Domain 4: Communication and Network Security

#1 Q: What are the two sublayers of Layer 2, and what are two IEEE standards that describe technologies at that layer?

A: The data link layer, or Layer 2, of the OSI model is responsible for adding a header and a trailer to a packet to prepare the packet for the local area network or wide area network technology binary format for proper line transmission. Layer 2 is divided into two functional sublayers. The upper sublayer is the Logical Link Control (LLC) and is defined in the IEEE 802.2 specification. It communicates with the network layer, which is immediately above the data link layer. Below the LLC is the Media Access Control (MAC) sublayer, which specifies the interface with the protocol requirements of the physical layer. Thus, the specification for this layer depends on the technology of the physical layer. The IEEE MAC specification for Ethernet is 802.3, Token Ring is 802.5, wireless LAN is 802.11, and so on. When you see a reference to an IEEE standard, such as 802.11 or 802.16, it refers to the protocol working at the MAC sublayer of the data link layer of the protocol stack. Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: Q: A: