UniTiAg Business Architecture

Let’s take a closer look at the business architecture of UniTiAg. 



It is a two-sided marketplace, for TAs as e-merchants and their riders as shoppers.  It reconciles the participating TAs for fares charged, up to the OTRB.  UniTiAg communicates with the payment schemes to provide OTRB top-up and refund services to riders via CNP transactions. 

The OTRB is shared between the participating TAs. UniTiAg synchronizes the OTRB list with the TAs in near real-time. When some of the funds on the OTRB is spent in one TA, another TA will see the OTRB decrease by the time the rider reaches any validator of that TA. 

The OTRB can be pre-authorized, prepaid, postpaid, or a combination of thereof, depending on the UniTiAg customer’s creditworthiness, types of payment cards associated with the OTRB, and UniTiAg risk management policies.  

Transit Agency

Transit Agency is a transit operator or an agency representing several transit operators. The TA acts as a merchant from the UniTiAg’s standpoint.

The TA: 

  • implements its access (validation) policies and determines fares,   
  • collects proofs of service in the form of contactless card tap data,  
  • maintains unique relations with the riders regarding fare policies and services, 
  • optionally, maintains unique ABT system with rider profiles comprising ride history, discounts, and concession parameters, 
  • implements UniTiAg API for OTRB lists synchronization, fare charge and refunds reporting, and fare reconciliation. 
  • The TA is not required to implement any type of acquiring for fare collection purposes. The TA does not need to be PCI DSS compliant unless it decides to keep some sensitive cardholder information (for example, to implement their concession policies).  

UniTiAg maintains a large OTRB list but only synchronizes with TAs the OTRBs actively used there. 


Validators belong to their respective TAs and are managed by them through the TAs proprietary APIs. There are two types of validators: 

  • Wireless Validators which are usually installed on transit vehicles. They can also be hand-held devices used to validate trips and collect fares. Such validators require a copy of OTRB list that their TA provides them with and synchronizes periodically. 
  • Wired Validators which are usually installed on railway or subway stations, or in any sites where internet connection is reliable and fast. Such validators do not need their own copies of OTRB lists because they can always access the OTRB data or even get validation decisions fast enough, directly from their TA. 

Next to read

UniTiAg contractual relations with customers

Business Artifacts

Feasibility study