20 November 2016

Swyx Solutions believes IP will replace GSM as the transmission platform, and not just for voice but for video and data as well. PHOTO: SWYX SOLUTIONS

Laying voice traffic over enterprise data networks started out as a contentious proposition (in more ways than one). Its success relied on the savings that it delivered against standard time-tariffed telephone billing. But early IP telephony-adopting IT departments came in for flak as end-users moaned about flaky audio quality when they were trying to sweet-talk a customer or conduct sensitive negotiations.

The introduction of more capacious network bandwidth both inside and outside of enterprise premises remediated many of the early inhibitors to VoIP take-up, and the market now expects strong growth into the foreseeable future. That’s despite decreases in landline voice traffic, and a disinclination for businesses to bite the bullet that consumers are now gnawing on: getting rid of the hardwired phone altogether, and relying on mobile and Skype, WhatsApp, etc., for voice calls.

Most research indicates that the overall market for VoIP solutions has shown modest but consistent growth over the last two-to-three years. However, singling-out the growth characteristics of internally-managed business VoIP can be fuddled by the fact that it often forms part of a unified communications (UC) system, or is also partially being operated as part of a secure hosted service. 

Analyst IHS says that the global VoIP segment totalled $73bn in 2015 – a five per cent increase over 2014. IHS had previously forecast that the enterprise VoIP market would grow to $35bn in yearly revenues by 2018.

In its 2016 VoIP and Unified Communication Services and Subscribers report, the analyst states that the competitive landscape for business VoIP products and services has become “highly fragmented”, with PBX and UC vendors, among others, expanding into the market. Additionally, hosted PBX and UC solutions and services are being sold alongside SIP trunking as multi-siteorganisations opt for hybrid infrastructures.

VoIP’s strong suit remains cost-savings: why pay some ‘greedy’ telco for line rental and tariffed calls, when for some modest upfront investment, companies could run voice traffic over existing network assets, and channel it around with the rest of the IP data traffic? The cost-saving argument has surely proved persuasive on budget-setting boards ignorant of the knock-on issues VoIP is liable to suffer, and of the fact that, over the years, circuit-switched tariffs have come down.

Not just cheap talk 

Despite its success, there are still some corporate quarters that have for one reason or another not warmed to VoIP, and still find objection to its audio quality, technical vulnerabilities, bandwidth encroachment and security flaws.

The VoIP market can assuredly be described as ‘mature’ if the number of enterprises still migrating from legacy phone systems to VoIP is anything to go by, says Mark Lewis EVP, communications and connectivity at Interoute: “We see less need for gateways to integrate our enterprise customers’ legacy devices. Calls are increasingly VoIP end-to-end, not just in the carrier core network.”

He adds that the reason enterprises ‘stuck’ with older equipment was their sunk investment which has now been completely depreciated. “This, together with the fact that VoIP can meet and sometimes exceed the performance of circuit-switched networks (IP network resilience, for example, is higher than circuit-switched due to automatic
re-routing) means we do not see many enterprises wishing to keep their
legacy equipment.”

According to Claude Sassoulas, Europe MD at Tata Communications, what started principally with a drive to reduce phone bills has evolved into a more wholistic, advanced networked application that complements the latest UC and collaboration platforms. He says this features PSTN replacement, hosted, hybrid and cloud-based services, multimodal SIP, and integration with business SaaS applications. “In sectors that rely on contact centres, VoIP is now the heartbeat of the business.
Some enterprises still remain on the fence, sticking to traditional fixed telephony because they do not want to invest in new applications that might
soon become obsolete. The key is to opt for solutions that interoperate with legacy equipment while enabling the adoption
of the newest VoIP technologies.”

Nick Galea, CEO at 3CX, agrees VoIP is no longer just about making cheap phone calls and has become a key component in any UC solution. “The level of VoIP technological development maturity is high and is continual. Vendors are now tackling issues such as security by developing VoIP hacking-prevention tools, integrations with third-party applications such as CRM systems, and deployment on various devices.” 

More about security later. 

