analog repeater to Asterisk. It’s called app_rpt. It’s widely used in the US, where there is a national network of Asterisk analog repeaters (AllStar). But it can also be used to build standalone systems. That’s why we choosed Asterisk / app_rpt for building a radioamateur VoIP network on our island.
The system is composed of
- A central hub (TKNet-VoIP) : This is Asterisk software, running on a virtual server in the data center. The hub is the central node of the VoIP. All remote VoIP systems (VHF/UHF repeaters) connect to the hub.
- Several VHF/UHF analog repeaters : Each repeater is composed of an receiver, a transmitter, an USB sound card, and a Raspberry Pi running Linux, Asterisk and app_rpt. Each repeater can work in standalone mode, or can be connected to the hub.
- An Echolink gateway (TK5KP-R) : Internet users can connect to the TK5KP-R Echolink entry point. If it is connected to the hub, Echolink users can be heard on any repeater also connected to the hub.
Connections between Asterisk nodes are using Asterisk native protocol (IAX2) over TCP/IP on TKNet. As it is a “closed” network, traffic is never transmitted to Internet, and no Internet user can connect to it.
There are other ways to connect to TKNet-VoIP :
- Android “IaxRPT” application : This dedicated app can connect to the hub from any Android smartphone. An OpenVPN Android client (with valid authentication) is required.
- Any VoIP application : Any VoIP application (initially designed for remote access to business telephony systems) can be used from any smartphone (Android or Apple). Some succesful tests have been made using Zoiper Android app. An OpenVPN client is also required to enter TKNet.
Thys system has the advantage of using only standard protocols (IAX2, SIP). Most of the software are also free and open-source. HAM network manager has full freedom about what he can do, and how he wants to build his network. No agreement from any third-party business or group is required.
Interconnections are also being developped between Asterisk (Analog) and pure digital systems (D-Star, DMR, etc…). More to follow…
TKNet network is made of :
- Two data centers, in Ajaccio and Bastia. Those DC host various virtual servers : DNS, Firewalls, VPN gateways, WEB server, VoIP server (Asterisk, XLX), monitoring, mail, etc…
- A TCP/IP transport network using 5 GHz radio links (commercial equipment configured to work on the amateur radio bands, according to the HAM specific regulations) and VPN (“Virtual Private Network”) tunnels allowing secured communication between sites.
- Many TKBox routers on various sites. TKBox are low-cost routers flashed with open-source “OpenWRT” firmware. A TKBox connects behind any Internet box (xDSL, cable, fiber, satellite, 3G…). TKBox establishes VPN tunnels to data centers, thus allowing communication between all TKNet sites. VPNs are using OpenVPN technology. Connection is really “Plug and Play”. No specific configuration (or “port opening”) is necessary on the Internet box.
TKNet is not a public network. Accessing it is restricted to licensed Amateur Radio operators. Accessing TKNet is possible through sereval ways : a direct radio link (2.4 GHz or 5 GHz), a TKBox connected to any Internet access, or a software “OpenVPN client” to be installed on a computer (PC, Mac, Linux) or smartphone (Apple, Android).
Once connected to TKNet, you are on a private, internal network linking all sites and servers together.