Feasibility Study

The calculations  presented in the table below demonstrate that it is possible to proactively synchronize TA patron accounts and OTRBs with wireless validators.

Transit System ScaleSmall *)Medium **)Large ***)
Number of patrons (mill.)0.171.821
Max number of vehicles with validators en route1,1252,0007,500
Average number of taps/sec in peak period425408,800
Validator storage (Mbytes)606007,000
Peak data download speed (Mbit/sec)0.0150.286.9
Annual cellular data cost (thousand $/year)7.517010,000
For comparison, cellular data cost as share of revenue0.00%0.01%0.016% 

*) e.g.  Calgary, Canada

**) e.g. TTC, Toronto, Canada

***) Transport for London, UK

With a cellular plan for 20 Gbytes per month costing around $50/month or less, and wireless download speed is several megabits per sec, synchronizing validators data with the TA computer host does not seem to be an issue, even during the peak periods. The patrons move slow between transfers, and synchronization lag of several minutes can be acceptable.

We assume 20% OTRBs larger than the rider can spent in one day. These OTRBs can be synchronized with significantly slower pace or not synchronized at all. If the share of high OTRBs is larger, the load on the cellular data can be lower.