Why airport wifi sucks?
Sitting at Kolkata airport. Noticed the usual “Free Wifi in the area!” message and connected to Tata Docomo Free wifi. Performance was quite poor.
Two key issues with wifi:
- Using of only 2.4Ghz (802.11b/g/n with 20Mhz channel). No AP with 5Ghz box. (Click here to view scanner data). Should have been 5Ghz
- Entire traffic is getting tunnel via Mumbai i.e West India (while I am sitting on Eastern side). Adding up to latency and performance significantly.
Here are some of traces to random locations:
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traceroute anuragbhatia.com traceroute to anuragbhatia.com (178.238.225.14), 64 hops max, 52 byte packets 1 100.96.128.1 (100.96.128.1) 74.141 ms 55.771 ms 83.987 ms 2 10.124.109.130 (10.124.109.130) 60.473 ms 56.363 ms 56.885 ms 3 * 10.124.111.158 (10.124.111.158) 57.123 ms 60.577 ms 4 10.117.225.90 (10.117.225.90) 62.529 ms 57.420 ms 57.032 ms 5 14.141.63.185.static-mumbai.vsnl.net.in (14.141.63.185) 57.206 ms 57.201 ms 59.841 ms 6 * * * 7 ix-0-100.tcore1.mlv-mumbai.as6453.net (180.87.38.5) 60.127 ms * 59.179 ms 8 if-9-5.tcore1.wyn-marseille.as6453.net (80.231.217.17) 163.571 ms 163.083 ms 165.671 ms 9 if-8-1600.tcore1.pye-paris.as6453.net (80.231.217.6) 165.586 ms * 168.976 ms 10 if-2-2.tcore1.pvu-paris.as6453.net (80.231.154.17) 164.356 ms 160.600 ms 167.841 ms 11 80.231.153.66 (80.231.153.66) 204.567 ms 170.125 ms 164.025 ms 12 ae-1-19.bar1.munich1.level3.net (4.69.153.245) 187.130 ms 176.954 ms 175.734 ms 13 ae-1-19.bar1.munich1.level3.net (4.69.153.245) 173.793 ms 180.293 ms 175.585 ms 14 gw03.contabo.net (62.140.24.126) 174.955 ms * * 15 anuragbhatia.com (178.238.225.14) 179.955 ms * 179.185 ms |
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traceroute google.com traceroute: Warning: google.com has multiple addresses; using 173.194.36.97 traceroute to google.com (173.194.36.97), 64 hops max, 52 byte packets 1 100.96.128.1 (100.96.128.1) 57.058 ms 56.659 ms 55.847 ms 2 10.124.109.130 (10.124.109.130) 56.825 ms 58.513 ms 55.854 ms 3 10.124.111.158 (10.124.111.158) 56.682 ms 60.542 ms 59.486 ms 4 10.117.225.90 (10.117.225.90) 58.176 ms 57.624 ms 58.444 ms 5 14.141.63.185.static-mumbai.vsnl.net.in (14.141.63.185) 58.806 ms 57.714 ms 59.340 ms 6 * * * 7 115.113.165.98.static-mumbai.vsnl.net.in (115.113.165.98) 58.810 ms 65.872 ms 69.436 ms 8 209.85.241.52 (209.85.241.52) 58.748 ms 60.547 ms 72.14.232.202 (72.14.232.202) 58.878 ms 9 209.85.252.142 (209.85.252.142) 77.188 ms 80.828 ms 78.031 ms 10 209.85.240.17 (209.85.240.17) 82.458 ms 77.529 ms 79.603 ms 11 del01s07-in-f1.1e100.net (173.194.36.97) 77.242 ms * 76.067 ms |
