Operators need to be certain that the system they are purchasing is fully IP from the consoles, through the radio network, right up to the repeaters. For systems that are IP by design, replicating the resilience of IP networks with a peer-to-peer communications architecture, and with network management built into each component, comes naturally.
Watch out for systems using an IP Gateway to convert data from IP to a proprietary network backbone, as seen in Figure 1. The inherent complexity of retrofitting legacy circuit-switched systems adds reliability challenges, as well as complexity in design, implementation and operations. In addition, the expansion of such a system will be more difficult and require proprietary switches and equipment.
A "native" IP architecture (Figure 2) has built-in autonomy and survivability, delivering a system that is reliable, highly available and doesn't have to involve additional cost or complexity.
It would be in the best interest of any LMR professional to become proficient in the maintenance of IP networks, including switches and routers. People who are unfamiliar with IP networks will be at a significant disadvantage and potentially left behind as the industry moves to new, IP-capable LMR networks. Sticking with four-wire analog links with tone remote is not a solution for the future — the advantages are too great to ignore.
Sherman Banks is a technical sales engineering support manager for EADS Secure Networks North America with more than 20 years of wireless communications experience.