Excessive broadcasts, however, consume network bandwidth and CPU cycles. Neither hubs nor LAN switches isolate broadcasts. Therefore, all devices connected to a switched network are said to be part of the same broadcast domain.
Every device sees the broadcast and interprets it to see if any action is required.
In practice, however, it is always preferable to locate the application servers as close as possible to the database server to make optimum use of network resources. Traffic between desktop clients and application servers is much lighter than between application servers and the database server. Through collocation, the application servers and database server can communicate at high speed over a data center connection, ensuring optimum performance. Oracle and Cisco recommend 100-Mbps connections, such as those provided by switched Fast Ethernet. Oracle clients receive dedicated 10-Mbps bandwidth with the Catalyst 1900 switch.