Gone are the days of pushing a button on an intercom and hoping that someone on the other side will eventually hear you. Thanks to Internet protocol-based (IP-based) technology, intercoms and paging solutions have become smarter, and now have the ability to provide instant communication to the “other side,” allowing for almost instant emergency notification in most cases. 
Use of IP intercoms are increasing, in part, because it has become more cost effective and more flexible in installations than traditional hard-wired systems. IP intercoms can be placed anywhere you have an existing IP network connection. They can instantly become campus or metropolitan communications devices connecting multiple buildings to a central command and control center. They don’t require a dedicated exchange or head-end, and the signal does not have to report to a single cabinet within a building. Instead, software is all that’s often needed to manage the endpoints. In short, switching to IP can modernize your current analog intercom and paging system.
Multi-building campuses are on the leading edge of the IP intercom trend, because IP-based systems can be added to a new or existing network infrastructure and controlled from a central location.
Colin Best, manager of security systems at Brookfield Properties in Calgary, Ontario, Canada, says that installing an intelligent intercom solution in one commercial property building has helped him to manage a large office building without adding staff.
Brookfield Properties owns, develops and manages premier office properties, including 109 properties totaling 75 million square feet in the downtown cores of New York, Boston, Washington, D.C., Los Angeles, Houston, Toronto, Calgary and Ottawa. It’s one of the largest owners of commercial real estate in North America.
One of Best’s challenges is to make sure that he can communicate to occupants and emergency services personnel in its Calgary towers during emergency situations. Specifically, he says he was concerned about how durable his intercom communication system would work in a fire, for example.  “Traditionally, we have used fireman communication phones that are a component of our fire alarm systems in order to identify and communicate with occupants in the event of evacuation,” he says. “This practice, while effective in drills, essentially ties up this form of communication by the fire department when it is needed. Often, emergency services personnel radios sometimes do not work, so they want to use the fire phones, but our tenants also use them to communicate with us. That’s not the best use of an intercom system.”
Best recently replaced an aging analog system with an intercom over IP solution (IoIP) at one of the company’s high-rise complexes. In addition to traditional communication to elevator cabs and common entrances, intercom stations were installed in the freight elevator lobbies throughout the towers as well.
Before the new intercom system was installed, “this was the first we had heard of an application of intercoms specifically for life safety,” Best notes. For increased reliability, Best and his team incorporated redundant network “loops” and backup communication wiring routes, in addition to continuous line monitoring of each intercom station. Each station self checks every 30 minutes by emitting white noise and monitors the feedback to the microphone. If the microphone does not “hear” feedback, the security control center is notified.

Migrating to IP

Hard-wired intercom systems continue to blend into the past as IP-based systems proliferate, including at Immanuel Lutheran High School and College, located in Eau Claire, Wis. The campus recently replaced its analog system with an all IP intercom solution that is spread across four buildings, delivers traditional bells to classrooms and hallways, and doubles as an emergency notification/intercom system.
“We were using an Apple 2e computer to run the software for the old system, and while it worked there were no plans to marry it with the new network and fiber connections in the academic center,” says Ross Roehl, an IT engineer on the campus. “We were looking for a more versatile system where we could customize bell schedules and emergency notifications.”
The system is essentially the control center for distributing voice and bells across the entire campus. For the security aspect, Roehl is recording messages and saving them to the system as mp3 files, which can be recalled and sent to any or all of four zones across campus. The files are also forwarded as .wav files to an Aastra SIP phone system.  This ensures that the messages are reaching everyone on campus. The BellCommander system is manufactured by AcroVista Software in Texas.
IP decoders were installed in four buildings (each building represents one zone).  The Exstreamer system, from Barix, receives and decodes the mp3/.wav files and forwards them to amplifiers or speaker systems.
Roehl can customize messages for each zone, sending one notification to the academic center and different messages to other buildings. He also builds various bell schedules for automated playback to classrooms and phones based on the day and time; and he is implementing a live paging feature where general announcements or unique, critical-situation instructions can be streamed over the entire network from BellCommander to the Exstreamers and the Aastra phone system.
“We also get our share of tornadoes in this region, and it might be necessary to send different messages to different zones so we can tell people in each building where they can move to seek shelter,” Roehl adds. “Having one message go to every zone isn’t always helpful. But now we have a digital infrastructure that translates the messages clearly.”
In another example, IP intercoms are working in a very noisy environment – a train station. The Delaware PATCO Speedline is a rapid transit system operated by the Port Authority Transit Corp. that runs between Philadelphia, Pa., and Camden County, N.J. Today, more than 38,000 people daily ride the PATCO Speedline. To increase security for its riders, PATCO installed a security intercom system with emergency call stations and additional security video along 14.2 miles of track. The new intercom system, from Stentofon/Zenitel, offers direct communication access at a push of a button to one of four central security offices within PATCO. It also provides security personnel with broader and more in-depth visuals to the entire rail system when a call is placed. It is a native IP intercom solution, so there are no adapters, and it can be expanded without additional hardware. More importantly, it offers intelligible voice audio and active noise cancellation – which manages the high noise levels on the train platforms without using specialized microphones or external devices.

How to Buy an IP Intercom Solution

  • Specify an IP intercom and paging system that incorporates true IP edge devices.
  • Ensure that your IP intercom solution works on your LAN, whether VoIP-enabled or not.
  • Choose a communication system that incorporates a built-in digital audio recorder.  
  • Select a system with operational redundancy. Check for fault detection, prevention and reliability features that allow your intercoms to transfer automatically to the next available server if the primary server is unavailable.
  • Develop project requirements that include a plan for future growth/expansion that minimizes hardware purchases.
  • Buy products that offer a software development kit (SDK) to allow integration with the rest of your building controls.

Information by Chris Coffin of Digital Acoustics