It’s all about the network

BrandPost By Alan Stevens
Aug 17, 20115 mins
Cloud Computing

“In order to communicate, you need to be adequately connected…” – not sure if that’s a real quote or a truism I just made up, either way, there’s little point even thinking about unified communications until you’ve first made sure that supporting  networks are up to the job. And that’s not as easy as it may sound, with pitfalls aplenty waiting to bring that shiny new UC application crashing to a halt before it even gets started.

Made for sharing?

One of the biggest problems is historical in that the packet-based networks we all use were never really designed to carry real-time communications traffic at all. Indeed the first networks were much more mundane affairs, invented long before integrated voice and video was even dreamt of, and built primarily to share files.

Resilience rather than latency was the main concern here and I clearly remember a demonstration of first generation Ethernet hubs where the presenter pulled out a patch cable mid-way through a data transfer, then plugged it back in again a few seconds later. Because of the error-recovery facilities built into TCP/IP and the supporting Ethernet layer, the transfer simply carried on as though nothing had happened.

Try that mid-way through a VoIP phone call or during a video conference and you’ll know all about it!

So, too, will those trying to communicate over the failed connection, and it’s not just lost connections that can have an impact. Voice, video and other real-time traffic is also acutely sensitive to transmission delay (latency) and variation in throughput rates (jitter) with, one of the biggest causes of such problems, the need to share the network and its limited bandwidth with other applications.

Getting the network right

On the plus side, networking technology has moved on since that demonstration. Shared network hubs have long been replaced by switches and the bandwidth on offer has sky-rocketed, from the meagre 10Megabits per second available at that time to 10Gigabits and beyond. Even on wireless we’re looking at 100Megabit throughput already, with Gigabit WiFi due any day now.

All of which helps, but bandwidth alone isn’t enough and on a small business network, reliant on low-cost unmanaged Ethernet switches, it’s all too easy to run into performance issues when deploying VoIP, video and other unified comms applications. Issues which tend to manifest themselves as reports of poor call quality, unreliable connections and a “slowing” of the network as a whole.

That’s because unmanaged switches do little more than forward packets around the network, treating each packet as equal, irrespective of the application involved.

Now, there are ways of getting around this, of course there are, common mechanisms being either to separate out the different traffic flows using Virtual LAN (VLAN) technology or to prioritise real-time communication packets over those from file sharing and other less sensitive  applications – or both. However, you’ll need a lot more intelligence in the network than found in most commodity switches to do this. What’s required are managed switches or, for those on a budget, slightly cheaper “Smart” switches with the ability to route traffic over dedicated VLANs and prioritise real-time traffic flows using industry-standard QoS (Quality of Service) protocols.

On larger networks Layer 3 switches may also be required and, possibly, switches able to identify and route traffic higher up the networking stack, based on the type of application involved.

Bear in mind too that it’s no good simply deploying one or two switches with these features on-board and expecting instant results. A complete end-to-end implementation is needed to fully feel the benefit, with support for the same VLAN and QoS technologies on access switches as well as on those used to create aggregate those edge networks and at the core where Internet and other WAN gateways are, typically, interfaced.

Network centric approach

Getting the network right is a key part of any UC rollout, and there’s a lot more to it than simply buying a few new switches. Specialist skills are required to design and implement a suitable networking infrastructure capable of handling real-time communications traffic and to properly configure the various protocols and technologies used to make it all work.

Little wonder then, that the top vendors in the UC space are also leading lights in the world of networking, with service teams dedicated to getting this part of the solution right.

That said, you don’t have to buy your network from your UC vendor or stick with just one brand of networking hardware to make it all work. You can do that, and many do, but there are also plenty of specialist companies with no particular vendor axe to grind, willing to advise and provide practical help with UC rollouts and all they entail.

The main thing is to start at the network and get that right before all else. After all, as I said at the beginning – and I’m determined for someone to adopt this as a slogan –  “In order to communicate, you need to be adequately connected…”

This article is written by Alan Stevens and sponsored by Avaya. The opinions reflected in this piece are solely those of Alan Stevens and may not reflect those of Avaya management