Hailo was founded in London by three taxi drivers who saw how using smartphones to hail cabs could make the market much more efficient both for drivers and for passengers. Carl Mesner Lyons, vice president of marketing at Hailo, explains: “Hailo is a taxi magnet. Whereas before you had to go on the street and try to hail one, now with a tap of a smartphone, you can do this from your home, a restaurant, or office; taxis come to you.” Hailo launched the application in November 2011 and the company estimates that half the black cab drivers in London are registered with Hailo. Passengers can use the application to pay by credit card. The service operates in several cities across Europe, North America, and Asia, and continues to expand. Across the globe, over 32,000 drivers and close to half a million customers have signed up. There’s a Hailo hail every 4 seconds, and to date, nearly 1/2 million passengers have used the service. Hailo reports over $100 million in annualized sales.

As a start-up relying on venture capital, Hailo needed to get the service up and running as quickly as possible with minimum outlay. From the beginning, Hailo planned to expand to other cities across the globe, which means, as Mesner Lyons explains: “Because we’re growing internationally, we’re scaling both in terms of the amount of business that we generate as well as the number of locations.” In addition, as Mesner Lyons points out, Hailo needs to be responsive. “We are a real-time service, and people are saying ‘get me a taxi now’. It needs to feel as though we do that instantly.”

Hailo wanted to spend its capital wisely. Using a cloud computing platform eliminates capital outlay and allows the company to use only the computing resources that it needs rather than deploying excess capacity up front. “As a business that wishes to be lean and globally fast, Amazon Web Services (AWS) is a perfectly natural fit,” says Mesner Lyons. “Using AWS allows us to respond smartly to demand for our service that comes from a whole range of locations, where there are usage peaks at different times of day because of the time zones.”

The choice of AWS seemed equally natural to Stephen Tan, Systems Administrator. “AWS is essentially the market leader,” he says.” I’ve worked in three separate companies that have all used cloud services and they all used AWS. It’s simply the one that everyone uses”. Hailo’s entire infrastructure is hosted on AWS, which has helped the company to expand its service rapidly from Europe to North America, with plans for expansion to Asia. Tan comments, “Trying to do that with a private cloud would take considerable time. Given the business pressures and the speed with which we need to react, AWS fits perfectly.”

Hailo takes full advantage of the global footprint of AWS, deploying across three different customer zones in the US East (Northern Virginia) Region, EU (Ireland) Region, and Asia Pacific (Tokyo) Region. To maintain response speed as peak times occur in different cities across the globe, Hailo uses Amazon Route 53 Domain Name System (DNS) to connect to Amazon Elastic Compute Cloud (Amazon EC2) instances in the different Regions, and uses Elastic Load Balancing supported by the open source HAProxy to manage the loads.

Hailo’s servers run exclusively on the Ubuntu operating system, uses a Cassandra NoSQL database as its main database, a MySQL relational database, and Amazon Relational Database Service (Amazon RDS) for reporting. Tan appreciates the robust controls that AWS has in place to maintain security and data protection for the infrastructure as Hailo works to provide the Payment Card Industry (PCI) compliance essential for processing credit card transactions. Hailo is migrating to the Amazon Virtual Private Cloud (Amazon VPC), because, as Tan explains, “there are a lot of boxes within the PCI compliance requirements that we need to tick, and so we are migrating to Amazon VPC, a service that has been validated as being compliant with PCI standards.”

Tan reports that AWS Support at Enterprise-level tier is invaluable. “We are using AWS Support quite extensively now. There are some areas that we need to work through and it’s a big network.”

Hailo has been able to grow to almost half a million passengers in 11 cities in only 18 months, something that Tan believes that would not have been possible with an on-premises infrastructure or with any other cloud provider. As Mesner Lyons says, “the fact that we are serving a Hailo hail every 4 seconds around the world, and that the service is available nearly all the time is pretty good going; that is not something we expected to be able to do on day one. The fact that we have been able to grow and cope with demand is a testament to the scalability of the system we have chosen.”

For Hailo, open stacks and AWS APIs simplify the process of integrating HAProxy, Cassandra, and other tools. The ability to span different Availability Zones is essential to efficient handling of peak times as they occur in the cities that Hailo covers. “It’s trivial to spin up an instance and to scale, and that’s rich functionality,” says Tan. “When I arrived at Hailo, I had one month to implement a live service from a basic prototype. AWS databases are excellent from the development and operational point of view. That is the way we do things: infrastructure as code.”

According to Mesner Lyons, “There are opportunities for Hailo to make the taxi market work better for drivers and passengers in many more cities around the world. Everything we do, from people to systems, has to be set up to cope with that. This is the core benefit of AWS: to grow at the same speed that we can.”

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