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traceroute cloudaccess.net traceroute to cloudaccess.net (199.116.78.60), 64 hops max, 52 byte packets 1 100.96.128.1 (100.96.128.1) 65.006 ms 73.056 ms 57.290 ms 2 * 10.124.109.130 (10.124.109.130) 55.313 ms 55.498 ms 3 10.124.111.158 (10.124.111.158) 62.335 ms 58.146 ms 65.322 ms 4 10.117.225.90 (10.117.225.90) 58.307 ms 64.118 ms 60.188 ms 5 14.141.63.185.static-mumbai.vsnl.net.in (14.141.63.185) 67.951 ms 58.059 ms 57.658 ms 6 * * * 7 ix-0-100.tcore1.mlv-mumbai.as6453.net (180.87.38.5) 60.601 ms 58.711 ms 58.611 ms 8 if-9-5.tcore1.wyn-marseille.as6453.net (80.231.217.17) 170.234 ms 163.890 ms * 9 if-8-1600.tcore1.pye-paris.as6453.net (80.231.217.6) 163.956 ms 165.691 ms 174.445 ms 10 if-2-2.tcore1.pvu-paris.as6453.net (80.231.154.17) 161.027 ms 165.970 ms 179.712 ms 11 80.231.153.202 (80.231.153.202) 164.602 ms 164.395 ms 163.093 ms 12 xe-1-2-2.chi11.ip4.gtt.net (89.149.187.85) 271.367 ms xe-8-2-2.chi11.ip4.gtt.net (141.136.105.253) 273.996 ms 265.810 ms 13 ip4.gtt.net (173.205.48.130) 266.941 ms 265.019 ms 265.221 ms 14 173-225-176-89.core2.sfld2.r256.net (173.225.176.89) 275.479 ms 272.507 ms 272.840 ms 15 border-router02-detroit.static.cloudaccess.net (173.225.188.138) 280.231 ms 268.907 ms 286.357 ms 16 199.116.78.60 (199.116.78.60) 269.869 ms !Z 270.031 ms !Z 270.207 ms !Z |
So no matter wherever I push packets for, then hit hop 5 – Mumbai / VSNL AS4755 router because likely that is where the core L3 device (MSC/central authentication box) for this network is. This is big issue because likely Tata Docomo would be tunneling entire wifi traffic from anywhere in India, going to anywhere globally via Mumbai because that is where they put their wifi central box. What we need in India is more simpler deployments, more open source stuff so cost doesn’t becomes point of selection for keeping such devices central. And most important we need networks to peer at internet exchanges so atleast East region traffic stays within East and doesn’t has to travel thousands of kilometers to Mumbai just to hop on to another network.
Overall speeds seems to be capped at 1Mbps which is too low these days and here’s 100 packet ping to first hop (100.96.128.1) showing how poor is the wireless signal performance.
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ping -c 100 100.96.128.1 PING 100.96.128.1 (100.96.128.1): 56 data bytes 64 bytes from 100.96.128.1: icmp_seq=0 ttl=255 time=52.365 ms 64 bytes from 100.96.128.1: icmp_seq=1 ttl=255 time=51.391 ms 64 bytes from 100.96.128.1: icmp_seq=2 ttl=255 time=48.985 ms 64 bytes from 100.96.128.1: icmp_seq=3 ttl=255 time=264.974 ms 64 bytes from 100.96.128.1: icmp_seq=4 ttl=255 time=252.179 ms Request timeout for icmp_seq 5 64 bytes from 100.96.128.1: icmp_seq=6 ttl=255 time=51.491 ms 64 bytes from 100.96.128.1: icmp_seq=7 ttl=255 time=81.809 ms 64 bytes from 100.96.128.1: icmp_seq=8 ttl=255 time=49.312 ms 64 bytes from 100.96.128.1: icmp_seq=9 ttl=255 time=55.065 ms 64 bytes from 100.96.128.1: icmp_seq=10 ttl=255 time=52.825 ms 64 bytes from 100.96.128.1: icmp_seq=11 ttl=255 time=49.899 ms 64 bytes from 100.96.128.1: icmp_seq=12 ttl=255 time=59.585 ms 64 bytes from 100.96.128.1: icmp_seq=13 ttl=255 time=262.916 ms 64 bytes from 100.96.128.1: icmp_seq=14 ttl=255 