Fixed or mobile in the unified comms world?

29 May 2015

While mobile devices give consumers a wide variety of options that landline phones cannot, fixed line infrastructure still has a unique place in enterprise networks.

While mobile devices give consumers a wide variety of options that landline phones cannot, fixed line infrastructure still has a unique place in enterprise networks.

A key part of the unified communications (UC) proposition is the promise of a more consistent user experience across a wider range of communications channels and features, including mobile users. 

To achieve this, a critical task is to tightly integrate the server-based communications products and application functionality into the UC infrastructure. This involves a convergence of telephony PBXs, email and calendaring, voicemail, audio conferencing, web conferencing, and instant messaging. It also encompasses rich presence server applications; multi-party video-conferencing functionality; and improved access to corporate communications features for mobile staff through mobility applications such as enterprise-class email software.

We often hear how the fixed infrastructure is being used less in the public network. This is because for the consumer, mobile phones provide a large variety of options that landline phones cannot. Mobiles offer a quicker way to communicate with friends, family and business associates. 

In the business world, applications exist that will extend voice and UC applications to a wide range of mobile platforms including Android, BlackBerry, iOS and Nokia’s, while integrating with major PBX and UC systems such as Cisco, Avaya, Nortel, ShoreTel and Microsoft. Users can leverage a single converged device for both business and personal communications, and access desk phone and UC capabilities on their devices without having to learn a new interface. 

So what effect do fixed line and mobile platforms have on the UC objectives of improved collaboration, increased worker productivity and reduced telecoms costs?

Improved collaboration

A collaborative working environment supports people in both their individual and cooperative work, thus creating a new class of  ‘e-professionals’ who can work together irrespective of their geographical location. 

Bandwidth issues at fixed locations originally limited full use of collaboration tools. This has improved as cabling developments have delivered support for greater bandwidths to the user. However, while these issues have now been resolved in cabled environments, they are made worse with the use of mobile devices. 

Despite this, business collaboration is increasingly taking place on smartphones, media tablets and next-generation IP phones. IT and telecom managers are being asked to extend voice, video, messaging, conferencing, and social desktop collaboration experiences to a wide variety of mobile devices. 

Mobile collaboration utilises wireless (Wi-Fi), cellular, DECT and broadband technologies to enable effective collaboration independent of location. For instance, traditional video-conferencing was once limited to boardrooms, offices, and lecture theatres. Today, technological advancements have extended its capabilities for use with discreet, hand-held mobile devices, permitting true mobile collaborative possibilities. 

Collaboration as a benefit of UC is equally valuable to the enterprise whether mobile or fixed infrastructure is used. The main challenges for businesses are related to providing a scalable design that can support new mobile users and applications without affecting the performance of existing network applications, and ensuring that performance is not degraded for bandwidth sensitive voice and video applications.

Improved employee productivity

It is a simple fact in the corporate world that when time is saved, money is saved. And having access to the right information quickly and easily will save employees time. According to one report, if UC is applied to 50 company workers each with a salary of around €40,000, the expected annual savings will be in the region of €942,000.

In a modern workplace, employees communicate using a variety of devices and technologies such as text, email, voice, video-conferencing and instant messages. In order to maximise employee productivity, a business needs to maintain efficient and effective communications both within and outside the organisation. Mobile connections for maximising employee productivity are therefore key.

Reducing telecoms costs 

A major part of the reduction in communications costs from deploying a UC solution relates to the cost of inter-site connections. These have been cut with the introduction of SIP trunking – firstly by the convergence of voice, video and data which reduces the wasted bandwidth, creates more efficient connections, and makes better use of the available capacity; and secondly, by the reduction in the costs of connections. 

A report by Infonetics Research found that of the respondents to a survey of North American businesses, 58 per cent said they will use at least some SIP trunks in 2015. That’s a dramatic shift from 2013 when 38 per cent said they used some SIP trunking.

SIP trunking involves connecting all corporate voice traffic to service providers’ networks over a single IP connection rather than over multiple TDM lines. Telecoms savings of up to 50 per cent can be had depending on the individual network. 

Businesses can expect further cost savings to come from cutting the amount of hardware needed to terminate copper circuits at corporate sites, therefore reducing maintenance. Locally, mobile users are still typically connected to other sites and to the internet using SIP trunks, so this element of cost saving applies whether in a fixed local infrastructure or a mobile one. 

