by kepler » Sat Jan 13, 2007 9:05 pm
by kepler
Sat Jan 13, 2007 9:05 pm
Hi,
inaki is right, it depends what is meant by immediate. Theoretically there is not such a thing as immediate in communication.
To be more precise I just made couple of simple ping tests between two Internet tablets with WLAN connection. These tests don’t of course tell the whole story but gives idea about the order of magnitude.
Test case 1: 64 bytes packets were pinged 142 times between 2 Internet tablets which were connected with WLAN ad hoc connection to each other. So each packet was going WLAN connection twice. And results were:
Test time 141085 ms, rtt (round trip time) min/avg/max/mdev = 3.235/6.014/22.064/2.312 ms
Test case 2: 64 bytes packets were pinged 143 times between Internet tablet and access point (Linksys). So each packet was going WLAN connection twice. And results were:
Test time 142159 ms, rtt min/avg/max/mdev = 1.770/3.378/69.062/6.251 ms
Test case 3: 64 bytes packets were pinged 146 times between two Internet tablets which were connected via access point (Linksys). So each packet was going WLAN connection four times. And results were:
Test time 145021 ms, rtt min/avg/max/mdev = 3.479/5.516/46.966/3.725 ms
Surprisingly the ad hoc connection was the slowest. So is it fast enough depends fully on requirements. Bluetooth connection is slower so it will take longer time, but it also depends on packet length and used protocol what is achieved. As such radio waves transmit on speed of light in both radios
So radio connection speed always depends, it’s always far from immediate but definitely much more far from few seconds (as was asked in original question).
-kepler
Hi,
inaki is right, it depends what is meant by immediate. Theoretically there is not such a thing as immediate in communication.
To be more precise I just made couple of simple ping tests between two Internet tablets with WLAN connection. These tests don’t of course tell the whole story but gives idea about the order of magnitude.
Test case 1: 64 bytes packets were pinged 142 times between 2 Internet tablets which were connected with WLAN ad hoc connection to each other. So each packet was going WLAN connection twice. And results were:
Test time 141085 ms, rtt (round trip time) min/avg/max/mdev = 3.235/6.014/22.064/2.312 ms
Test case 2: 64 bytes packets were pinged 143 times between Internet tablet and access point (Linksys). So each packet was going WLAN connection twice. And results were:
Test time 142159 ms, rtt min/avg/max/mdev = 1.770/3.378/69.062/6.251 ms
Test case 3: 64 bytes packets were pinged 146 times between two Internet tablets which were connected via access point (Linksys). So each packet was going WLAN connection four times. And results were:
Test time 145021 ms, rtt min/avg/max/mdev = 3.479/5.516/46.966/3.725 ms
Surprisingly the ad hoc connection was the slowest. So is it fast enough depends fully on requirements. Bluetooth connection is slower so it will take longer time, but it also depends on packet length and used protocol what is achieved. As such radio waves transmit on speed of light in both radios
So radio connection speed always depends, it’s always far from immediate but definitely much more far from few seconds (as was asked in original question).
-kepler