Measuring network performance tool in c#

Question

Dear community.

I am about to develop a Network measurement tool. The objective is to make a tool, which can measure the responsetime in between a client and a server machine (from the client side). It is s side-application to a main application - If the main applicaiton experiences that the responsetime from the server is above a certain threshold, the tool will be kicked alive, and performs network connectivity tests, to determine of the client server connection is stable (it might be unstable, due to the network being wireless etc.)

The tests I need to perform are not just ping operations, but also transmitting packages of different size.

I have however very little experience in communications technology.

Is ICMP protocol the way to go? and if yes, is it possible to send packages of differnet sizes (to measure if the network is able to transfer eg. 2 MB of data in a reasonable time)?

I have a second concern. What should I look out for in regards to firewalls? It would be a shame to develop an application which works fine on my local network, but as soon as it is used out in the real life, it fails misserably because the tests are blocked by a firewall.

I hope my questions aren't too noobish, but know that any help is much appreciated.

All the best

/Sagi

Answer 1

To keep clear of firewalls, you should do a test using the same protocol and port you use, and create inside of your application a new type of message that should be responded as soon as it is read by the server: You should program your ping measures.

Then the client would measure the times spent in travel traveled and compute your ping and relay it back to your server. This also gives a better reading when in case of some ISPs that give a ICMP protocol packets a huge advantage over other packages on their QoS server, artificially creating(faking) lower latency. And also, you would not have to worry about the firewall not allowing your ICMP packets, because you would have to be allowed to conect on the standart port you use.

Also, most games work this way (Half-Life, Age Of Empires etc.) , and not by sending standard Ping packets.