VoIP may solve problems of interoperability - Part 1

The basic problem is that when different first-responder organisations convene at an incident scene, their radios are incompatible because they operate over different frequencies and use different techniques.

The consequences, underscored by recent incidents, are uncoordinated responses and a fragmented chain of command that can hinder the ability to save lives, property and infrastructure.

Communications interoperability is also recognised as a vital element of effective day-to-day public safety services. Incidents ranging from major incidents to natural disasters typically require response from multiagency task forces. Members might include government agencies, private assistance groups and enterprises - all of which may use incompatible radio systems.

Public safety agencies have tried things like swapping radios, mutual-aid channels and gateways that bridge two or more radio systems. Although all of these approaches provide some benefit, none completely solves the inherent limitations of radio communications.

These limitations include a lack of standards, exclusion of people using devices other than radios, inability to communicate from outside the radio range and lack of resiliency of the radio infrastructure, such as when towers topple in high winds or fire.

An approach based on IP standards - variously called radio over IP or voice over IP - overcomes these limitations.

When radio communications travel over IP networks like any other kind of voice, video or data traffic, public safety agencies can communicate, collaborate and coordinate response using any radio system, in any location with a connection to an IP network.

Use of IP networks also enables public safety agencies to augment radio with other types of voice traffic as well as video and data, increasing situational awareness by delivering the right information to the right people at the right time and in the right format.

The inherent advantages of IP - standards, redundancy and resiliency, and scalability - are especially valuable in public safety environments.

Today’s immediate need is for radio interoperability. First responders from different jurisdictions need the ability to participate in the same talk group so that they can collaborate and better coordinate their response.

Even the public is aware of the role that the lack of radio interoperability played in response to recent disasters and every new failure raises that awareness further.

Government initiatives mitigate the problem somewhat, but not entirely. Regional and state networks are helpful, but if an incident extends or progresses across state lines, the participating agencies cannot all communicate directly - the limits of the radio ‘island’ are larger.

Similarly, radios based on the P25 standard mitigate the interoperability problem because they can communicate with older radios using a variety of frequencies and technologies.

However, at least one of any two agencies needs P25-compliant radios to communicate, a situation that requires long funding cycles for radio systems, legislation and long deployment timeframes.

Three reasons underlie this situation:

• The radio spectrum is fragmented. The FCC originally allocated portions of the low end of the frequency range to public safety. As technology improved, the FCC began assigning frequencies in other bands to alleviate congestion. Today, public safety operates in 10 different bands.
• Commercial, standards-based technologies have not been available. Historically, radio systems have been dominated by a few vendors with proprietary technology, and public safety represented a small market.
• Therefore, public safety could not take advantage of standardised or commercial off-the-shelf technologies, nor did it benefit from innovations in the broader market for communications technology and devices.
• Radio equipment has a very long life cycle and funding is infrequent. By the time an agency buys new radio systems, the new radios often are not compatible with those bought earlier by neighbouring jurisdictions.

In fact, the communications challenge in public safety transcends radio interoperability. Some members of the chain of command inevitably will be outside radio range when an incident occurs.

What if they could join the radio channel using mobile phones, landline phones, IP phones or desktop PCs? And what if an incident commander could easily patch in an expert who does not have a radio, such as another country’s expert on a contagious disease or a particular form of contamination?

Today, these steps require communicating through a dispatcher - a scenario that can delay critical decisions and introduce the possibility of misunderstandings.

Addressing the challenge requires reframing it - from radio interoperability to more general communications interoperability (Figure 1). Situational awareness improves when first responders and commanders can access:

• Video sent from surveillance cameras;
• Data sent to and from the mobile data terminals in law enforcement vehicles, which operate over push-to-talk (PTT) networks;
• Instant messages sent from computers and handheld personal digital assistants (PDAs) carried by field personnel;
• Geographic information systems;
• Hazardous materials databases;
• Data from earthquake, air quality and other environmental sensors.

Figure 1: Expanding the definition of interoperability in public safety.

The ability to deliver video and data to first responders in real time enhances situational awareness beyond that which voice alone can provide. For example, streaming video helps a field commander organise resources commensurate with the threat, such as overwhelming force for a hostage situation or coordinated fire, police and emergency medical services during a chemical spill or fire.

Today, the different forms of communications vital to decision making in public safety - radio, voice, data, and video - are isolated on their own networks.

Ideally, agencies that make an investment in radio or voice interoperability should be able to capitalise on it also for sharing data and streaming video.

Recent developments have increased the urgency of communications interoperability in public safety. For example, today it is far more likely than ever before that multiple jurisdictions will cooperate in incident response.

One reason is the need for intelligent, responsive counterterrorism. Another is the increased attention paid to protecting facility access, critical infrastructure in the public and private sector, and emergency response services.

Yet another is society’s increasing vulnerability to severe weather conditions and other weather-related disasters.

Interjurisdictional collaboration also applies to day-to-day public safety operations as well as emergency response.

Examples include the Olympic Games and other major sporting events, political and diplomatic events, and conventions. Similarly, agencies increasingly expect to collaborate during crimes that span agency jurisdictions, such as car chases and gang crimes.

Recently introduced communications technologies also exacerbate interoperability problems. When multiple agencies convene, the mix of communications devices might include:

• Traditional UHF, VHF, 700 and 800 MHz radios;
• PTT radios;
• Outdoor wireless radios using new public radio frequency allocations at 2.4 and 4.9 GHz;
• New trunking systems that conserve spectrum and establish a queue to handle demand for voice or data channels;
• PTT-over-mobile phones;
• PDAs with instant messaging capability, especially useful for relaying numerical information such as location coordinates.

In the absence of an interoperability solution, these different, incompatible communications technologies effectively isolate first responders even as they work side by side.

Public safety agencies have attempted to work around the lack of radio interoperability in the following ways:

• Swapping gear - in mutual-aid situations, some agencies equip first responders with multiple voice devices, such as two or three radios and a mobile phone. This is an effective low-cost one for small events, such as crowd control, but it is ineffective for larger events and disasters. Furthermore, if the radio infrastructure sustains damage, communications cease - and command structures crumble;
• Mutual-aid channels - national or regional mutual-aid channels are set aside for use by multiple agencies that are collaborating for incident response. Although useful, mutual-aid channels can be difficult to use because of restrictions and guidelines governing use. In addition, after first responders set their handsets to the mutual-aid channel, they cannot participate in their own agency’s operational channel during the incident;
• Relaying communication through dispatchers - if decision-makers in different agencies need to communicate through their respective dispatchers, escalating response can take longer. In addition, the inability to directly hear background noise or the urgency in the first responder’s voice can compromise situational awareness;
• Radio interoperability gateways - these tactical solutions enable personnel using two or more different radio systems to join the same channel. But they do not provide a long-term solution to communications interoperability because they do not support standard phones, they do not enable commanders to monitor situations from outside the radio range, they are costly and, by tying up multiple frequencies, they increase the likelihood that someone cannot join a channel, impeding effective response.

On to part 2 >