Bandwidth's poor relation

On the day Telecom NZ announces it's "brand new network" - doesn't look too new to me to be honest - I thought I might touch on the subject of mobile applications and one reason why they don't work!

Most IT solutions struggle to perform when delivered on an internal corporate network where the servers that the application run on are two floors away from the users that are using it. The connectivity issues that arise in this scenario are pretty slim and usually completely discarded in the risk register of a project. The project has far worse things to worry about. 

However when you start pushing that interaction across another kind of network it can all start getting a bit difficult. For solutions to work well they need to function from end to end and if one of those ends is a lot further away than normal things can get nasty.

The problem tends to stem from the poor relation of Mr Bandwidth. Mr Bandwidth is the guy who is the shining star and gets all the press coverage. He is constantly seen as our salvation in the shiny new world of broadband nirvana. But he has a poor relation - Ms Latency. Few people have heard of her and even fewer understand what she's about.

Let me explain, when you look at the performance of systems the easiest analogy to explain what is going is a comparison with roads. 

Bandwidth is the number of lanes on the highway, that's easy eh? The more lanes you have the more cars that can travel down the road so bandwidth is really simple to manage...isn't it? Well it is if we all drive Ferrari's at 240kph. But what happens if we only have clapped out old Morris Minors? 

There's the highway laid out before us and all we can do is 30kph. When we're stood at the other end of the road the same number of vehicles are going by but they've taken 8 times longer to get here (30/240 for those mathematically challenged of you!).

That difference in speed is latency. The real problem, that's kept quiet (especially by the mobile networks) is that bandwidth is generally really easy, and cheap to increase, but latency is really expensive and very costly to reduce. And when it comes to mobile networks that problem just gets worse.

Now if your application, that has been developed for you on your network, is not aware of that change in latency there's a good chance it will never work. Not unless you can "change the laws of physics".

So be careful, just because you can drive to the dairy doesn't mean that you can get to Sydney in your car! :-)