Exam Certified Integration Architect topic 1 question 102 discussion

Northern Trail Outfitters has a registration system that is used for workshops offered at its conferences. Attendees use Salesforce Community to register for workshops, but the scheduling system manages workshop availability based on room capacity. It is expected that there will be a big surge of requests for workshop reservations when the conference schedule goes live.

Which integration pattern should be used to manage the influx in registrations?