Why?
Why not?

What is it?
Paola is a web interface into a collection of tools i have written. It will give you NSP (network service provider) information between whatever server is running it and a user specified IP address or hostname. In addition, it will also do an (optional) application layer check to further verify performance.

How does it work?
The NSP section of the check will calculate incurred latency while crossing over different NSP's, the time displayed is the amount of latency that NSP added to the overall time it took the packet to reach its destination. The application layer check uses Anna. It currently only does a HTTP check, but i may add more if i get enough requests. Also, the application check will be ran against the IP address of whatever the NSP check was destined for, this way it wont get another ip address if dns is used for load balancing. It will send a Host: tag along with the request to make sure the destination server handles it properly.

What are its limitations?
There are always many limitations when you have an application processing information that normally a human engineer looks at. With that being said, the NSP code has no reliable way of knowing the physical location and actual distance covered between hops. For example, pointing it to www.mtv.com, under perfect network conditions, you will see about a 60-65ms incurred latency over gblx (globalcenter).. this is because the check originates in northern california, and finally ends up in NYC. That 60ms is a perfectly reasonable incurred latency for traveling across the USA with current internet topologies.. but its not exactly trivial for an application to know this. :-)

Future plans for it?
Im thinking of setting up a few of these boxes in disperse locations.. and allowing checks from any/all of them at once, to a single point.. it would be easy to setup, but i have to figure out the time and logistics of actually mantaining it. Im also thinking of collecting the data for the nsps so that a running statistical database would be available to everyone for the nsps in relation to source/destination metrics. Lastly, im thinking of expanding the interface to allow users to automate these checks against their sites, and report back stats on a time basis.... if only there were more hours in the day!

Its ugly as sin!
If you want to pay my rent id be more then happy to spend more time on it and make it pretty. :-)

Comments to mike@blazen.com ... Paola home ... More code