Tranport layer is to provide efficient, reliable, and cost-effective service to its users.
查看答案
Putting Transport layer on top of the network layer, can make the users have some control over the quality of the service.
What will a Layer 2 switch do if it receives a frame with a destination MAC address that is not found in its MAC address table?
A. he frame is dropped.
B. The frame is addressed with a broadcast MAC address and sent out all ports
C. The frame is sent out all ports except the receiving port.
D. An ARP request is sent out all ports except the receiving port.
For Ethernet:
A. The Ethernet frame format is defined by IP protocol
B. 10Base2-T indicates the cable is twisted pair
C. In Ethernet frame header, the source address is a 8 bytes field.
D. Ethernet frame format is the same as IEEE802.3 format.
For MAC sublayer protocols, which one is CORRECT
A. For CSMA, a frame is sent at once when it is generated
B. For pure ALOHA, collision will never occur
C. For pure ALOHA, frame is sent only at the very beginning of interval
D. 1-persistent CSMA is a special example of p-persistent CSMA
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