The Best Business VoIP Providers for 2021

With the pandemic moving workers from offices to their homes, extending corporate phone communications to so many new locations is a challenge, especially for smaller IT departments. Fortunately, that’s where cloud-served voice over IP (VoIP) providers can shine. With cloud VoIP (sometimes called a “cloud PBX”), you can move direct extensions to new geographical locations simply by clicking a mouse. Devices can also change with similar ease either with a software download or simply by reconfiguring call forwarding. With many of these systems also adding a wide variety of team collaboration features, cloud VoIP is probably the best pandemic investment a business can make.

Still, COVID-19 won’t last forever, so keeping in mind core VoIP criteria is important, too. That means providing voice communications for employees at their desks once they start returning to the office. VoIP systems may also need to support a call center for sales, customer service, and support; and they often need to connect with and through a host of other communications channels, such as fax machines, video conferencing, conference calling, mobile communications, wireless handsets, and text messaging. On top of that, they’re often expected to provide more advanced functionality through software, like shared meeting collaboration, voicemail to email transcription, and call recording. And lest we forget, many businesses still need a service that will connect to the public switched telephone network (PSTN).  

Because they’re working across such a multitude of channels, many of today’s phone systems are adopting the moniker of Unified Communications-as-a-Service (UCaaS). These are generally cloud-based, virtual PBXes (private branch exchanges) that include at least one, usually multiple, software clients to enhance their functionality on the web, desktop, and a variety of mobile devices. UCaaS systems have a wide variety of feature sets, though most everything is based on VoIP technology (more on that below). Even residential VoIP systems come with features that are simply impossible using a conventional telephone system.

A key attraction of VoIP is that it gives these systems the flexibility to work in a wide variety of environments ranging from analog desk phones to softphones piggy-backing on a cell phone. These systems can often also integrate all or part of their softphone clients into other back-office applications, like your customer relationship management (CRM) or help desk platforms. Simply picture the standard interface of such an app that suddenly sports a dial pad and some function buttons as a pop-up screen and you’ll have a basic idea of how this works. In addition, these cloud-based systems can have a variety of phone numbers in global locations, so that your customers can have free access to your phone at little or no charge.  

How to Choose the Right VoIP System

Before you can start considering a phone system, you need to figure out exactly how you’re going to use it, and how much of your business will be involved. You need to look at your existing phone system and decide whether you’re going to simply keep all of it and bolt some VoIP functionality on top, retain only part of it, or replace the whole thing. Frequently, a total replacement isn’t in the cards if only because some parts of your existing phone system can’t be easily changed over to softphones or even desktop VoIP handsets. For example, if you have a heavy manufacturing environment with outdoor activities, such as a steel fabrication yard or a landscaping company, your old outdoor phones may be exactly what you need. You also need to decide what features of the existing phone system are required, and what features of a new phone system you feel are necessary to carry into the future.

When planning, it’s important to include stakeholders from all the key parts of your business. Yes, this especially includes the IT staff and the data security folks since your voice calls will now be data communications. But it also needs to include folks who will be using the system to get work done, especially the work that drives revenue and engages customers. These people have invaluable insights into what’s actually needed versus what’s simply cool and new. Plus, you’ll need their input to select a phone system that will actually move your business forward, not just fit into your IT environment. For business-level users, that starts with understanding what VoIP really is.

VoIP wireless handset being used

So What Is VoIP, Exactly?

VoIP is a method of digitizing voice signals, and then sending the digital voice information over an IP network. To accomplish this, the analog voice information is encoded using software called a codec. When it comes time to change the digital signal back to analog so that it’s understandable, another codec does the job.  

For a VoIP system to work, it needs a means of routing calls between users or to the outside world. In a cloud-based system, this gets handled by a virtual PBX. That’s part of your cloud VoIP service. Whatever vendor is supplying that is also running a large PBX operation in a data center somewhere, and slicing off a little of it to dedicate to your organization in exchange for your subscription fees. You’re essentially sharing a large PBX with that provider’s other customers, but because these companies use multi-tenant segmentation, your PBX will appear dedicated to you. This engine will take care of routing calls on your VoIP network and out to others as well.