But in the meantime, Daisy Group believes one of the greatest benefits of IP and VoIP is its ability to expand compared to the historic TDM backplanes of conventional PABXs. “Scalability at one site is easy,” says the company’s product manager Gareth Long. “But more importantly, the seamless performance across multi-site networks is a great advantage over traditional telephony solutions.”

Bandwidth and monitoring

Regardless of assurances about the ease with which VoIP platforms can be integrated into existing networks, the process is not without its pitfalls for IT practitioners. As Lewis points out, a common challenge is to ensure that your network has the capacity to cope with the volume of VoIP calls. But he adds that because these use a predictable amount of bandwidth, the job of sizing a network is made much easier with the right monitoring tools.

Having said that, network managers still need to monitor VoIP performance on an ongoing basis, introducing yet another task to their workloads. Just because it might work satisfactorily following initial installation does not mean that performance levels will stay that way over time, as new applications crowd onto the IP infrastructure. VoIP’s latency-dependence usually means that it is the first application to be adversely affected by overly-contended circuits.  

“Some verticals, recruitment or manufacturing for instance, are embracing video as part of their communications mix,” says Lewis. “When these end-users [switch] from voice to video, it can greatly affect bandwidth usage. This is where the network manager needs to monitor the usage of the network very closely, and perhaps consider rules about which end-users can use what capabilities in order to limit the risk of network saturation.”

When it comes to VoIP, tools that enable network managers to balance the necessities of contending applications could be better, reckons James Mitchell, senior product manager at Claranet. “There are a lot of tools out there that can monitor bandwidth and give network managers information about what it is being used for – which let them know how much is being taken up by email and internet browsing, and how much is being taken up by voice traffic. That’s the easy bit.

“But [VoIP systems] owned and operated by service providers do not always provide a simple dashboard, and many network managers do not have good visibility of the core platform’s performance. Part of the problem is that there are lots of moving parts – calling clusters, failovers… It’s difficult to summarise all of that information into a meaningful dashboard, so there is a way to go here.

A little less conversation

Some industry pundits argue that the VoIP quality debate has proved something of a red herring. They believe many acute latency issues have been resolved thanks to higher bandwidth networks, and that users more accustomed to the vagaries of mobile phone audio quality have become more tolerant of landline quality fluctuations compared to a decade ago. 

For instance, Mark Russell, director of operations for UK&I at Swyx, says VoIP audio quality is less a question of maturity than “acceptance” of the technology. “The quality issues that used to exist are now non-issues, because although you need to invest in better connectivity such as fibre to the cabinet, higher bandwidth is now much more affordable.”

While many end-users in today’s workplace are of a generation that has never known anything other than digitally-handled voice call quality, this is not to suggest that VoIP audio quality problems have gone away, or that it is not as important to users as it once was.

Back in the day, an enterprise voice network was the primary communications channel with customers, suppliers and associates, says John Baldwin, product manager of UC and VoIP services at Colt. Since then, investments have been made to eliminate voice interaction. For example, in airline booking systems, even complex multipart sales can be managed without call centre assistance. Thus, so much transactional interaction has now been automated that call volumes can be reduced. 

But as Baldwin points out, the remaining voice traffic has become ever more essential for a smaller but more important selection of key tasks and situations. “The voice call may not now be the support norm but has become, by definition, ‘special’. And with that focused reduction comes an increased concern for the quality and efficiency of voice communications, and the critical reliability of the service.”

The burden of scale

For Tata, a major challenge that network managers in international organisations face is how to effectively scale IP telephony services globally to all of their offices.

“In practice, many network managers are forced to work with multiple vendors in each country to keep their telephony working,” says Sassoulas. “What makes matters more challenging is that not all local vendors are able to provide the same security and reliability standards across all offices. This puts a burden on network managers day-to-day, who have to add new numbers, take care of upgrades, negotiate pricing and, crucially, provide a consistent end-user experience for all employees regardless of location.”

Greg Zweig, director of solutions marketing at GENBAND, agrees: “In many cases, CIOs are not anxious to manage the VoIP deployment process [considering the] time and staff resources it takes to discover and manage expectations across hundreds of sites and thousands of employees.”

