How IP Connect links multiple DMR Tier II Repeater Sites for Wide Area Communications
IP Connect is a digital interconnect that uses Internet Protocol (IP) to link multiple DMR Tier II repeater sites together, creating a wide-area network. With IP Connect, multiple repeater sites can be connected over a standard IP network, allowing users in different locations to talk over wide areas. IP Connect is typically deployed by organizations that have several remote locations with radio systems and they need communications between these sites. For example, a K12 school district needs to communicate between campuses, a university may have satellite campuses and the security and maintenance teams require communication between all locations, or a company may have a manufacturing facility, a warehouse logistics center, and administrative offices that need to communicate.
How IP Connect Works
The IP link can be achieved using third-party IP networks, including wide-area networks like the internet, LAN/WAN, VPNs, or microwave links. Standard network routers are used to provide IP network connectivity. The DMR protocol is transported by TCP/IP protocol at the Application layer, so IP Connect only changes the DMR transmission media without affecting the services of DMR radios and repeaters. Because the IP network carries the information that conforms to the DMR Standard, it carries all the DMR features and calling options.
Learn more about DMR Tier II Conventional Repeaters
Repeaters are typically connected to the IP network via Ethernet ports on the repeaters. The IP network required bandwidth is calculated on the amount of data transferred by one repeater. A DMR repeater with two time slots has a data rate of about 70Kbps, including digital data and GPS data. Multiply that data rate by the number of repeaters in the system for the total required IP network pipe bandwidth. Based on this, a 100Mbps data rate can accommodate about a dozen repeaters.
Carrier-grade Ethernet services are recommended with guaranteed performance to minimize the delay and jitter and dropped packets that can impact the transmission delay. Typically, an organization’s IT manager will set up the network connectivity through a third-party service provider.
The network security is guaranteed by a set of security mechanisms: data encryption, authorization code for registration, application layer protocol compliance and communication protocol command encryption. To connect to a public network, it is recommended to use a firewall.
IP Connect uses Tier II repeaters with the IP Connect license applied, along with a router to extend the DMR protocol from one repeater to many repeaters over the IP network. The local repeater communications are heard at the remote repeater site in real time, as if you were operating from there.
In this example application diagram, and organization has two different sites and requires radio communications to all users at both sites. The repeaters are connected to routers that provide connectivity to the IP network that links both sites. If someone needs to speak with a group of workers at another site, IP Connect can make this happen. Since call groups are assigned to channels, it is as easy as changing channels on a radio.
When the system is configured, call groups can be defined for the radio channels to talk over IP Connect to groups of local users at each site. Multiple channels (talk groups) can be defined for each site and for the IP Connect locations.
- Site 1 user changes channel on the radio to the Site 2 channel and the radio traffic is sent to the Site 1 repeater
- The Site 1 repeater sends that radio traffic through the IP network
- The Site 2 repeater receives that radio traffic from the IP network and sends the traffic to the appropriate users in the Site 2 channel.
- All of this works in real time as if the users were at the same location
Scalability, Flexibility, and Overlapping Coverage
IP Connect systems can link multiple repeaters at a site and can support up to 255 locations by configuring primary and secondary repeaters.
Each location can use a different frequency or DMR standard compliant radios of any manufacturer.
In addition, the IP network transport of the DMR digital data is transparent and agnostic, meaning any type of network or multiple networks of different transmission media (optical fiber, microwave, etc.) can be used to connect the repeaters in an IP Connect system.
When the coverage of IP Connect repeater locations overlap there is feature called roaming that allows the radio to switch between sites instantly and automatically. Overlapping IP Connect repeater locations must have different frequencies based on radio theory, so the radios can be programmed to switch between frequencies. This is typically for mobile radios in vehicles that drive between different repeater site locations and is like traveling with a cell phone and getting continuous connectivity from cell site to cell site.
Benefits of IP Connect
Enhanced Coverage – IP Connect is perfect to add additional coverage to additional repeater sites, or increase coverage in poor coverage areas like large parking garages and below-ground floors.
Simple Deployments – IP Connect supports repeater site connectivity over a variety of widely available IP networks, including the internet, private wide area networks, LANs and VPNs. If the existing repeaters are already Hytera, no new hardware is needed to create this wider area radio network, simply install an IP connect license and configure the repeater.
Carries True DMR Protocol – Adding Hytera IP Connect to your repeaters carries the DMR protocol. That means your existing DMR radios, regardless of manufacturer, will work on the extended IP Connect radio system for flexible deployments without being locked into proprietary systems.
Convenient and Familiar Operation – Because the IP Connect uses DMR protocol, users do not need to learn a new radio system. Group Calls, Individual Calls, Emergency Call still work as they normally do.
Local and Wide Area Channel Programming – In a Hytera IP Connect system, Talkgroups can be programmed to call users only on the local repeater, or across the IP Connected multi-site network. This is especially handy for school districts, where each school campus can have its own local repeater communications but are always available to emergency broadcasts or any other calls that need to be heard across all campuses.
Limitations of IP Connect
IP Connect enables users at multiple repeater sites to communicate over wide areas, but no matter how many repeaters, there are only two talk channels (TDMA time slots). While the coverage area is limitless, the call capacity of an IP Connect system that links DMR Tier II repeaters is limited to a single talk channel. This is where trunking is required to expand call capacity.
IP Connect repeaters can be upgraded to Hytera XPT Pseudo Trunking to expand group calling capacity with a repeater license and some simple programming.
Summary
The IP Connect Multi-Site Radio System facilitates wide-area communications by linking multiple DMR Tier II repeater sites through Internet Protocol (IP). IP Connect leverages standard IP networks to enable seamless communication between remote locations, catering to various organizational needs such as inter-campus communication for educational institutions, satellite campus coordination for universities, or intra-site communication for businesses with multiple facilities. The system operates by transporting DMR protocol over TCP/IP, ensuring compatibility with existing DMR radios and repeaters while offering features like group calls and emergency communication. Additionally, IP Connect offers scalability, flexibility, and enhanced coverage, making it an ideal solution for organizations seeking to extend their radio network without significant hardware investment.
