High jitter while pinging access point

Question

I need some help diagnosing temporary pauses and Internet Jitter. I'm not sure if it is a network problem, an OS issue, or something else.

My internet speed is fast, but its fluctuating, sometimes it's fast, sometimes it isn't.

When I tried pinging my access point, which is in the room next to mine, I get this:

$ ping 192.168.0.1
PING 192.168.0.1 (192.168.0.1) 56(84) bytes of data.
64 bytes from 192.168.0.1: icmp_seq=1 ttl=64 time=101 ms
64 bytes from 192.168.0.1: icmp_seq=2 ttl=64 time=2.11 ms
64 bytes from 192.168.0.1: icmp_seq=3 ttl=64 time=2.37 ms
64 bytes from 192.168.0.1: icmp_seq=5 ttl=64 time=82.9 ms
64 bytes from 192.168.0.1: icmp_seq=9 ttl=64 time=2223 ms  <<<<
64 bytes from 192.168.0.1: icmp_seq=10 ttl=64 time=1218 ms <<<<
64 bytes from 192.168.0.1: icmp_seq=11 ttl=64 time=213 ms
64 bytes from 192.168.0.1: icmp_seq=12 ttl=64 time=32.8 ms
64 bytes from 192.168.0.1: icmp_seq=15 ttl=64 time=794 ms  <<<<
64 bytes from 192.168.0.1: icmp_seq=16 ttl=64 time=1094 ms
64 bytes from 192.168.0.1: icmp_seq=17 ttl=64 time=419 ms  <<<<
64 bytes from 192.168.0.1: icmp_seq=19 ttl=64 time=1212 ms <<<<
64 bytes from 192.168.0.1: icmp_seq=20 ttl=64 time=210 ms
64 bytes from 192.168.0.1: icmp_seq=21 ttl=64 time=2.09 ms
64 bytes from 192.168.0.1: icmp_seq=22 ttl=64 time=2.96 ms
64 bytes from 192.168.0.1: icmp_seq=23 ttl=64 time=36.6 ms
64 bytes from 192.168.0.1: icmp_seq=24 ttl=64 time=2.06 ms
64 bytes from 192.168.0.1: icmp_seq=25 ttl=64 time=2.51 ms
64 bytes from 192.168.0.1: icmp_seq=26 ttl=64 time=2.07 ms
64 bytes from 192.168.0.1: icmp_seq=27 ttl=64 time=2.19 ms
64 bytes from 192.168.0.1: icmp_seq=28 ttl=64 time=3.06 ms
64 bytes from 192.168.0.1: icmp_seq=29 ttl=64 time=2.85 ms
64 bytes from 192.168.0.1: icmp_seq=30 ttl=64 time=2.60 ms
64 bytes from 192.168.0.1: icmp_seq=31 ttl=64 time=2.13 ms
64 bytes from 192.168.0.1: icmp_seq=32 ttl=64 time=2.42 ms
64 bytes from 192.168.0.1: icmp_seq=33 ttl=64 time=2.64 ms
64 bytes from 192.168.0.1: icmp_seq=34 ttl=64 time=7.68 ms
64 bytes from 192.168.0.1: icmp_seq=35 ttl=64 time=6.16 ms
64 bytes from 192.168.0.1: icmp_seq=36 ttl=64 time=3.87 ms
64 bytes from 192.168.0.1: icmp_seq=37 ttl=64 time=2.01 ms
64 bytes from 192.168.0.1: icmp_seq=38 ttl=64 time=229 ms
64 bytes from 192.168.0.1: icmp_seq=39 ttl=64 time=1390 ms <<<<
64 bytes from 192.168.0.1: icmp_seq=41 ttl=64 time=3117 ms <<<<
64 bytes from 192.168.0.1: icmp_seq=42 ttl=64 time=2113 ms <<<<
64 bytes from 192.168.0.1: icmp_seq=43 ttl=64 time=1107 ms <<<<
64 bytes from 192.168.0.1: icmp_seq=63 ttl=64 time=19.7 ms
64 bytes from 192.168.0.1: icmp_seq=64 ttl=64 time=2.94 ms
64 bytes from 192.168.0.1: icmp_seq=65 ttl=64 time=11.7 ms
64 bytes from 192.168.0.1: icmp_seq=66 ttl=64 time=13.8 ms
64 bytes from 192.168.0.1: icmp_seq=67 ttl=64 time=8.10 ms
64 bytes from 192.168.0.1: icmp_seq=68 ttl=64 time=10.0 ms
64 bytes from 192.168.0.1: icmp_seq=69 ttl=64 time=12.4 ms
64 bytes from 192.168.0.1: icmp_seq=70 ttl=64 time=8.05 ms
64 bytes from 192.168.0.1: icmp_seq=71 ttl=64 time=2.37 ms
^C
--- 192.168.0.1 ping statistics ---
71 packets transmitted, 44 received, 38% packet loss, time 70299ms
rtt min/avg/max/mdev = 2.015/357.764/3117.479/703.523 ms, pipe 4