However, for many businesses there’s a need to route calls to the PSTN and other analog phones. This may mean a PSTN gateway, or even a hybrid PBX, where there’s at least a small telephone switch located at your office. Your VoIP vendor will let you know if this is necessary at the planning stage. Note that these days, a PBX looks exactly like the other servers in your data center, except with an attached means of handling local and analog phones. Many small businesses, however, are avoiding on-premises PBXes partially due to cost savings and partially because the capabilities offered by all-cloud systems are more than advanced enough for their needs. Some virtual cloud PBXes, for example, can handle PSTN connectivity without on-site hardware requirements.

How UCaaS Can Benefit Your Business

If all this is starting to sound like more trouble than it’s worth, remember that turning your PBX into a software solution means significant opportunity for flexibility and integration that you simply can’t get any other way. After all, programmers can now treat your phone like an app. Where that’s taken us is to the fast-changing UCaaS paradigm. Here, VoIP providers, like the ones we’ve reviewed, provide additional software capabilities that are all implemented and managed from a single, unified console.

While the exact features offered in any particular UCaaS solution can change radically from vendor to vendor, most include options for video conferencing, shared meeting and document collaboration tools, integrated faxing, mobile VoIP integration, and device-independent softphone clients. That last one is especially important now because it means that your employees can download an app to their personal smartphone or company laptop and that app will mirror all the functionality of their corporate phone, including responding to calls coming into your business’ phone number and their extension in particular. For folks trapped at home by the pandemic, that’s a perfect solution.

Softphones are at the heart of most UCaaS instances, and for many VoIP buyers, they’re becoming the primary use case, sometimes completely obviating the need for physical handsets. Part of that is because they work as well on mobile phones and tablets as they do on desktop PCs or laptops. For workers in call centers, softphones are often the only tool because they’re the front-end window to any CRM or help desk integration, which is nowadays a must-have for that job.

So, for example, a softphone can combine a telephone conversation with text chat and screen sharing, which means a conversation between two employees can seamlessly add more participants, handle private text chats between those participants while the call is still going on, and extend to a collaboration session in which the group shares screens, documents, and data—no prep, no reserved lines, just button clicks. In the case of a CRM integration, the system could recognize the customer’s phone number or some other identifier and automatically pull up that record for the technician or sales person answering the call. It can even alert a manager to monitor the call if it’s an especially important client.

That’s the basics of UCaaS, but the concept is constantly evolving to include more communication and collaboration technologies. Those capabilities also get tweaked to provide new benefits, sometimes general, sometimes aimed at specific verticals, like healthcare, for example. The key is integration. Voice is becoming integrated with other back-end apps, and UCaaS is making that easier. In fact, it’s become so popular that it’s seen rapid growth over the last several years as recent research from Statista bears out.  

Statista chart: UCaaS Projected Market Growth in US Through 2024

UCaaS Projected Market Growth in US Through 2024

But getting the most out of not just basic VoIP communication but all these UCaaS features, too, means understanding some of the technologies running underneath or next to VoIP. For most every VoIP installations, that means SIP.

What Is SIP?

The Session Initiation Protocol (SIP) is one of the underlying technologies that make VoIP possible. This is a text-based protocol similar to HTML. It’s the most commonly used standard for setting up and controlling phone calls in most VoIP systems. You’ll run across references to SIP in most anything you do with these kinds of phone systems, especially when you’re selecting the handset hardware you want to use.

While there are still a few other legacy protocols around, and a few non-SIP standards, such as H.232, SIP is what’s used for the vast majority of modern VoIP phone systems. The most common use you’ll see for H.232 today has been in dedicated video conferencing systems; not the general purpose services running over the web, but the proprietary systems used in smart conference room installations. SIP, meanwhile, handles phone service, video conferencing, and several other tasks just fine, which is why its use is so widespread. Where it has trouble is data security, but more on that in a bit.  

What makes SIP so popular is not only that it’s deep and flexible, but also because it was purpose-built to engage in multimedia (meaning not just audio but also video and even text) communications over TCP/IP networks. For VoIP calls, SIP can set up calls using a number of IP-related protocols, including the Stream Control Transmission Protocol (SCTP), the Transmission Control Protocol (TCP), and the User Datagram Protocol (UDP), among others.

But it can also handle other functions, including session setup (initiating a call at the target endpoint—the phone you’re calling), presence management (giving an indicator of whether a user is “available,” “away,” etc.), location management (target registration), call monitoring, and more. Despite all that capability, SIP is simple compared to other VoIP protocols primarily because it’s text-based and built on an easy request/response model that’s similar in many ways to both HTTP and SMTP. Yet, it’s still capable of handling the most complex operations performed by business-grade PBXes.  

