A real-life example of a networked system
We will use the same real-life example that we have been using in previous chapters. Households in a village exchange services with each other. Each household has an isolated copy of the software that keeps the records of the contract for exchanged services.
They are suffering an ongoing problem; that is, sometimes two households that exchanged services have a discrepancy between the contract records kept in their own copy of the software. This has caused a few disputes among households.
An engineer wants to eliminate these disputes by synchronizing the contracts between two copies of the software. The synchronization requires two copies of the software to be connected. An oversimplified interaction of the synchronization is illustrated in Figure 4.1:
Figure 4.1 – Synchronization of contracts for exchanged services among households
In the diagram, Household A sends the details of the contract...