The Wired Revolution: Myths, Realities And Trends
To Watch
by Jeff Waters, Director, Interface Products Group
& Andy McLean, Director of Engineering, Ethernet Products
National Semiconductor Corporation
Where will technology take us over the next 10 to 15 years?
We believe it will be driven by the fundamental needs most of us have -- needs that are timeless and, if anything, are more under attack these days:
All of the above centers around connectivity -- and here's the surprise: connectivity will be driven more by wires, and less by wireless.
It sounds crazy. It runs counter to wireless technology trends such as Wi-Fi hotspots, 3G and 4G cellular, Bluetooth and a lot of other wireless consumer technologies. And wireless hype isn't limited to consumer applications. Most of the buzz these days in machine-to-machine (M2M) connectivity is wireless, with quickly emerging technologies such as Zigbee and RFID.
Why wired? It's simple: wireless will be used where mobility matters, and wired will be used where it doesn't. Wireless mobility always comes at a cost. Wireless computer mice are a great example -- they're seldom used because the mild pain of having a battery and the intermittent link-loss outweigh the minimal value in not having the wire.
By 2015 we see a world of mesh networks connecting machine-to-machine, machine-to-consumer, and consumer-to-machine with immediate potential for tens of billions of connected nodes, both wireless and wired. As this happens, the power of Metcalf's Law (which states that the usefulness of a network equals the square of the number of users) comes into effect and we see that the value of a device becomes increasingly tied to its networkability.
Debunking The Wired Myths
Wired and wireless have their strengths and their limitations. But to sum up the situation in a phrase: "the death of wired networks has been greatly exaggerated." Here are the myths and realities of the wired world, circa 2006.
MYTH #1: wireless technology will replace wired
REALITY: The explosion in wireless nodes is placing more demands on the wired enterprise due to the need for aggregation for long-haul transmission. In the M2M paradigm increasing up-link or back-channel demands will also lead to more symmetrical bandwidth requirements, which are more easily served with wired than wireless technologies.
MYTH #2: wireless is easier and cheaper to implement than wired
REALITY: Provisioning, tracking and maintaining wireless-enabled nodes are inherently harder than wired. Often wireless nodes have to be configured over a wired link before they can go live on the network. And the cost of a wireless node is expected to remain 2x to 10x the cost of an equivalent wired node.
MYTH #3: wireless is more flexible than wired
REALITY: Existing wireless networks, even in a home, typically require one or more wired access points to function. And anyone that has attempted to set up a wireless network in their home knows that "the hidden access-point" in the closet or basement or attic makes for weak access -- more often than not the access point is anything but hidden and the access is anything but pervasive. And, on top of that, it needs power and a wired Ethernet connection. One thing you'll notice about most wireless homes is that they have a preponderance of blue cables and RJ-45 plugs in the wall. It's ironic that a major breakthrough in the deployment of wireless technology has been in remotely powering access points using power-over-Ethernet (PoE). With PoE, power is delivered to the access point on the same cable that connects it to the network.
MYTH #4: new installations will bypass wired infrastructure and go straight to wireless installations
REALITY: Justifiable concerns over the ruggedness, reliability and security of wireless connections will continue to hinder their deployment in many applications. The physical nature of wired networks offers a first line of security and the ability to cross physical boundaries such as steel, water and reinforced concrete with ease. Any moderately mission-critical function requires wires, and will so for a long-time. It's true for television as it migrates to high definition, needing continuous high-bandwidth links to support the frame rates and resolutions required to satisfy our ever-growing sophistication in assessing the quality of the video. It's also true for security -- a wireless monitoring of a tunnel or bridge could be readily disabled with one blocking device, much in the same way the casinos in Las Vegas disable your cell phone at the blackjack table. It's even true for functions as life-critical as the audio feed from your MP3 to your ears.
Myopic Or Visionary?
We've debunked the wired myths, but what trends are driving the technology?
Simply put there is an inevitability of a connected world. While wireless has enabled pervasive voice connectivity the practicality of wired will accelerate ubiquitous machine-to-machine and human-to-machine connectivity. Here, then, are the trends to watch.
TREND #1: M2M communication will inherently require tight feedback loops well beyond traditional control applications
As we rely more and more on real-time M2M communication our expectations for accuracy and precision will increase. This, in turn, will require lower latency and reduced jitter in elements in the network. This challenge is already being met by real-time Ethernet while advances in wireless technology are largely ignoring this factor. Imagine the problems if your car's drive-by-wire steering wheel had a two-second delay and accuracy of plus or minus 10 degrees.
TREND #2: wired technology increasingly enables intelligent networks and smart peripherals
As available bandwidth continues to grow exponentially there is less need to centralize the compute tasks in traditional client-server architecture. In many applications the computing will be accomplished in the wires, with two or more machines talking to each other over a very high-bandwidth link.
TREND #3: wired networks proliferate where security, reliability, flexibility are critical
Recent advances in wireless have focused on quality of service (QoS) features, including mesh networks that offer a degree of self-healing and redundancy. However, even more advanced QoS features are being developed on wired networks. Wired connections are built over inherently more constrained media than the free air of wireless. By carefully monitoring the effects of impairments on the data as they are transmitted over the wires, it can be statistically predicted when a failure might happen. This allows a connection to be rerouted and repaired before the data are lost. In a more catastrophic scenario, a failover between connections can occur in a few nanoseconds at the wired physical layer, compared with wireless, which first has to determine that a connection loss is not simply a temporary condition as a result of signal fading.
The lack of a power-over-wireless equivalent to PoE also reduces the real flexibility of wireless. If you need to run a wire for power then you may as well run a wire that will offer more than 10x the bandwidth, is more reliable and cheaper than wireless.
TREND #4: applications continue to emerge with bandwidth requirements that can only be served with wired interfaces
High-speed serial wired interfaces such as USB 2.0, Firewire and HDMI have already commercialized gigabit data rates that, until recently, were only available in expensive equipment in the enterprise. Wireless will inevitably and eventually evolve to gigabit. However, the bandwidth gulf between wired and wireless will continue with newer wired technologies such as PCI Express already offering up to 80 Gbit/s of throughput.
Back To The Values Argument
So, what does all of this talk of Metcalf's Law, tight feedback loops and QoS have to do with our daily fundamental needs?
Keeping our families safe and healthy will be driven on the backs of wired connectivity, making sure that you'll have as impenetrable a connection as possible for security in homes, tunnels, bridges or ports. At some point in the relatively near future you will at long last be able to close the miles between you and your loved ones through high-quality videoconferencing in the home, courtesy of high-definition televisions, a faster Internet and -- most definitely -- wires. And lastly so many of the mundane tasks that take up your would-be free time will happen without your knowing -- think of it as the automatic bill-pay concept taken a step further where now your need for another gallon of milk, or for chlorine in your pool, will be taken care of for you through wires.
Yes, we envision such a world…and the wired revolution will only
be complete when teenagers are putting designer-colored CAT-5 cabling on
their wish-lists, and parents are complaining about the good old days when
you knew your CAT-5 from your CAT-6 just by looking at it.