However, while understanding the basics of VoIP and SIP is important, setting one of these systems up will require some general network skills, too. For the best quality, your network will need to meet certain minimums levels of throughput for upstream and downstream data. In addition, you’ll also need to meet a minimum latency number (that is, the time between when a signal leaves a remote computer and when your system receives it), typically measured in milliseconds. You’ll also need a business-grade connection to the Internet if that’s where your call traffic is going to go.   

Concept art depicting workers beneath multiple kinds of connections

Optimizing Your Internet Connection

Most VoIP solutions will require stable and consistent internet connectivity at all your office locations where VoIP will be used. At the very least, your business phone system must have access to a business-class internet link, so discuss these needs with your company’s internet service provider (ISP). This should be a dedicated link through a dedicated router if you expect your phone calls to sound as if they were coming from a business and not someone’s home Skype connection. At a minimum, it’s important to have a router that can create virtual LANs (VLANs) and also has the ability to encrypt your voice traffic. End-to-end VoIP security for all calls is now a necessity for any business.

For larger systems, and for systems where security is critical for things like being compliant to vertical regulatory needs, your current internet connection might not be adequate. The internet doesn’t do quality of service (QoS), and bandwidth can be unpredictable. Network congestion can ruin a conference call, and activities such as DNS hijacking can put your business and data at risk.

We all love the internet, but it’s not necessarily the safest place for your business voice communications. If you fall into this category, remember that while the internet uses the IP protocol and VoIP runs over IP, that doesn’t mean that VoIP must run over the internet. You can get all the UCaaS software benefits we’ve mentioned by running your voice network over dedicated lines. Sure, it will cost more, but it will also ensure crystal clear voice quality as well as the ability to implement much-improved data security.

Optimize Your Internal Network

In addition to making sure your internet service can handle your VoIP traffic, you also need to make sure your local area network (LAN) can handle it. What makes network management tricky with VoIP is that if you simply drop it onto your network, that traffic will get processed the same as any other traffic, meaning your shared accounting application or those 20 gigabytes worth of files your assistant just stored in the cloud.

The problem there is that VoIP traffic is much more sensitive to network bumps and potholes than most general office traffic. That translates to garbled conversations, difficulty connecting over Wi-Fi, or (worst case) dropped and lost calls. If your business is small and your network is essentially contained in one or two wireless routers, then your configuration and testing headaches might be fairly small (though still there). But for medium and larger networks, these tasks can not only be complex, they’ll also be time consuming, which translates into added cost in terms of man-hours.

Fortunately, most of the providers reviewed here have engineering staff that will contact you as part of your setup process to help your IT staffers test and optimize your network prior to deploying their solutions. That’s definitely something we recommend, even if it costs extra, but there are steps you can take now to prep your LAN for VoIP and make the deployment process that much easier.

For one, be sure to understand QoS (mentioned above). This means going beyond understanding the concept and moving to how the networking equipment in your office — or your employees’ home offices if you’re still at that stage — can actually implement QoS. Most business-grade networking hardware will be able to handle QoS in more than one way, so testing which method will handle voice traffic more smoothly in your environment is important, too.

Next, you want to understand codecs. This technology is what really gives each call its voice quality because it controls both bandwidth usage and the voice data’s compression. There are several proprietary and open source voice codecs, so know which is supported by your networking equipment. Then make sure those codecs are supported by your VoIP vendor, and then test different kinds to see what’s most efficient.

Last, you’ll want to take a close look at your current network monitoring tools. At its core, VoIP is simply a specific kind of network traffic, so in the end it’ll be these tools that allow you to see that traffic and manage it across your network. Make sure that the tools you’re using support VoIP’s needs, especially around QoS, traffic analysis, and network congestion issues.

Once you’ve engaged with a VoIP provider, their engineers will help you determine the overall service grade of your network (look at that as your network’s basic “VoIP readiness factor”) and how to tweak their service and optimize your network so VoIP can run effectively over your infrastructure.

How COVID-19 Is Impacting VoIP

The pandemic has hit most VoIP installations very hard. That’s because what we’ve discussed above has been mainly about optimizing one network, your primary office network, for VoIP traffic. Those steps mean significant work and time, both for your VoIP vendor’s engineers as well as your IT staff.

