The Hunt for Bangalore’s Fastest Mobile Data Network
At the Fastah Project, we map India’s mobile internet and WiFi. Using crowd-sourced data from tens of thousands of smartphones around the country, we measure the performance of mobile data networks. For this first post in a series, we compare the three leading 3G and 4G providers in Bangalore in terms of their “speed”.
But what exactly do we mean by speed?
The Yardsticks
For the purpose of this post, we use two metrics to objectively assess the “speed”, or more specifically, the quality of service delivered by these networks: latency and packet loss.
Latency is the time taken for a packet of information, i.e. a string of bits containing a message, to travel from source to destination through the communication channel. Round Trip Time (RTT), also known as ping time, is the time taken by a data packet to go from source to destination and back. Ping times, measured in milliseconds (ms), are a direct measure of the system latency. The higher the latency, the slower the network.
Packet Loss is the fraction of data packets lost en route to a server or a device. The higher the packet loss, the more lethargic your mobile internet experience becomes, as information has to be transmitted again.
Why Does Speed Matter?
The speed of the network greatly affects user experience. The common wisdom is that 0.1 seconds is the response time limit for a perceived real-time interaction and 10 seconds the upper limit for holding a user’s attention. The role of seamless user experience in customer engagement, retention and conversion for online businesses and financial market deals has lead to ever increasing efforts to push these latency numbers.
The Contenders: Mobile Networks in Bangalore
We chose to compare Airtel, Jio and Vodafone as they are the most widely used mobile networks in Bangalore at the moment. In this data set, collected over November and December 2016, we have 35,063 samples from Airtel, 13,051 from Jio and 6538 from Vodafone. We did not select these users by hand — the varying sample size is a natural consequence of the differing popularity of these network providers in the city.
How We Do It : Measuring Performance
At regular intervals throughout the day, sets of twenty data packets are sent out from Android smartphones affiliated to the Fastah Project. This is referred to as a “ping”. We record the time taken for the ping to go from a phone to our server (hosted with Microsoft Azure in Mumbai) and back. There are several stops on this round trip journey, but for now we only examine the total time taken. For our present analysis, we only compare the average values of round trip times measured during weekdays (Monday to Friday) in November and December of 2016, over the whole of Bangalore, including its suburbs.
What We Saw: Latency
We wanted to find out how the performance of each of the networks varies over a typical work day. We were interested to see if there is a correlation with peak morning and evening rush hours. We plotted the mean value of round trip times (averaged over November and December) against time of day.
The new 4G kid on the block, Jio by Reliance displays the lowest latency throughout the day. This is as expected as it deploys a legacy-free 4G only network and still has fewer subscribers than the incumbents.
We observed that Airtel has the highest average latency, which further peaks during busy evening hours. This is mainly due to the fact that Airtel has the largest subscriber base in Bangalore, which tends to overload their infrastructure. Moreover, over 75% of our Airtel samples were on 3G, which pulls up its average round trip time, as compared to 4G-only Jio.
Vodafone shows significantly better latency than Airtel and only marginally worse than Jio. This may be because of Vodafone’s smaller subscriber base for 3G and 4G services in Bangalore.
What We Saw: Packet Loss
Like latency, the fraction of packets lost increases with the number of users competing for internet access. About 95% of the time in the data collected, no packets were lost. However, for some pings, say 2 of 20 packets are lost, or 10 of 20 packets are lost, which correspond to a 20% or 50% packet loss respectively. The density distribution below shows the fraction of pings which suffer from different percentages of packet loss. For example, for Vodafone, 0.01 of its pings suffer from 50% packet loss. Bear in mind that in the graph, we have excluded the cases for which packet loss was less than 10%.
The packet loss distribution looks similar for all three networks. Airtel’s performance is slightly worse than Vodafone and Jio, in this regard.
And The Winner Is…
In sheer latency numbers, Jio holds the title. However, it has the advantage of being a pure 4G network. Between the other two, Vodafone has lower latency. We will continue exploring other parameters and networks in posts to come!
If you’d like to contribute to our research or have a question, please leave a comment below. You can also write to us at research@getfastah.com.
