Segmentation of a data stream happens at which layer of the OSI model?

Which layer 1 devices can be used to enlarge the area covered by a single LAN segment?
1. Switch
2. NIC
3. Hub
4. Repeater
5. RJ45 transceiver

A. 1 only

B. 1 and 3

C. 3 and 4

D. 5 only

E. All of the above

Routers operate at layer _____. LAN switches operate at layer _____. Ethernet hubs operate at layer _____. Word processing operates at layer _____.

A. 3, 3, 1, 7

B. 3, 2, 1, none

C. 3, 2, 1, 7

D. 3, 3, 2, none

E. All of the above

Which of the following describe router functions?

A. Packet switching

B. Packet filtering

C. Internetwork communication

D. Path selection

E. All of the above

Why does the data communication industry use the layered OSI reference model?
1. It divides the network communication process into smaller and simpler components, thus aiding component development, design, and troubleshooting.
2. It enables equipment from different vendors to use the same electronic components, thus saving research and development funds.
3. It supports the evolution of multiple competing standards and thus provides business opportunities for equipment manufacturers.
4. It encourages industry standardization by defining what functions occur at each layer of the model.

A. 1 only

B. 1 and 4

C. 2 and 3

D. 3 only