Implementing a business-class voice over IP (VoIP) system for the first time or even migrating from an old VoIP solution to a new one, either path represents a significant project as well as a lot of changes to how your employees do their work. They’ll need to adjust to a new way of doing things, which is never easy, and your IT department will need to focus its efforts on new management and troubleshooting tasks. Whether you’re changing to VoIP or you’re already running a VoIP-ready network, getting the best performance requires planning, active management, and monitoring.
1. Validate your network architecture. Make sure your network infrastructure will work with your chosen VoIP system, and be prepared to make changes, possibly significant ones, in order to see best performance. Not every switch, router, firewall or security appliance will work with all VoIP providers. Sometimes you may need to reconfigure or update a device, but it’s not uncommon to find that your VoIP software simply won’t work unless you swap out some hardware. In one instance, I found that the only way a VoIP product would work was to turn off all security features in my test router. That’s the kind of thing you want to know before you drop any money.
2. Are your pipes big enough? Confirm that your network will support the call quality that VoIP requires. Just because all your link lights are green doesn’t mean your employees are having clear conversations. Having sufficient bandwidth is important but so is prioritization, which means that your infrastructure needs to be able to support Quality of Service (QoS) everywhere VoIP traffic will appear. Voice traffic is extremely sensitive to things such as packet loss and jitter, meaning that a network that will work fine for data may not work well at all for voice even though it’s not generating actual errors. Only real-world testing, preferably under additional traffic load, will provide you with call quality.
3. Plan your management strategy. Ensure that your network monitoring software will support VoIP. This means that you need to be able to see what’s happening on your network that could impact VoIP traffic, whether it’s the daily backups sucking up bandwidth or a misconfigured router that’s not handling QoS properly. If you’ve opted to deploy softphone apps on workers’ mobile devices, then you’ll also need to make sure your mobile device management (MDM) solution can help keep those apps in line. Also make sure your management tools are optimized for your VoIP strategy long-term, instead of just worrying about setup the one time. Whether you’re protecting that traffic using a QoS standard or a VLAN strategy, for example, make sure you’ve got the tools to access and tweak those measures quickly anytime you need. Fortunately, most enterprise-grade VoIP network monitoring products do handle VoIP properly, but you have to check.
4. Plan your handset deployment. Check to see that your physical infrastructure will support your VoIP plans. While some VoIP phones will let you daisy-chain your workstation, this isn’t really a good idea. Instead, you should plan on dedicated Ethernet runs to each VoIP phone. Having a dedicated switch for VoIP isn’t necessarily required, especially on smaller networks, but it’s a good idea. Besides, the VoIP switch will likely need to support Power over Ethernet (PoE) unless you plan to run electrical power for every phone.
5. Check with your ISP. Call your internet service provider (ISP), and confirm that your broadband provider will support VoIP and prioritization. The internet at large doesn’t support QoS, which is one reason to keep your voice traffic away from the internet as much as possible. This may require leasing a dedicated line, which is probably a good idea considering that voice communications are about as mission-critical as it gets.
6. Engage a second broadband provider. You can’t afford to be cut off if your primary broadband provider has a problem such as a distributed denial-of-service (DDoS) attack. Yes, ISPs have become much more resilient to outages in the past 10 years, but outages still happen and if one happens to the network over which you’re running VoIP, your company’s phone stop working. Period. You need at least two providers that are independent. When things are running normally, you can load balance them. When things are not running smoothly, you still have a way to do business.
7. Consider SIP. Find a Session Initiation Protocol (SIP) solution provider that will match your needs. Some VoIP phone systems can connect directly to the good old public switched telephone network (PSTN) through a hardware interface. However, others, especially very large systems, sometimes require a provider that can connect to the PSTN using SIP. Some SIP providers use least cost routing, which means that it switches every call to the least expensive pathway available at the time the call is made. That’s certainly cheaper, but it can result in variable call quality and you probably don’t want that.
8. Plan for VoIP security. There are attacks that target VoIP traffic specifically, including call hijacking and man-in-the-middle attacks. But VoIP security goes far beyond simply protecting your network from those incursions. The National Institute of Standards and Technology (NIST) has a publication entitled, “Security Considerations for Voice Over IP Systems,” that’s a must-read for VoIP admins. Meanwhile, you’ll need to be looking at intrusion detection, virtual LANs (VLANs), and VoIP-optimized firewalls.