🚆 Railways & Public Transport · C4 Architecture · Pro
Train Ticket Reservation System
A railway reservation system in the style of IRCTC: seat inventory per train and class, waitlists, Tatkal quota, payments and e-tickets.
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Drawing diagram…
What this diagram shows
- Seat inventory is locked per coach and berth during booking
- Waitlisted tickets confirm automatically when others cancel
- Tatkal booking opens at fixed times with extra load protection
Prompt used
Train reservation system: passengers book on the web and mobile app through an API gateway with a queue for Tatkal rush. The availability service answers seat availability per train, date and class from a cache. The booking service locks berths in the seat inventory, creates the PNR, and calls the payment service. The waitlist service confirms waitlisted PNRs when cancellations happen. Tickets are sent by SMS and email, and the chart preparation service finalises berths before departure.
Mermaid code
C4Container
title Train Reservation System
Person(pax, "Passenger", "Books and cancels tickets")
System_Boundary(rs, "Reservation System") {
Container(gw, "API Gateway and Queue", "NGINX + virtual waiting room", "Handles Tatkal rush")
Container(av, "Availability Service", "Java", "Seats per train, date, class")
Container(bk, "Booking Service", "Java", "PNR creation and berth locking")
Container(wl, "Waitlist Service", "Java", "Confirms on cancellation")
Container(chart, "Chart Preparation", "Batch job", "Final berth allocation")
ContainerDb(inv, "Seat Inventory", "Oracle", "Berths per coach")
ContainerDb(cache, "Availability Cache", "Redis", "Fast seat counts")
}
System_Ext(pg, "Payment Gateway", "UPI, cards, netbanking")
System_Ext(sms, "SMS and Email", "E-tickets")
Rel(pax, gw, "Books", "HTTPS")
Rel(gw, av, "Checks seats")
Rel(av, cache, "Reads")
Rel(gw, bk, "Books")
Rel(bk, inv, "Locks berths")
Rel(bk, pg, "Takes payment")
Rel(bk, sms, "Sends e-ticket")
Rel(wl, inv, "Reallocates berths")
Rel(chart, inv, "Finalises chart")Related templates
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