D-STAR

The system was developed in the late 1990s by the Japan Amateur Radio League and uses minimum-shift keying in its packet-based standard.

[7] In 2015, FlexRadio Systems added D-STAR support to their line of HF transceivers and receivers via a software upgrade.

Finally for middleware, Apache 2.0.59, Tomcat 5.5.20, mod_jk2 2.0.4, OpenSSL 0.9.8d, Java SE 5.0 and postgreSQL 8.2.3 are utilized, but these can be different as updates occur.

Along with the open-source tools, the Icom proprietary dsipsvd or "D-STAR IP Service Daemon" and a variety of crontab entries utilize a mixture of the local PostgreSQL and BIND servers to look up callsigns and "pcname" fields (stored in BIND) which are mapped to individual 10.x.x.x internal-only addresses for routing of both voice and data traffic between participating gateways.

During installation, the Gateway 2.0 software installation script builds most of the Web-based open-source tools from source for standardization purposes, while utilizing some of the packages of the host Linux system, thus making CentOS 5.1 the common way to deploy a system, to keep incompatibilities from occurring in both package versions and configuration.

The main differences between Gateway V1 and V2 are the addition of a relational database (PostgreSQL) for more flexibility and control of updates, versus the previous use of only BIND for "database" activities, the addition of both an administrative and end-user Web interface for registration which was previously handled via command-line commands by the Gateway V1 system administrators, dropping the requirement for static public IP addresses for gateways, and the ability of the software to use a fully qualified domain name to find and communicate with the trust server, allowing for redundancy/failover options for the trust server administrators.

Dplus software development has an active following, and features such as multiple repeater/system connections similar to the type of linking done by other popular repeater-linking systems (IRLP and EchoLink) are being worked on.

Amateur radio operators do not have access to the specification of this codec or the rights to implement it on their own without buying a licensed product.

Many advanced D-STAR features rely on internet connections although simplex, repeated and crossband gateway voice and data communications do not.

During widespread disasters that compromise commercial telecommunications infrastructure, D-STAR systems (as well as other modes that rely on the internet) may suffer outages or feature degradation that impacts operations.

Without simulating such outages during drills, it is difficult to assess the impact of or establish D-STAR service recovery procedures in the event of such failures.

As of the fall of 2011, there has been almost no discussion in the ham radio literature regarding actual drills where D-STAR systems were tested with completely failed or even intermittent telecommunications infrastructure.

Comprehensive emergency communications plans used by ARES and other such organizations should address the possibility that such systems may not function as intended during major disasters.

According to FCC rules, if the algorithm is publicly published or otherwise widely available enough that transmissions are not secret, it is considered encoding rather than encryption.

However, French regulators, in April 2010, have issued a statement that rules D-STAR illegal in France, due to the ability to create a connection to the internet with it and the proprietary nature of the codec used.

The French Amateur Radio society, DR@F - Digital Radioamateur France has an online petition against this ruling, calling for the government to allow the mode, as to ban it would deny them 'fundamental rights'.

The first non-Icom D-STAR repeater fully supporting the K5TIT G2 network and D-Plus, GB7MH, went live on 10 September 2009, in West Sussex, England.

[citation needed][1][2][3] Today a home-brewed D-STAR repeater can be built using open source software, used commercial radio equipment and a computer.

Free-Star is an experimental approach to the implementation of a vendor neutral, and open source, digital communication network for amateur radio.

The program D-PRS Interface includes a "Query" entry field that streamlines this process allowing the user to simply enter the desired command.

Supports advanced text chat, personal messaging with auto-reply and inbox, e-mail gateway and a beacon mode.

D-RATS is a D-STAR communications tool that supports text chat, TCP/IP forwarding, file transfers, and can act as an e-mail gateway.

The application was developed by Dan Smith (KK7DS) for the Washington County Amateur Radio Emergency Service in Oregon.

Voice and even CW are capable of getting a message through albeit slowly, but D-STAR can transfer documents, images, and spreadsheets.

It was in the Great Coastal Gale of 2007 the Washington County ARES group was able to test D-STAR during this series of several strong Pacific storms that interrupted conventional communication systems for up to one week.

Once the situation's communication needs became established the D*Chat messaging function was used to send small text transmissions via D-STAR simplex at distances of up to seventeen miles.

[24] An ability for amateurs to send files during this weather event would have greatly increased the capacity for ARES to help during the emergency.

The first presumed D-STAR radio including pictures and diagrams can be found at Moetronix.com's Digital Voice Transceiver Project.

This requires access to the receiver's discriminator and to the direct FM modulator of the radio, sometimes available at a 9,600 bit/s packet interface.

There are third-party decoders available, either for the protocol data and for the digital speech content, but legal conflicts with the patented AMBE vocoder may exist in some jurisdictions.