The Earth Defense WIMAX Game
Posted by Dekel Cohen on 10 Aug 2010
Years ago, there was a terrific arcade game called “Space Invaders.”
I used to love that game. You started out by shooting at a row of alien invaders, whose movement would increasingly speed up. At first, it was easy to shoot them all. But then came the next level, where the invaders took out some of my defenses. And the level after that was even tougher.
Eventually, I reached a stage where the invaders out-maneuvered me. There was nothing I could do to stop them.
And that – in a funny way – is where things stand with WiMAX. It easily shot down the problems at the first levels. In other words, WiMAX has proven itself as a technology. It works and it can make a difference for network operators. But here they are, and it’s now time to face the fast moving invaders.
As a comparison, in Space Invaders the first level moved at a speed of 10 seconds from left to right, and the next level at 6 seconds. Then it became a second or less, and you can imagine that a fair amount of technique would have to come into play in order to win the game.
As WiMAX reaches maturity, operators all over the world are moving field trials into actual deployment, and they are having their share of network-related issues concerning it.
And here’s the first level becoming the fifth: once mass deployment kicks in, providing competitive services overrules technological issues. And what makes things most interesting is that these challenges did not appear at the proof-of-concept stage. They are directly related to moving up-in-class to mass deployment.
Let’s look at some of these issues, and how WiMAX will have to address them to avoid being taken out.
Case #1: backhaul architecture
Deploying a tree topology, which is the cellular 3G best practice, may be traditional, but there is a scalability issue, due to bandwidth growth pushing this architecture to a point where nodes will require constant upgrades in connectivity.
A ring topology addresses the issue of protection, but its scalability might be even worse than that in a tree topology, because the ring is now required to carry several base stations, and upgrades require the full ring’s bandwidth.
This brings us to the problem of over-provisioning vs. QoS mechanisms. This problem dates to the beginning of the decade, and has an inherent effect on capex as well as network architecture. Over-provisioning means you build your network on Day 1 with more than the required resources, while QoS mechanisms require longer network design and better understanding of network management.
Case #2: ASN (access services network) technology
Nowadays, there are two basic options for the ASN – Layer 2 or Layer 3.
A Layer 2 network centralizes the routing, making the network more robust, more manageable but less flexible.
A Layer 3 network is highly flexible and, in small scale, operates quite well and can be easily managed. However, a Layer 3 network passing a certain number of nodes can result in effects that can make operators’ day-to-day operations very complicated. It reminds me of the saying, “quantity is a quality by itself.”
Case #3: subscriber management
With the natural evolution to next-generation networks, WiMAX networks, as any other network, require increased intelligence to cope with the challenging demands imposed by advanced services. For example: take a network with a large number of subscribers wanting to download a high-bandwidth video at the same time. The result? Bottlenecks. Eventually, this will lead to higher churn rates.
IP networks are currently at the learning curve stage of this problem, using a variety of methods to minimize the adverse effects to the network and to day-to-day services.
Winning over the fast moving invaders
WiMAX networks are now “crossing the chasm” to mass market deployment. To go back to the “Space Invaders” analogy, they are now at the fifth level. If they are to hope for a shot at the next levels of the game, they have to make sure they have their act together. In telecom talk, this means they must undergo the painful stage of network integration.
Most of the challenges associated with mass deployment can be resolved. If the operators approach this with a smart game-plan – and a self “turbo button,” WiMAX networks are on their way to becoming a faster than ever, wireless broadband Earth defense.
Oren Barkai and Dekel Cohen
Topics: Legacy Networks