سوال ۲۰ کنکور ارشد علوم کامپیوتر ۱۴۰۰

PASSAGE 1: ADDRESSING (excerpt)

In the branched-network case, including all hierarchical network, it is necessary (to avoid line congestion due to message broadcasting over all lines) for the switch to be able to determine the proper physical route for the message. Since this requires a prior knowledge of the physical address, the switch must contain a current mapping of logical-to-physical addresses or restrict the network to physical addressing. In essence, logical addressing in branched and hierarchical networks implies a network manager and greatly increases the control complexity of the network. Nevertheless, it is anticipated that some form of a network or subnetwork manager will be employed in many instances, even in the absence of logical (virtual) message addressing.

According to the passage, a network manager ----------.

1. complicates the control process
2. removes the need for logical addressing
3. enforces the use of logical addressing
4. may be used, regardless of logical addressing