Requirements

Functional Requirements:

• Allow users to browse and search available conference rooms by time slot, capacity, location (building/floor), and equipment (projector, video).
• Enable users to create, update, and cancel room bookings, including room, time, organizer, and optionally participants.
• Prevent double-booking of rooms by ensuring that concurrent booking attempts are serialized.
• Send users email or push notifications when a booking is confirmed, updated, or cancelled, and send reminder notifications before the meeting starts.
• Support user authentication and authorization with role-based access controls: regular users can book rooms, admins can manage room inventory and settings.

Non-Functional Requirements:

• Low latency: room views should be updated almost instantaneously for all users
• Scalability: needs to work for companies with different offices / locations
• Reliability: should keep the source of truth about the rooms

Capacity Estimation

Estimate the scale of the system. Consider daily active users, read/write ratio, storage requirements, bandwidth, and any relevant QPS calculations...

Suppose the company has 100k employees

20% of the users are actively using the system

5% book rooms

5k users user book rooms daily

20k users check rooms daily

writes 5k / 10^5 =0.05 users/seconds

reads 20k / 10^5 =0.2 users/seconcs

Storage:

each booking requires 10kb

5k bookings a day = 10Mb a day to store booking

suppose we keep for 10 years and we book for 2 years in advance: 12 * 365 * 10Mb = 43,800 MB about 50 GB

API Design

Define the APIs expected from the system. This is your chance to analyze and define the read and write paths so that you can come up with the high-level design...

High-Level Design

Describe the overall system architecture. Identify the main components needed to solve the problem end-to-end. Use the diagramming tool to create a block diagram.

Database Design

Define the data model. Identify the main entities, their attributes, and relationships. Consider the choice of database type (SQL vs NoSQL) and justify your decision based on access patterns...

Detailed Component Design

Deep dive into 2-3 key components. Explain how they work, how they scale, discuss tradeoffs, capacity, and any relevant algorithms or data structures.