Whatever Happened to Voice Communications?

It’s something we generally take for granted: voice communications.  And yet, without it, most businesses will have difficulty surviving for an extended period of time.  How has this important business asset evolved over the past 30 years?  Let’s take a brief look and then focus on how you can protect this critical asset.  

Clearly, voice over IP (VoIP) technology is where the technology bar is today.  It leverages Internet technology and special protocols optimized for the unique attributes of speech.  It has evolved into another application residing within an organization’s technology infrastructure.  Its servers and various supporting devices (e.g., interactive voice response, automated attendant) sit on internal data networks, usually on different subnets so as to not interfere with data traffic.  System features are pretty much the same as those available 30 years ago.  The basic underlying technology has made VoIP pretty much ubiquitous today.  

Before VoIP took over voice communications, analog and digital switching technologies made up the bulk of voice systems. One of the big challenges was that each system had its own unique internal protocols for communicating between the primary and the station equipment (e.g., phones), as well as communicating between systems.  This made it very difficult to build large networks with different vendors providing the hardware.  Single standalone systems worked fine and were compatible with most existing network protocols.  Systems came in many sizes and configurations ranging from a few dozen phones to thousands of devices.  All was generally well in the world.  

Emergence of Internet protocols and the entire concept of the Internet suddenly made it possible for phone systems, regardless of manufacturer, to communicate with each other.  It also demonstrated that voice communications, properly equipped and configured, and using the proper protocols, could evolve into applications within a data network.  Certainly the unique station equipment is still in use, as opposed to workstations and laptop computers, but the level of sophistication in a VoIP system is so high that just about every device can communicate with another.  Add to this the dramatic evolution of wireless telecommunications, and traditional voice telecoms is increasingly challenged in the office pecking order.  It is still regularly used, but not as much as in years past, owing mostly to wireless technology.  

Another important development made possible by VoIP and the Internet is the growth of hosted voice communications systems.  Today you don’t need a separate equipment room for a phone system; it resides in a third-party data center.  These cloud phone systems offer the same feature set as traditional systems, and use the Internet as the means of connecting station equipment to the remotely hosted system.  It’s also possible to eliminate the wiring infrastructure traditionally associated with phone systems.  Just plug a VoiP phone into a data outlet, and the technology does the rest.  

Protecting Your Investment in Voice Communications

With older non-VoIP technology, you needed a few key items to ensure that a system disruption could be remediated.  One was the system database, usually on a cassette or CD.  Another was access to commercial power, and in the absence of that, batteries and backup power supplies.  It was also prudent to have backup copies of plug-in circuit boards as well as an inventory of telephone sets.  After that, if there was a disruption in the external network, you had to depend on the local telecommunications carrier for resolution.  

In today’s VoIP environment the following additional considerations must be made to ensure uninterrupted VoIP service.  

1. Quality of service (QoS) –QoS is necessary to ensure that voice traffic is processed in the network the same as it would be in a non-IP environment.  QoS issues can be exacerbated during disaster conditions, since VoIP requires a constant bit rate and low latency.  From an external perspective, a complete loss of access to the Internet means the VoIP system will be disabled until Internet access has been restored.  While the VoIP system is disabled, use cell phones as an alternative.  
2. Network congestion – If external networks, such as the Public Switched Telephone Network (PSTN) or Internet, are experiencing excessive traffic volumes, congestion can occur.  This can occur in a major disaster, such as on September 11, 2001, where major switching centers were damaged and data networks were inundated by extremely high traffic volumes.  Ask your VoIP vendor for suggestions.  
3. Firewalls and network address translation (NAT) – VoIP firewalls are generally like other firewalls, but they can protect against threats to voice traffic as well as data traffic.  Just make sure the VoIP firewall supports the two most common VoIP protocols, H.323 and Session Initialization Protocol (SIP).  Firewalls should also support network address translation (NAT).  
4. Restricted, poisoned, or unavailable DNS or DHCP – Loss of access to DNS (which resolves IP addresses) and DHCP (which issues IP addresses on the LAN) can impact call setup and user access to VoIP systems.  Be sure to ask your system vendor for its solutions.  
5. Internet connectivity – Loss of Internet access means your VoIP system will be disabled.  Address this by using alternate access arrangements to the Internet, e.g., through a diversely routed physical path to the local carrier or more than one Internet service provider (ISP). 
6. PSTN connectivity – Consider installing physically separate network access to your local carrier.  Options for this include diverse access to a SONET fiber-optic network ring with multiple switching offices on the ring and network re-routing; satellite-based access; and line-of-sight microwave transmission.  
7. User provisioning – If you use a hosted VoIP resource make sure it has backup copies of the current user database, which includes service configurations, to minimize transition time.  
8. Database protection – Protect your system database by ensuring that your equipment vendor or hosting provider has a current copy and store backup copies in a secure location.  
9. Location and path diversity – For larger and more complex systems, ensure that sufficient alternate network paths routes are available to provide diversity.  The time needed to install new paths could be weeks and possibly months following a disaster.  
10. Carrier network disaster plans – Ask your network carrier(s) to demonstrate how they plan to recover and restore their networks, including yours.  Integrate this information in your network disaster recovery plans.  
11. Vendor disaster recovery capabilities – Most VoIP equipment vendors and hosting companies have well-defined disaster recovery options to help minimize system downtime.  Service level agreements (SLAs) are advisable to ensure your system can be recovered as soon as possible.  
12. Loss of network synchronization – Data networks require synchronization to a reputable network clocking source.  Loss of synchronization, while infrequent, can totally disable your system.  Check with your equipment vendor and network provider to see how they will handle it.  
13. Cyberattack – Since your VoIP system uses the Internet it too is vulnerable to cyberattacks.  This occurs mainly in the form of distributed denial of service (DDoS) attacks which can completely disable VoIP systems.  Use the same kind of security provisions for VoIP (e.g., firewalls, intrusion detection systems) that you use for your network perimeter.  
14. Install the equipment in secure areas – On-site VoIP systems are comprised of specialized servers with modules that handle stations and network connectivity.  As they are typically installed in standard 19-inch racks, make sure backup power (UPS) and secure (locked) cabinets are provided.  If you have multiple server closets, install VoIP equipment there.  For hosted VoIP systems, you probably won’t need all of the above, but check with your prospective vendor for their guidance.  
15. Build voice communications disaster plans – Despite all the DR options available from vendors and carriers, make sure you have a DR plan in place to handle an unplanned outage.  If you have multiple locations, all using VoIP, you can redirect your service to another location.  If you have only one location, check with your equipment and network suppliers for their solutions.  And if you have a hosted solution, check to see if the vendor can help you develop a DR plan.  

Despite competition from wireless technology, voice communications still plays an important part in business today.  Protect your investment in voice technology using the guidance in this article and work closely with your vendors and network carriers.