Zweig goes on to say that while cloud-based VoIP may offer strong appeal to SMEs, larger enterprises face a number of challenging issues due to the scope and scale of their deployments. Along with the pitfalls of scaling common user experience across multiple locations mentioned above, he identifies two other primary inhibitors that MLEs encounter when replacing traditional telephony with a cloud-based solution.

Firstly, they are likely to have thousands of handsets: “If they are TDM-based, they are connected to a separate cable plant. The simple math of replacing these devices can be cost prohibitive. The trend towards using more softphone clients (desktop and mobile) can help mitigate this expense but not eliminate it.”

Secondly, Zweig says large organisations often have multiple WAN links and/or broadband connections at different sites. “In many cases these were engineered for traditional data traffic, and may not have sufficient bandwidth or QoS to sustain VoIP traffic that is driven from the cloud. Modern ICT infrastructure manages VoIP well but many organisations have generations of infrastructure deployed that is far from modern.”

According to 3CX, perhaps the most glaring inhibitor from a network management perspective is VoIP’s reliance on electrical power and on the internet. Galea says: “If your premises suffers a power cut or the broadband connection is interrupted, your VoIP system will not work. This could be catastrophic for business. That is why a network evaluation is necessary to determine whether a current setup can deal with the demands of an IP-based phone system, as well as whether service providers are reliable.”

Of course, extra redundancy can be added in the form of additional UPSs and even satellite broadband backup. But these options are arguably really only viable for enterprises with deeper pockets.

“In terms of pitfalls, there must be recognition among network managers that voice is real-time and therefore should have priority over other applications,” says Daisy Group’s Long. “It is generally best that the network is managed and supported by a single company: this will minimise any inappropriate conflicts of interest. As regards the wide area connectivity, voice should be on a private connection to your network break out. Don’t try and run voice over the open internet. It may work. But then again it may not.”

He adds that another consistent VoIP niggle is the use of the SIP application layer gateway on routers. “SIP ALG should be disabled on the router if you are wanting to run voice services across the connection. Irritatingly, some routers default to SIP ALG if they are re-booted, so beware.”

“Game over” for VoIP

Security still continues to be a major issue for VoIP – but then again, as Long points out, security remains a big issue for all forms of data networking. “Securing VoIP platforms with session border controllers is essential, and all other forms of network protection from cyber attacks should be considered. But no more so than any other aspect of the data network.”

Insecure VoIP systems offer a great opportunity for data breaches, warns Dr. Jules Pagna Disso, head of research and innovation at Nettitude. He says VoIP systems, just like IP CCTV cameras, tend to be forgotten when companies look at their security strategy. Furthermore, he reckons VoIP vulnerabilities are still not well understood even among general IT security professionals, so it is therefore not surprising that IP telephony remains largely insecure.

“When VoIP systems are used as standalone systems – i.e., not as a unified system in conjunction with other systems – they are open to attack,” says Disso. “All that is needed for the attacker to control a phone line is its extension number and its password – which in most companies is generally set to four characters, and often the same as the extension number. In most cases when an attacker has a foothold inside the network, it’s game over for VoIP systems.”

And apart from cyber attacks, there is another problem: fraud. Citing stats from the Communications Fraud Control Association, Matt Hurst, technical director at Sonus says it is estimated that fraud alone cost the industry $38.1bn in 2015, proving that voice communications systems remain a lucrative target for hackers and thieves. “Yet the feature functionality and cost savings provided by SIP [remain] big enough drivers to propel enterprises to migrate to VoIP.”

And so it will not be, to use Disso’s words, “game over” for VoIP. Furthermore, an increase in mobile and location-independent communications will also not have any impact on the future purchase levels of VoIP, according to Swyx’s Russell. He believes IP will replace GSM as the transmission platform, and not just for voice but for video and data as well. All fixed or mobile communications devices will therefore become an integral part of the wider office network. 

“At the moment, we’re at the halfway stage where we’re using dedicated SIP trunks and links. But down the line, with increased bandwidth, we’ll be looking at a giant peer-to-peer network where everyone can talk with any other individual or company, with a high quality of service, and without the need for carriers or billing for voice minutes.”