How to practically measure end to end delay

Question

So i have 5 nodes A,B,C,D,E. A client, E server, rest are routers, and i would like to measure end to end delay between A and E. The only solution i can come up with is taking a time stamp in A, putting it in header, taking another time stamp at E when it recieves the packet and substract the client time stamp from server's.

Is there any more scientific way that i am not aware of?

I can sum processing delay+4*tranmission delay but i need to compute it, can't use theoretical work.

Thanks in advance. I also see there is no delay related tag, interesting.

Answer 1

The most accurate way that I can think of to measure round-trip network time between two TCP/IP endpoints is to capture network traffic using taps on the network interfaces of each, and use a large unidirectional TCP data transfer. This will show you the time taken for each endpoint to ack data and will also give you the round time to ack across the network. Take one from the other and you get a figure that is order-of-magnitude accurate to the resolution of the capture device and any tap delay.

Other non-IP protocols will probably have similar techniques available if TCP/IP is not your bag.

Measuring one-way delay is harder becuse you need to get very accurate time synchonisation between the timing devices at each end.

Answer 2

Not sure if IP SLA applies, from what I've read it is used to measure network performance, could solve your issue

Answer 3

You can use ping to measure round-trip times. Under the assumption that the network delays in both direction are symmetric, you can divide by two, possibly after subtracting estimated processing delays. For asymmetric-delay networks, this will not work and there is no way to measure just one trip using the network only (without an external clock synchronization system). See this great answer.

I don't think there is a standard tool to measure round-trip times other than ping. Of course it is possible to do so with other protocols instead of ICMP which ping uses (like TCP), but you will have trouble finding tools to do so.

Answer 4

Capture TCP dump on souce or destination servers and extract TCP dump in wire shark .This wiresshark logs can clearly demonstrate the TCP handshake total round trip time . Or there is a clear visibility on traffic from source to destination and destination to source vice-versa along with timestamp from this observation delays or latency at network level can be analysed.