6.10.3 Easy Connect Naming Method
The Easy Connect naming method eliminates the need to look up service names in the tnsnames.ora file or other repository for TCP/IP environments.
With Easy Connect, clients use a connect string for a simple TCP/IP address, which consists of a host name, and an optional port and service name. If you use this method, then no naming or directory system is required. See "Example 6-1" for an example.
Networking elements for the Oracle Database server and clients are preconfigured for most environments. The Easy Connect naming method is enabled by default and does not require a repository. If you use a naming method other than Easy Connect, then additional configuration of Oracle Net Services may be required.