time=55.734 ms 64 bytes from 100.96.128.1: icmp_seq=15 ttl=255 time=49.476 ms 64 bytes from 100.96.128.1: icmp_seq=16 ttl=255 time=48.953 ms Request timeout for icmp_seq 17 64 bytes from 100.96.128.1: icmp_seq=18 ttl=255 time=299.531 ms 64 bytes from 100.96.128.1: icmp_seq=19 ttl=255 time=315.367 ms 64 bytes from 100.96.128.1: icmp_seq=20 ttl=255 time=49.276 ms 64 bytes from 100.96.128.1: icmp_seq=21 ttl=255 time=48.629 ms 64 bytes from 100.96.128.1: icmp_seq=22 ttl=255 time=59.231 ms 64 bytes from 100.96.128.1: icmp_seq=23 ttl=255 time=54.367 ms 64 bytes from 100.96.128.1: icmp_seq=24 ttl=255 time=49.607 ms 64 bytes from 100.96.128.1: icmp_seq=25 ttl=255 time=62.368 ms 64 bytes from 100.96.128.1: icmp_seq=26 ttl=255 time=50.263 ms 64 bytes from 100.96.128.1: icmp_seq=27 ttl=255 time=167.378 ms Request timeout for icmp_seq 28 64 bytes from 100.96.128.1: icmp_seq=29 ttl=255 time=316.048 ms 64 bytes from 100.96.128.1: icmp_seq=30 ttl=255 time=325.624 ms 64 bytes from 100.96.128.1: icmp_seq=31 ttl=255 time=463.967 ms 64 bytes from 100.96.128.1: icmp_seq=32 ttl=255 time=469.114 ms 64 bytes from 100.96.128.1: icmp_seq=33 ttl=255 time=292.147 ms 64 bytes from 100.96.128.1: icmp_seq=34 ttl=255 time=522.468 ms 64 bytes from 100.96.128.1: icmp_seq=35 ttl=255 time=713.133 ms 64 bytes from 100.96.128.1: icmp_seq=36 ttl=255 time=110.451 ms Request timeout for icmp_seq 37 64 bytes from 100.96.128.1: icmp_seq=38 ttl=255 time=342.196 ms Request timeout for icmp_seq 39 64 bytes from 100.96.128.1: icmp_seq=40 ttl=255 time=269.410 ms 64 bytes from 100.96.128.1: icmp_seq=41 ttl=255 time=252.759 ms 64 bytes from 100.96.128.1: icmp_seq=42 ttl=255 time=406.372 ms 64 bytes from 100.96.128.1: icmp_seq=43 ttl=255 time=222.788 ms 64 bytes from 100.96.128.1: icmp_seq=44 ttl=255 time=228.961 ms 64 bytes from 100.96.128.1: icmp_seq=45 ttl=255 time=205.769 ms 64 bytes from 100.96.128.1: icmp_seq=46 ttl=255 time=177.845 ms Request timeout for icmp_seq 47 64 bytes from 100.96.128.1: icmp_seq=48 ttl=255 time=347.503 ms 64 bytes from 100.96.128.1: icmp_seq=49 ttl=255 time=285.772 ms 64 bytes from 100.96.128.1: icmp_seq=50 ttl=255 time=428.171 ms 64 bytes from 100.96.128.1: icmp_seq=51 ttl=255 time=306.871 ms 64 bytes from 100.96.128.1: icmp_seq=52 ttl=255 time=246.806 ms 64 bytes from 100.96.128.1: icmp_seq=53 ttl=255 time=213.304 ms 64 bytes from 100.96.128.1: icmp_seq=54 ttl=255 time=175.060 ms 64 bytes from 100.96.128.1: icmp_seq=55 ttl=255 time=262.179 ms 64 bytes from 100.96.128.1: icmp_seq=56 ttl=255 time=421.965 ms 64 bytes from 100.96.128.1: icmp_seq=57 ttl=255 time=339.597 ms 64 bytes from 100.96.128.1: icmp_seq=58 ttl=255 time=334.415 ms 64 bytes from 100.96.128.1: icmp_seq=59 ttl=255 time=461.400 ms 64 bytes from 100.96.128.1: icmp_seq=60 ttl=255 time=439.854 ms 64 bytes from 100.96.128.1: icmp_seq=61 ttl=255 time=475.714 ms 64 bytes from 100.96.128.1: icmp_seq=62 ttl=255 time=269.855 ms 64 bytes from 100.96.128.1: icmp_seq=63 ttl=255 