A second key area of telecoms cost saving with UC and IP telephony is the moving, adding or changing of users connected to the network. Research shows that in fixed networks the largest single block of IT staff time is spent on moves/adds/changes (MACs) of users. Problems with Ethernet ports, cables, server and application access, securing sensitive data while allowing selective access, all complicate the administration of user accounts and
raise network maintenance costs. 

Traditional MAC savings are calculated on the basis of €100 for each change saved for larger businesses and €50 for each change saved for smaller ones. These changes can include the addition or deletion of new employees, alteration of access privileges (such as when a probationary employee becomes a permanent one), or other modifications such as a changed voicemail greeting, call forwarding, automatic call notification, the addition or revision of other contact phone numbers and email addresses for employees. 

IP simplifies this situation and reduces the costs of MACs in both fixed and wireless networks by locating user devices by their IP address automatically, and re-allocating their security and permissions to their new location. 

MAC costs are more generally associated with fixed infrastructure UC deployments since mobile users are, by definition, mobile. However, it should be kept in mind that for mobile users some of the costs still exist since the need to manage authentication from a central server, utilise single-sign-in, or improve security by enforcing a password expiration policy still exist.

What does UC need from the infrastructure?

The enterprise unified communications infrastructure is composed of server-based products and software that provide a central platform for communications, the distribution hardware (including routers or switches), and the endpoints which provide user access to voice, data or video that connect to this infrastructure. These elements are needed whether the medium is wireless or connected. 

UC places strict requirements on IP packet loss, packet delay, and delay variation (or jitter). Therefore, you need to enable QoS mechanisms on switches and routers throughout the network. For the same reasons, redundant devices and network links that provide quick convergence after network failures or topology changes are also important to ensure a highly available infrastructure. 

Design of the infrastructure requires building a robust and redundant network. This does not just apply to the fixed infrastructure; WLAN infrastructure design also requires understanding and deploying QoS to ensure end-to-end voice quality across the entire network.

Security is a critical consideration since the impact of any data breach is bigger in a unified comms world, and with your workforce on the move and connecting remotely, you need to know that your organisation and its proprietary information remain protected.

Whether the network is wireless or fixed, the demand on the network infrastructure to meet the challenges of security, availability and QoS are the same. The main difference for the network designer between a wireless and a connected infrastructure is bandwidth, and more specifically ensuring availability of quality bandwidth for all users irrespective of location.

Fixed infrastructure bandwidth

With hardwired cabling infrastructure, the physical layer is expensive and limiting in its physical location. But it is also predictable and consistent, and the bandwidth costs are lower than for the equivalent mobile bandwidth. 

Although replacing cabling is expensive, potentially disruptive and should be avoided for as long as possible, the speeds supported by it has increased incrementally over the last 15 years with changing standards to meet the demands for ever higher speed. With hardwired cabling you can ensure that your network will handle both the bandwidth needed and the power requirements of a UC infrastructure.

Using a homogeneous cable plant means that cabling can be installed more quickly and uses the same termination hardware throughout. This makes every cable usable for all purposes – important if one of your cost-saving arguments for UC is the reduction in costs of MACs. In a good design, all connections use the same patch cord types and this removes the risk of poor performance from mistakenly using a low-grade patch for a high-performance connection.

Adding most or all of your devices on IP with PoE is a smart way of keeping your fit-out budget down by reducing the required amount of structured cabling. 

Even with the compression capabilities available today, good quality voice and video are highly dependent on having bandwidth available and a fixed infrastructure will ensure you have the bandwidth you need.

A collaborative working environment creates a new class of ‘e-professionals’ who can work together irrespective of their geographical locations.

A collaborative working environment creates a new class of ‘e-professionals’ who can work together irrespective of their geographical locations.

Mobile bandwidth

Let’s look first at local Wi-Fi as an alternative to fixed infrastructure. A WLAN or Wi-Fi system needs to be capable of delivering high-quality voice, multimedia and business applications, while meeting stringent security requirements and delivering seamless mobility functionality, easily and cost-effectively. It must also be quick to install and simple to operate. 

The argument for Wi-Fi compared to making an investment in wired technology is that wireless will deliver everything you need for less money, with increased flexibility and as good or even better security than legacy wired systems. But this argument works for small Wi-Fi hotspots and not so well for enterprise-wide deployments. 

