Querying the ledger

The simplest operation an application can perform is to query a ledger. Let's examine how the registration and trading applications query a ledger in different networks:

Figure 7.10: The simplest operation an application can perform is to query a ledger

In Figure 7.10, we can see that peer1 has the registration contract installed, making it available to all applications connected to the vehicle-registration network. Similarly, Peer1 also has car contract installed for participants in the car-trading network. The registration application uses the registration contract to query the registration ledger, and the car contract to query the trading ledger.

But where are the registration and car ledgers in Figure 7.10? Let's take a closer look at the smart contracts to find out.

Smart contract packaging and namespaces

Smart contracts are placed in a package for both logical grouping and distribution. Consider an example:

Figure...