"Network and Internet technologies": HTML5 Crossword

Across

3. This type of cable transmits data along thin glass tubes. (5)
6. A type of cable which is connected to the network port. (8)
7. What should a network have in order to avoid being targeted by a user with unauthorised access? (8)
9. A HAN needs this device in order to connect the computers in a network. (6)
10. The shortened version of the device, Modulator / Demodulator. (5)
11. These IP addresses never change. (6)

Down

1. The type of connection that uses cables to connect. (0,5)
2. A USB device that acts as a small modem. (6)
4. IP addresses are allocated by this device. (6)
5. A wireless radio frequency for the transmission of data across short distances. (9)
8. These IP addresses change periodically. (7)