The average cost to purchase and install a professional Wi-Fi network varies between £1,500 and £3,000 per access point. Given an AP’s limited Wi-Fi coverage radius of 30 to 60 metres, many of them are required to extend coverage. And each AP must be connected to the network backbone to provide complete coverage. Furthermore, people and objects constantly move around, creating obstacles and reflection points for Wi-Fi radio signals. True mobility changes planned coverage patterns which can create poor QoS.

Mobile data doesn’t scale like fixed connections, and designing a local Wi-Fi network to handle fluctuating levels of usage in an area such as a call centre or a busy sales office with hot-desking workers means providing sufficient bandwidth for worst-case situations. All of this therefore creates a very expensive and oversized Wi-Fi network.  

The design of Wi-Fi hotspots only works because of the assumption of users moving in and out of the area. In an office where good quality network performance is needed for focused groups of relatively static users, the costs are unrealistic for the business. 

As an example, take a requirement to provide sufficient capacity to support 100 users in a given area. There are a number of trade-offs that can be considered here. If all the users are assumed to be active at the same time, and if each user is allocated 1Mbps of bandwidth, then the network is going to have to support 100Mbps. If each user is allocated 256Kbps (similar to a consumer DSL line) then the overall network needs to only support an aggregate of 25Mbps. If it’s assumed that only 10 users are active at any given time, then the aggregate requirement drops to 2.5Mbps – a reasonable requirement in a Wi-Fi network. 

It can quickly be seen that Wi-Fi will work for a limited number of mobile users in a defined area, but prove costly for an intensely active work area such as a call centre or sales office.

The second mobile network is of course the operator’s wireless network. Even if you’re not a big video user, the normal sorts of messaging and web traffic created by a PC can quickly overload a wireless network. A typical PC has a more or less continuous connection to the web, so instant messages and web app updates can ping back and forth constantly. 

But to conserve battery life and stretch network resources, a smartphone doesn’t talk to the network continuously; it basically says ‘hello’ to the network, sends a message or a bit of data, and then says ‘goodbye’. Each little message and each app ping creates its own set of hellos and goodbyes. Send too many and they can overwhelm an operator’s servers. Web apps send too many.

More significantly, the overall bandwidth available to operators is not sufficient to support a wireless world. Single mode fibre has a bandwidth of as much as 100,000GHz or 100 terahertz, whereas the total available spectrum for mobile communications provides bandwidth of no more than 3GHz. If data traffic continues to grow at its current pace, we’re headed for a situation in which the cellular networks will be overloaded and prices will rise. 

The mobile operators’ networks are useful tools for business users and an easy low-cost solution for start-up operations, but shouldn’t be relied on for a business communications infrastructure in a large business.

Horses for courses

Mobility and unified communications are natural bedfellows. With UC and collaboration in place, enterprise mobility accelerates faster, and organisations experience easier deployments of devices and enterprise apps, improved collaboration between employees and partners, enhanced customer engagement, quicker decision-making, and substantial productivity gains across the business.

There may be many routes to achieve UC but the journey always begins with fixed line telephony because while much growth and innovation is taking place in the mobile space, fixed line remains ubiquitous and still accounts for a substantial proportion of enterprise telecoms expenditure.

The robust and reliable infrastructure provided by fixed line telephony combined with the bandwidth issues associated with mobile means that for large businesses fixed line infrastructure is not going to be redundant in a UC environment in the foreseeable future. 

To handle the bandwidth demanded by today’s UC applications, the capacity of the fixed infrastructure is going to be required. But there will be areas in buildings – particularly for the last 30 metres of connectivity – where users in the UC environment can be most effectively served by Wi-Fi or DECT networks to accommodate mobile users, for example in visitor areas and lobbies. 

There will also be areas where both fixed and wireless connections are needed, such as in the conference room with a fixed line conference video phone and a wireless service for personal calls. To reduce the cost of deploying in areas where only a limited amount of connectivity is needed, Wi-Fi will be the best choice, for example in loading bays or reception zones. 

Equally, there will be areas of high bandwidth usage such as call centres and sales offices where fixed line UC connections will continue to be the best option for call and video quality, and for the comfort of using a fixed phone with ergonomically designed handsets.

The ultimate aim of UC is to rationalise devices and channels so that users are able to communicate instantly using whatever method is most appropriate at that point in time. That might be a fixed phone, smartphone, PC or tablet, and it could be communications via SMS, instant message, voice, video or email.