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IT technical memo of networking

Trends of Ping response time to Tokyo in a move by Shinkansen from Sendai to Tokyo

f:id:daichi703n:20160923144406j:plain

One of the tools of network engineers, Ping. Ping is used in network reachability validation to the target device, in it, Ping response time (Latency) from the target device is also included. When the Ping response delay (Latency) is increased, communication but itself can, slow page display, will become useless.

When riding the bullet train from Sendai to Tokyo, the radio wave is poor when it comes to the mountainous region, often interfere with communication. Suddenly, to Tokyo from all over to be passed in the Shinkansen, will it take how much of the communication time? When riding the bullet train from Sendai to Tokyo, the radio wave is poor when it comes to the mountainous region, often interfere with communication. Suddenly, to Tokyo from all over to be passed in the Shinkansen, will it take how much of the communication time? So was worrisome and, continue to Ping during riding a bullet train, I tried to measure the response time.

Ping execution environment

To run a continuous Ping in the following environments and conditions.

Ping execution result

crosh> ping 220.147.xxx.xxx -s 1000
PING 220.147.xxx.xxx 1000(1028) bytes of data.
1008 bytes from 220.147.xxx.xxx: icmp_seq=1 ttl=240 time=141 ms
1008 bytes from 220.147.xxx.xxx: icmp_seq=2 ttl=240 time=467 ms
1008 bytes from 220.147.xxx.xxx: icmp_seq=3 ttl=240 time=518 ms
1008 bytes from 220.147.xxx.xxx: icmp_seq=4 ttl=240 time=1062 ms
...

As it follows to the transition of the Ping response time in the graph.

f:id:daichi703n:20160923142503p:plain

It should be noted that, due to the start of the Ping run from Miyagi prefecture south, the left is not strictly in Sendai. The right to stop the Ping at the Tokyo Station arrival.

Ping: 2796 times drop: 67 times

Ping response shortest: 78.7msec Ping response maximum: 10876msec

2796 times / 60 seconds = 46.6 minutes

I feel a little short to think, but generally the time that had hit the Ping in the bullet train and was about that.

Unfortunately, we were expecting, a result that the Ping response becomes faster as it approaches the Tokyo was not obtained...
What surprised me was the thing that Ping response came back with more than a few seconds. Probably it has been buffered by the router on the path.

Conclusion

While moving in a bullet train from Sendai to Tokyo, it was continued measuring the Ping response time of up to Tokyo in Softbank (iPhone tethering) access. Unfortunately, we were expecting, a result that the Ping response becomes faster as it approaches the Tokyo was not obtained...
I think to try to similar measurements even at the time of long-range transport in the future.


This Blog is English Version of my JP's.

Sorry if my English sentences are incorrect.

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