Kam: Quite a bit, mostly in terms of customer behavior. With some contactless transactions, the user only places the card on the reader for a short period of time--there's no one to monitor how long they keep it there until the transaction is completed. So in our technology design we must cater to this situation. We have to provide not only the technology but the operational experience to handle these different scenarios.

CWHK: What have you learned about typical transaction times?

Kam: For transport transactions--like going through an MTR gate--our standard is 0.3 seconds. For retail, we can allow a bit more time: one second.

Right now, our card-readers are based on Sony technology and we have about 50,000 throughout Hong Kong. But we have been working on a new model for the last two years that will eventually replace all the readers in the field.

The new reader is developed by Octopus engineers in Hong Kong, and runs on an embedded Linux OS. It can accept one or more SIM cards, which will allow it to read cards issued in China, Shenzhen, etc. All the security and encryption keys will be embedded in the [reader's] SIM cards, so we don't have to worry about disclosing sensitive information to other parties.