time=223.720 ms 64 bytes from 100.96.128.1: icmp_seq=64 ttl=255 time=190.660 ms 64 bytes from 100.96.128.1: icmp_seq=65 ttl=255 time=70.555 ms 64 bytes from 100.96.128.1: icmp_seq=66 ttl=255 time=51.592 ms 64 bytes from 100.96.128.1: icmp_seq=67 ttl=255 time=57.906 ms 64 bytes from 100.96.128.1: icmp_seq=68 ttl=255 time=54.205 ms 64 bytes from 100.96.128.1: icmp_seq=69 ttl=255 time=250.238 ms 64 bytes from 100.96.128.1: icmp_seq=70 ttl=255 time=62.416 ms 64 bytes from 100.96.128.1: icmp_seq=71 ttl=255 time=51.538 ms 64 bytes from 100.96.128.1: icmp_seq=72 ttl=255 time=48.953 ms 64 bytes from 100.96.128.1: icmp_seq=73 ttl=255 time=193.173 ms 64 bytes from 100.96.128.1: icmp_seq=74 ttl=255 time=183.505 ms 64 bytes from 100.96.128.1: icmp_seq=75 ttl=255 time=371.035 ms 64 bytes from 100.96.128.1: icmp_seq=76 ttl=255 time=77.897 ms 64 bytes from 100.96.128.1: icmp_seq=77 ttl=255 time=51.497 ms 64 bytes from 100.96.128.1: icmp_seq=78 ttl=255 time=54.808 ms Request timeout for icmp_seq 79 64 bytes from 100.96.128.1: icmp_seq=80 ttl=255 time=60.320 ms 64 bytes from 100.96.128.1: icmp_seq=81 ttl=255 time=48.887 ms 64 bytes from 100.96.128.1: icmp_seq=82 ttl=255 time=49.610 ms Request timeout for icmp_seq 83 64 bytes from 100.96.128.1: icmp_seq=84 ttl=255 time=51.179 ms 64 bytes from 100.96.128.1: icmp_seq=85 ttl=255 time=64.214 ms 64 bytes from 100.96.128.1: icmp_seq=86 ttl=255 time=64.161 ms 64 bytes from 100.96.128.1: icmp_seq=87 ttl=255 time=168.550 ms 64 bytes from 100.96.128.1: icmp_seq=88 ttl=255 time=163.238 ms 64 bytes from 100.96.128.1: icmp_seq=89 ttl=255 time=164.712 ms 64 bytes from 100.96.128.1: icmp_seq=90 ttl=255 time=62.995 ms 64 bytes from 100.96.128.1: icmp_seq=91 ttl=255 time=65.484 ms 64 bytes from 100.96.128.1: icmp_seq=92 ttl=255 time=50.530 ms 64 bytes from 100.96.128.1: icmp_seq=93 ttl=255 time=54.615 ms Request timeout for icmp_seq 94 64 bytes from 100.96.128.1: icmp_seq=95 ttl=255 time=57.349 ms 64 bytes from 100.96.128.1: icmp_seq=96 ttl=255 time=59.677 ms 64 bytes from 100.96.128.1: icmp_seq=97 ttl=255 time=191.897 ms 64 bytes from 100.96.128.1: icmp_seq=98 ttl=255 time=49.441 ms --- 100.96.128.1 ping statistics --- 100 packets transmitted, 90 packets received, 10.0% packet loss round-trip min/avg/max/stddev = 48.629/182.123/713.133/147.560 ms |
Since latency min is 48ms, quite clearly L3 end is far off in Mumbai and likely would be running ipsec or some other kind of VPN tunnels to the APs. This is ground level performance of what we hear in media “wifi business strategies“. Wifi as a technology is excellent but does take decent homework to deploy properly. Just hanging bunch of boxes and routing traffic from one MSC/central server placed far off doesn’t really helps. Wifi as a technology can help to offload stress on 3G/4G significantly as long as it is done in right way keeping in assumption that Wifi runs on “unlicensed spectrum” and interference can very much happen.
Time to catch up flight to next hop!