From the Oracle9i Net Services administrator's guide:
"Clients can connect to a server using host naming if the following conditions are
met:
Oracle Net Services software installed on both the client and database service
Oracle TCP/IP protocol support on both the client and database service
An IP address translation mechanism, such as Domain Name System (DNS) or
centrally maintained TCP/IP hosts file, to resolve names
No advanced features like Oracle Connection Manager or security are
requested or required"