7 Written questions
6 Multiple choice questions
- transmission of frames to a subset of the machines on the broadcast network.
- - Similar to bridge in that it routes frames.
- most commonly used to connect individual computers.
- - needs to establish an end to end path before transmission.
- analogue networks.
- transmission of frames to all machines on the broadcast network.
- connects two or more LANs.
When a frame arrives, software in the bridge extracts the frame header and looks it up in a table to see where to send the frame.
- different line cards for different technologies, Ethernet, FDDI etc.
- each line has its own collision domain.
- transform raw transmission facility into a line that appears free of undetected errors to the network layer.
Accomplishes this by having the sender break up the input into frames, and transmit them sequentially. If the service is reliable, the receiver confirms the correct receipt of each frame.
6 True/False questions
WEP → data link layer protocol described by the 802.11 standard.
- uses RC4 often reuses IV.
- many installations use the same shared key for all users, so each user can read each others traffic.
- vulnerable to a number of known attacks.
Packet-switching → - chatty.
- no dedicated path required.
SSID → - based on EAP framework; negotiate authentication method at startup.
- 802.1X standard.
- uses AES
802.11a → - operates in different frequency range - 5 GHZ.
- less prone to interference.
- greater speeds.
- not as widely used.
Blue jacking (bluetooth) → Attacker can use AT commands on victims cell to initiate calls, send messages etc.
Blue tooth → - available in a range of mobile devices.
- operates in both ad-hoc mode and infrastructure mode.
- by default security is disabled but does have three security modes, ranging from full data encryption to integrity control.
- only authenticates devices, not users.
- vulnerable to buffer over flow.