Smart-card validators

Smart-card validators are the devices that manage the inspection and fare collection processes for smart-cards. In the passenger transport domain, smart-card validators take one of three forms:

Stand-alone independent devices, which can carry out the transactions autonomously – i.e. they do not need to communicate with another device during the transaction (although they may receive occasional information from other devices – e.g. route number, current fare zone).
Discrete devices, which may appear to the customer to be free-standing devices (e.g. validator located at the bus entry door), but are in fact linked to a controlling device which participates directly in the transaction (e.g. a ticket-issuing machine). In this case, the validator cannot function, or cannot carry out the full range of functions, without the assistance of the other device.
Integrated devices, which are embedded in another device – e.g. smart-card validator embedded in a ticket issuing machine, fare-box and or turnstile.

Smart-card validators always incorporate a smart-card reader, which enables the communication and data exchange with the smart-card, using either contact or contactless technology. Smart-card validators always have connectors, both for data exchange with other devices and for power supply. The nature and volume of processors and memory will depend on whether the validator is an autonomous unit or whether it is a ‘slave’ for another device (e.g. a ticket-issuing machine) which controls the transactions.

The validator almost always has a display, which gives messages to the customer (e.g. fare deducted, balance remaining). It also almost always has both an audio signal and visual signals (e.g. green/orange/red LEDs) to indicate to the customer that the transaction is complete, and whether the attempted validation has been successful or rejected. Depending on the configuration, the nature of the fare products, and the options available to the user, the validator may have buttons for the user to press to select options.

In the passenger transport sector, smart-card validators (independently or in conjunction with a master device) perform some or all of the following functions:

Basic checks on whether the presented card is valid, issued by a recognized entity, initialized, authorized for use, and contains any valid fare product or travel authorization.
For travel passes, verifies that the travel pass is current, checks any applicable restrictions, approves or rejects its use, and stores or transmits transaction data for downstream processing and reimbursement.
For time-based passes, identifies applicable fare products, checks period of validity and any other restrictions, approves / rejects the transaction, and stores / transmits the transaction record.
For stored value, verifies that there is sufficient value for the transaction, allows the customer to select the required value or interfaces with the ticket-issuing machine for ticket printing, deducts the appropriate value, displays the remaining balance, and stores / transmits the transaction record to support revenue distribution.
For “tap-on, tap-off”, the validator at entry records the stage / zone of boarding. The validator at exit calculates the tariff and deducts it from the stored value. Optionally, the validator at entry may deduct the maximum applicable fare and the validator at exit refunds any unused travel value.
For journey-based tickets, the validator deducts a journey.
Where free transfers or rebates are available for stored-value or journey-based tickets, the validator determine whether the transfer conditions have been met, and then decides whether to apply free / rebate transfer or treat it as a new trip and deduct the relevant value.
For fare-capping, the validator determines whether it is applicable, and applies the appropriate rules to determine what tariff to deduct (if any).
For top-ups and re-loads, the validator acts as an interface with the ticket-issuing or vending machine where the customer makes the payment.
Where the validator is integrated with a turnstile or gate, a signal is sent to release the mechanism when the pass or payment has been approved.

Benefits of smart-card validators are:

Facilitates a wide range of inspection and fare collection functions.
Automates processes and reduces dwell time.
Facilitates integrated ticketing and transfer validation.
Assists revenue protection processes.
Collects transaction data in electronic format, both for reimbursement and for analysis.
Mature technology, well supported by international standards.

Cautions with regard to smart-card validators are:

Technical complexity, which requires a substantial level of technical competence within the organization.
Position and ergonomics of the validators is extremely important both for ease-of-use and for achieving optimal transaction and dwell times.
Cost of the devices.
Reliability, though this relates more to its external communication than the device itself.
Need to establish an effective maintenance regime.