Weighing up the benefits of alternative broadband infrastructures
There has been much written over the past few years about broadband technologies. Whether wired or wireless, there never seems to be a lack of noise coming from would-be world-changing suppliers when it comes to broadband technology delivery.
On the wired front we had the copper versus fibre argument. Fibre can do the job but it is still very expensive. Copper moved from just ADSL to Metro Ethernet (which became Carrier Ethernet) and suddenly running multi-megabit connections into offices over copper is not an issue.
At the same time, the wireless brigade moved out of the local area network and away from all the proprietary (and often bizarre) mobile wireless technologies used by the likes of the emergency services and announced technologies such as Wimax on the extended wireless Lan, and 3G (and beyond) for mobile. And now we have talk of convergence between Wimax and mobile to create a total, broadband (of sorts) wireless coverage - in concept at least.
Not that we are limited to these technologies. For example, there is ETI's Multibeam broadband wireless technology, which is claimed to be 10 times more cost-effective on a coverage:cost basis than Wimax and offers huge coverage from a single antenna.
So what better than to line up one wireless broadband technology provider and one wired broadband technology provider and ask them to explain the potential benefits of services provided by a broadband wired or wireless infrastructure?
Benefits of wired broadband
Bring on the wired boys - in this case Craig Easley from Actelis, a Carrier Ethernet product supplier. Easley believes that they key word here is "Ethernet", in that it allows carriers to easily support a number of critical distributed applications in both the public and private sectors.
"These applications all need more bandwidth to power the next generation of applications and services, most of which are beyond the reach of fibre too," said Easley.
"Basic Ethernet services are being used to deliver the next generation of business services, including virtual private networks, high-speed internet and voice over IP."
Easley believes that the biggest challenge for carriers is conquering the last mile, and he sees Carrier Ethernet over copper as being the cost-effective way to rapidly deploy high-performance and highly reliable Ethernet services over an existing infrastructure.
Benefits of wireless
So what is the response from the wireless division - in this case Andy Hood, managing director at Sarian Systems, which provides IP routers for both wireless and wired infrastructures?
Hood believes that wireless networks offer many benefits over wired lines, hitting on valid points such as geographical coverage being more widespread and less restricted by extreme terrain, and that applications can be fixed or mobile, enabling connectivity while on the move. He also points out deployment benefits with wireless.
"Deployment times are instantaneous, with no set-up or installation costs. Tariff tie-in periods are usually on a monthly basis, so companies can operate lean networks according to their monthly requirements," he said.
Obviously these cost savings can be passed on to an enterprise user to close the gap on what Hood admits has historically been a factor in favour of the wired alternative.
"Wired networks have traditionally had several benefits over wireless ones, with higher speeds, lower cost, lower latency and generally greater reliability, but that gap has been closing for some time," he said.
Key to Hood's argument is the emergence of HSDPA (High Speed Downlink Packet Access), a 3G-based protocol which supports download speeds of up to 14.4mbps and beyond in future.
The next stage on the wireless roadmap is HSUPA (High Speed Uplink Packet Access), which companies such as Vodafone have already started testing with great success, according to Hood. HSUPA promises uplink speeds of up to 2mbps - as opposed to 384kbps using HSDPA - and improved latency (ping times) from 120 milliseconds on HSDPA to less than 100 milliseconds.
Meanwhile, he sees a hybrid of HSDPA with DSL as being one alternative scenario to provide a fast initial deployment or ongoing back-up.
Wired and wireless together
It seems wired and wireless can live happily together. Or can they? Do we need wireless delivery to a fixed environment at all? After all, there has been much promise of widespread broadband wireless delivery, but little sign of it to date, while Carrier Ethernet is now an established technology.
What have been the problems and what has been missing? Let's kick off with a response from the wireless supplier.
"Lack of suitable devices and some delays in network deployment certainly limited initial growth, as did high initial data tariffs, but the latest research indicates that there are currently in excess of five million HSDPA subscribers, and huge growth is expected to take that to between 600 million and one billion by 2012, reflecting it is position as the future wireless technology of choice," said Hood.
So what is the wired supplier's view on this?
Easley cites the obvious benefits of using Ethernet - an established standard with almost two billion ports deployed worldwide - over copper: an existing infrastructure, making for a relatively simple system to deploy and one that is available now. He did note that Carrier Ethernet is not exclusively a wired technology, however.
"It is available over both Wi-Fi and Wimax. However, there have been implementation challenges that have led to disappointingly low numbers of deployments of Ethernet over wireless."
Easley believes the issues with Ethernet over Wimax are to do with uncertainty.
"Wimax is attempting to create the same interoperability and conformance that the Wi-Fi Alliance has achieved for the 802.11 standard, but it is not yet clear how successful this will prove. There is still confusion over what the final standard will be and how robust it will prove for critical and real-time applications."
Easley also thinks the waters have been muddied by the natural desire to support mobility within Wimax.
"The thinking was that if you are going to have a wireless network you might as well allow people to roam with portable devices. But supporting mobility at broadband speeds is proving a challenge and has required an extension to the standard, IEEE 802.16e, creating more confusion.
"Therefore, Wimax is not currently a viable candidate for Ethernet access, whether or not mobility is required," he said.
Regardless of the technology, we need to ask the question: have the operators/service providers truly got their act together in terms of providing cost-effective deployments (both for them and their customers) that not only offer bandwidth (wired or wireless) but also a range of services on top that enterprise customers need?
Hood said, "I do not think they actually have yet, but there are many key elements here that are beginning to fall into place. Converged mobile/PDA devices have advanced tremendously in the past year and they are a key enabler for true mobility in advanced service delivery and more widespread take-up."
● Steve Broadhead is founder and director of Broadband-Testing Labs
Wimax: the expert viewWaiting for the WiMax wireless revolution >> www.broadband-testing.co.uk
This was first published in November 2007