When I tried pinging a public IP from my router, I got a steady ping delay

PING 173.194.40.180 (173.194.40.180): 56 data bytes
64 bytes from 173.194.40.180: seq=0 ttl=56 time=53.136 ms
64 bytes from 173.194.40.180: seq=1 ttl=56 time=53.256 ms
64 bytes from 173.194.40.180: seq=2 ttl=56 time=53.217 ms
64 bytes from 173.194.40.180: seq=3 ttl=56 time=53.234 ms

--- 173.194.40.180 ping statistics ---
4 packets transmitted, 4 packets received, 0% packet loss
round-trip min/avg/max = 53.136/53.210/53.256 ms

I couldn't specify the amount of packets to be pinged but I repeated the test multiple times and got similar results each time.

Is it possible that a driver issue could be causing this high jitter? (http://en.wikipedia.org/wiki/Jitter)

Answer 1

Is it possible that a driver issue could be causing this high jitter?

Is it possible this is your driver? Yes, but it's not very likely at all. Almost every time you see extremely high wireless latencies, it's a problem with noise, or signal strength (if the signal is low... say around 70dBm).

Wifi latency and packet loss are cousins of each other. 802.11 frames contain a sequence number which must be ACK'd... if the sequence number isn't ACK'd (due to loss, or a bit error in the original frame), then the sender attempts to retransmit the frame a certain number of times. These 802.11 retransmissions show up as increased latency or outright packet loss if the interference is bad enough.

I have literally seen 802.11g latency that is over 40 seconds when I'm only 50 feet from the wifi access point. That particular environment had a lot of tools that also operated in the 2.4GHz bands, so obviously the potential for errors was quite high.

Look for sources of interference on your particular wifi channel... also don't discount things like microwave ovens, or analog wireless video cameras.

if you have a wireless sniffer (open-source suggestion: Backtrack Linux LiveCD) then you can diagnose your wifi problems with Wireshark / tshark. Cisco also has a good reference for Wireshark 802.11 display filters, which help filter out noise. When you sniff wireless, remember that the channel you bind to matters... you usually won't see packets unless they're transmitted on your channel (with rare exceptions).

Answer 2

Diagnose Internet Jitter.

if you are using Windows, pingplotter is an amazing tool:

Home Page:

http://www.pingplotter.com/

Screenshot:

What could cause this

1. Malware on your computer.
2. Defective wires or contacts on network cables.
3. Defective routers or wireless access points, wireless bridges.
4. Someone on your network downloading tons of stuff on a schedule.

Steps to narrow the field of what could be causing it:

1. Use two computers to use pingplotter to see if it's hidden malware on one of the OS's.
2. Point pingplotter to your own default gateway. See if it happens there.
3. Do a traceroute between your computer and another computer on the network.
4. Connect directly to another computer on the LAN, if it happens there, install pingplotter on the other computer and scan each other.
5. Point pingplotter against a computer in the external network, like google.
6. Point pingplotter to something over a wireless network to see if that is the problem.
7. Run this program on one of your neighbor's computers that uses the same ISP, attached to his wireless, or ethernet.

In order to diagnose jitter. You need to find out where it is happening, and find out where it isn't happening. Put on your detective hat to narrow the space.

Nuclear option ideas, for when the above doesn't work

1. Install a fresh OS on the computer, eliminating viruses/malware.
2. Boot off everyone on the network but you, see if that fixes it.
3. Buy/Create a new separate but equal network. See if that bypasses the problem.
4. Move to another zipcode.