In almost every aspect of our lives, the world has migrated to a fully data-centric architecture. We conduct business over Zoom, manage logistics via IP networks, and communicate globally using Voice over IP (VoIP). The copper phone line is dead; the data network is king.
Yet, if you look inside a modern police cruiser or a fire command center, you will find a communication system fundamentally stuck in the 1990s: the Project 25 (P25) public safety walkie-talkie.
For decades, municipalities have poured billions of tax dollars into legacy P25 public safety voice systems. While these systems are rugged, they offer a capability set that is severely limited: half-duplex voice. In an era of AI, real-time video, and edge computing, our first responders are still relying on digital walkie-talkies.
Why? The answer typically comes down to reliability. But the cost of that reliability has become unsustainable, and the technology is no longer the best tool for the job.
It is time to rethink the architecture of public safety communications.
The Hidden “Infrastructure Tax”
When a city buys a P25 radio system, the handheld radios, which can cost more than $8,000 per unit, are just the tip of the iceberg: the real cost is the infrastructure required to make them work.
To support a legacy voice network, a municipality must build and maintain a sprawling network of towers, repeaters, microwave backhaul links, climate-controlled bunkers, and backup generators. Each municipality is effectively functioning as its own miniature telco operator.
Contrast that set-up with the world of commercial communications.
We are surrounded by a multi-billion-dollar 5G infrastructure built by carriers like AT&T and T-Mobile. This infrastructure offers massive bandwidth, low latency, and thanks to Public Safety programs like AT&T’s FirstNet and T-Mobile’s T-Priority, it is available to public safety agencies for a fraction of the cost, as low as $10 to $40 a month, or entirely subsidized.
So, if a police department could run their comms over 5G for $10/month instead of building a $400 million private radio network, why are they not doing so?
The “Tower Down” Fear
The hesitation to rely on commercial infrastructure is logical. Public safety professionals know when the “Big One” hits (be it, hurricane, terrorist attack, or massive grid failure), commercial cellular networks often fail, and towers lose power or become congested.
If a police officer relies purely on a cell phone, and the tower goes down, that phone becomes a paperweight, and they will not be able to communicate with an officer standing ten feet away.
P25 radios have a “Direct Mode” (simplex) allowing them to talk radio-to-radio without a tower. However, this is limited to line-of-sight range. If you are on the other side of a hill or deep inside a building, you are effectively cut off.
So, agencies are held hostage by the legacy model: paying millions for redundant infrastructure just to ensure voice connectivity during the 1% of times when 5G cellular fails.
The Solution: A Hybrid MANET Architecture
The future is not about choosing between “rugged radios” and “cheap cellular.” It is about merging them into a single, resilient communications architecture. This is where Mobile Ad Hoc Networking (MANET) changes the equation.
By utilizing the Persistent Systems Wave Relay® network – an MPU5 MANET device equipped with a PT5 (5G Modem), agencies can leverage a hybrid architecture that offers the best of both worlds:
- Blue Sky Days (99% of the time): The system utilizes Cloud Relay™, which combines MPU5 MANET connectivity with the city’s existing 5G/LTE infrastructure to build a communication fabric. Officers get crystal-clear voice plus high-speed data (video, maps, tracking) across the entire municipality for pennies on the dollar. Agencies ride the “zero-cost” infrastructure that the cellular carriers have already built.
- Grey Sky Days (Disaster Mode): When the storm hits and the 5G towers go dark, the MPU5s don’t just revert to “walkie talkies,” they form a Wave Relay® MANET. Unlike legacy P25 radios limited to single-hop simplex, MPU5s act as a self-forming mesh data network. Every radio is a repeater. Your voice and data “hop” from officer to officer, vehicle to vehicle, extending connectivity miles beyond the reach of P25 Direct Mode
The Ultimate Fail-Safe: Starlink Integration
To fully retire the need for expensive city-owned towers, mobile command centers and key vehicles can be equipped with Starlink terminals, giving Wave Relay a global backhaul immune to local power grid failures.
Even if every cell tower in the city goes down, the MPU5 network on the ground can route traffic to a command vehicle, up to the Starlink satellite, and back down to HQ via Cloud Relay. This guarantees continuous connectivity without the need for the city to maintain a single square foot of tower real estate.
This is how the U.S. military builds resilient communications: through an automated PACE (Primary, Alternative, Contingency, Emergency) plan that seamlessly adapts when links fail, ensuring continuous connectivity. Much like a smartphone that automatically transitions from Wi-Fi to 5G as you leave home, the system shifts without user intervention to maintain the connection.
The Bottom Line
We are at a crossroads. We can continue to spend tax dollars upgrading obsolete, single-purpose P25 voice infrastructure costing billions to maintain. Or we can pivot to a hybrid model: one leveraging the cheap, ubiquitous speed of 5G for daily operations, and relying on the superior, decentralized power of MANET for tactical redundancy.
It is time to stop buying radios that only do one thing and start investing in intelligent data networks that do everything.
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