Hi
Measure latency can be very hard or very easy depending on your requirements.
if you need to find out the absolute latency with the different types of delay that will be very hard.
If you are just out to find out the aproximate latency for the line it is very easy.
if you setup a computer with wireshark and ping something at the other end while you are recording.
that will give you a good estimate on what timing you have over the link.
however that will give you the processing latency of the unit on the other end.
if you want to remove that out of the equation you will have to setup a second wireshark on the other end that captures the packets.
that will give you the inbound icmp time and the outbound icmp time and you can remove that time from the total time from the computer that pings and divide the total with two. that will give you a rough aproximate of the real time it takes to send a packet over the link.
do this several times and take out an average.
There are several error factors not taken into consideration when you do it this way but its cheap, easy and gives a "good" guestimate.
if you need more accuracy to check for fx jitter you need to use special software
examples of software that can help you would be
PRTG
IXCHARIOT
and if you need to do point point checking for Highspeed trading networks and so on then there are yet some stuff you can do but they start to become quite costly.
Good luck
HTH
