08 Nov

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: 

  1. 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
  2. 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:




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 ( showing how poor is the wireless signal performance.


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!

01 Feb

Sify broadband in rural areas


Sify is one of really interesting companies. One time pioneer of Indian internet market via chain of cyber cafes. Good old days. Present situation of Sify in consumer market is not significant. Latest earing figures clearly state company is moving towards enterprise segment.

Company is quite aggressive in enterprise segment offerings specially datacenters & corporate leased lines.
Is consumer market really over for Sify or there’s still some hope?


Well, consumer broadband market isn’t really over! Infact this is the main market which is yet to explode in India!

These are the factors which went against Sify:

  1. Company over estimated growth via Cybercafe chains. Cheap computers killed market of cyber cafe itself!
  2. Company failed to capture high end consumer segment and lost it to DSL players like BSNL/MTNL & Airtel. Quality of services was way too low (due to franchise model) adopted for distribution via last mile cable operators.
  3. Low end users were stolen by cheap wireless internet via 2G (and now 3G).
  4. Company tried using pointed wireless links when technology was very new & yet to become advance with MIMO & beam forming.
  5. Indian regulation which prohibits VoIP-PSTN connectivity again put them on back seat against main telcos like BSNL & Airtel.


Despite of these issues, I still see a huge potential for market which Sify tried to capture. Taking example of this village Radaur (where I am staying) – I can see over 20 connections to small computer shops, cell phone shops etc from Sify broadband. This is very interesting as a private broadband player is in village besides Govt. telecom player BSNL. Infact I can see lot of small shops giving priority to Sify over BSNL. I tried asking them for reason and here’s list of those:

  1. Fast installation 1-2days Vs 30+ days for BSNL.
  2. Fast fix in case of downtime – in few hours Vs 2-3 days for BSNL.
  3. No issues of breaking of cable (as in case of BSNL)


Well, these all issues are quite true. Most of these shops have subscribed to 256Kbps to 512Kbps plans and they work pretty well (as per my tests). Here Sify is using a “point to multi-point wireless network” to reach last mile. They run last mile over 60 degree sector antenna located in front of Radaur bus stand pointed towards village. Here’s the picture:



and here’s one of end user CPE antenna’s pointing towards it:




Unfortunately 1st picture isn’t clear.
It has small antenna with two parabolic antenna’s on top – one towards Yamunanagar city & other towards Ladwa village. It uses high end frequency band of 5.8Ghz which has over 40Mhz of bandwidth in free WiFi spectrum for tower backhaul. This sort of backhual works pretty well since one can get over 100Mbps for 40-50Km of distances (in this case Yamunanagar district is 20Km off from here) where they feed core network from leased fibers and run a MPLS on top of it. Though backhual capacity of such towers is quite high and for small village (with less users) – even last mile shared sector antenna too isn’t a problem. What surprises me is that – still at the end of day Sify offers similar or worst plans as compared to BSNL. Reason remains bit of backbone bandwidth costs, high amount of commission taken by middle re-sellers etc. Sify offcourse failing here to realize big market and capturing it with good marketing followed by massive deployment. At this point low end market will be again grabbed by cell phone players with 2G/3G while high end will sooner or later go to BSNL or other telcos (if last mile unbundle happens) since DSL is way more scalable then this technology apart from fact that BSNL won’t have any issue in backbone (when they have 104 pair fiber landing in village exchange!). Unless last mile unbundle happens, there’s hardly any technology which can provide wired broadband equivalent speeds for this network.


With hope for good future of broadband in India, time for me to wash my clothes! 😉