But what COVID has done is move your VoIP system off of a single internal network with one big and well managed internet connection out to dozens, hundreds, even thousands of small home routers where your home-working employees now need to use their softphone clients. Maintaining good call quality there has been one of the chief challenges faced by IT professionals in 2020, and that continues today.

The problem is maintaining control over your voice quality at so many different locations. Even if you’ve got several business-grade routers working in a bunch of branch offices, this problem is surmountable since (1) it’s usually not overly difficult to provision those branch office routers remotely, and (2) the routers at those locations were chosen by your IT staff specifically because they work well with the routers at your primary location. That’s not the case with home routers.

If you’ve still got a legacy voice system, meaning an on-site PBX with analog phones, then your only real COVID response will be call forwarding to your employees’ home phones. That may or may not be acceptable to your employees, especially since these days many of them won’t have an analog phone available, which means you’ll need to do your forwarding to a personally-owned mobile phone.

If you’ve got a VoIP system, however, then you’ve likely got one of the aforementioned softphones as part of that service, and that’s how most organizations are meeting the COVID challenge, as evidenced by a survey conducted last year by sister site, Spiceworks Ziff Davis:

COVID-19 poll conducted by Spiceworks Ziff Davis, March 2020

Softphones are perfect for the pandemic, because using one means your employees can simply boot up their laptop or mobile device, install the softphone, strap on a headset, and they’re good to go. Theoretically.

In reality, that’s when you can bump into voice quality problems. Your IT staff not only can’t control those home routers remotely, they often won’t even know their capabilities. These routers were either chosen by the employee or by the employee’s ISP, so even in a midsized company, you’re looking at hundreds of different makes and models. Some will have more advanced features, like QoS, some won’t. Those that do may also implement QoS and similar features in different ways. That makes configuring and managing them very difficult for IT personnel, but they’ll still be faced with that task because if employees run into conversation problems over their softphones, their first call will be to the IT help desk. Shunting them off to the VoIP provider, or worse, the ISP, isn’t a good idea either. It’ll likely cause employee frustration since those outfits won’t be familiar with your company and they’ll either refuse support or it’ll take a very long time.

The best solution would be to equip every voice-dependent employee with a new router that’s been selected and pre-configured by your IT staff in conjunction with your company’s VoIP provider. However, that’s not only expensive (even home routers can cost between $50 and $600 these days depending on what you’re buying), it’s also a complicated and lengthy process since different residential ISPs will need those routers configured in slightly different ways. Your IT staff will need to know which employees are using which ISPs and then configure each router appropriately if they want to achieve a plug-and-play experience for employees. And that’s all for a problem that will probably go away for many businesses in a year or less. It’s just not worth the effort or the expense.

In practice, most businesses are simply handling this on a case-by-case basis since COVID is a temporary problem. Most home networks can handle the extra load as long as the employee makes sure that other latency-sensitive traffic, like gaming or video streaming, are kept to a minimum during the hours when they need to talk. If some home routers develop problems, IT staff simply build a queue and handle those one at a time. Sometimes they’ll be able to access the router remotely with the employee’s permission, sometimes they’ll have to walk that employee through configuration steps to fix the problem. Sometimes the employee will just have to live with it unless the company springs for a new router or a higher bandwidth tier from the employee’s ISP.

Future-Proofing Your VoIP Communications

Looking beyond COVID, VoIP makes the most sense for the vast majority of SMBs, not just because subscription costs are less expensive than buying on-site PBX hardware, but also because VoIP is the only way to keep up with evolving communication trends. But with integration being at the heart of VoIP and UCaaS, you can’t make a purchasing decision here without thinking about the future. On one side, think about what you’ll need in the next five years. On the other side, consider each vendor carefully to see what they’ve done over the last half decade in terms of product development and keeping up with VoIP and UCaaS trends.

It’s also critical that you consider the impact of mergers and acquisitions on your phone system, both from your own organization’s perspective as well as your VoIP provider. Because VoIP systems turn calls into data, the whole process isn’t as plug-and-play or standards-based as the old-fashioned analog phone system might have been. Should your company merge with or purchase another, VoIP compatibility could become a significant IT issue.

Just about anything you can picture a business needing from a phone or collaboration system can be delivered by a hosted VoIP PBX solution—and generally at a more affordable price than purchasing and maintaining your own on-premises PBX. It’s just a matter of selecting the right solution for your business.

Source: PCMag. Read more about the Top Providers as well as their pros and cons here.


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