application bandwidth calculator

[korbenda11as]

Anyone,

Our local group is trying to develop a formula that will somehow compute the bandiwdth value that will be needed by an application that is about to be develop. From here, we want to know specific questions that we can ask with our application developer in order for us to compute the necessary bandwidth needed by an about to be develop application.

This application bandwidth calculator will compute for the bandwidth required for a certain application that will be hosted on different locations (regions) of data centers. Also, is it possible to compute for the backend processes of these applications? what particular questions that can be apply in achieving this?

Thanks,

[Jon Marshall]

This and your other question are tricky subjects.

There are commercial products available that will allow you to test an application on a network simulation. The last place i worked we used Shunra which is one of those commercial tools -

Shunra

However the key thing is if you can get access to the application developer which it sounds like you can. They should know which protocols they are using although even then it can be surprising how many developers do not fully understand this. They should however have some idea of how much data is contained in an average request, how much data is contained within an average response and how many requests/responses are made in an average day if this is an in-house application.

Bear in mind that it's not just the network that needs sizing ie. the backend server would need to be specified and so someone within the app project should have some idea of how much data is being moved.

One key thing that comes up all the time is that a developer often develops the app on a LAN environment, rolls it out to the WAN and is then surprised when it doesn't perfrom as well !

Do you have a test network where you can prestage the application ? If you do this is where something like Shunra can help.

Jon

[korbenda11as]

Thanks Jon for your reply, however, the main challenges that we are currently facing is that the application that we want to provide bandwidth information is just about to be develop. We are targetting a proactive move while the application is still on its planned stage and by gathering valuable information from the developer we can derive a formula that will compute for the bandwidth needed.

The questions that you provided are meaningful, do you know on how to derive formula out of it? For the backend process, what specific questions that we can ask with the developer that can help us formulate a solution for bandwidth values. We are not targetting a 100% accurate figure what we are up to is closer to the real bandwidth values.

We are anticipating the fact that the developer that will use this questionnaire somehow do not know most of the question since as I have said the application is just about to be develope and this is a challenge for us.

The reason i post this topic to this forum is to gather ideas, comments and/or recommendations on how to do it. If anyone knows of a link or reading materials that can give us valuable information in calculating this bandwidth requirement of an application that is about to develop, kinldy forward it to me.

Regards,

Korben

[Jon Marshall]

Korben

The questions that you provided are meaningful, do you know on how to derive formula out of it?

I thought i already had ie.

(average request size + average response size) x average number of requests/responses per hour

will give you a rough estimate of how much bandwidth will be used across the WAN per hour for this application.

As for the backend it depends what you mean. If you mean an app server to a database server there is nothing magic about it, again it is simply using the formula above.

Where testing helps is -

1) to confirm that the figures given are accurate
2) to confirm that the app can still perform adequately with latency across the WAN

Jon

[korbenda11as]

Hi Jon,

This is great and appreciate it a lot, the formula looks good, can this be applicable to any type of application? (e.g. web based, applications that involves download/upload, thick/thin client, non web based application, content-rich application, etc.).

For the backend process, this involves WAN connection, whereby, backend servers/databases are located in other regions. How to approach this kind of scenario?

Regards,

Korben