What are some common layer 2 encapsulations for a WAN link?（）

单项选择题Which WAN service utilizes two different encapsulation types (one for data and one for signaling) on its data link layer?（）

A. ISDN
B. Frame Relay
C. ATM
D. FDDI

单项选择题A router receives a packet on interface 172.16.45.66 26. The source IP of the packet is 172.16.45.127 26 and the destination is 172.16.46.191 26.How will the router handle the packet?（）

A. The destination is a host on another subnet, so the router will not forward the packet.
B. The destination is a host on the same subnet, so the router will forward the packet.
C. The destination is a broadcast address, so the router will not forward the packet.
D. The destination is a network address, so the router will forward the packet.

单项选择题Network equipment supporting the use of flow control mechanisms has been recently installed. What is the purpose of flow control in a data network?（）

A. It ensures that data is retransmitted if an acknowledgment is not received.
B. It reassembles segments in the correct order on the destination device.
C. It provides a mechanism for the receiver to control the transmission speed.
D. It regulates the size of each datagram segment.
E. All of the above are functions of flow control

单项选择题The command ip route 192.168.24.64 255.255.255.192 192.168.8.2 100 was configured on a router named TK1. No routing protocols or other static routes are configured on the Corporate router yet.Based on this information, which statement is true about this command?（）

A. This command sets a gateway of last resort for the TK1 router.
B. The number 100 indicates the number of hops to the destination network.
C. The interface with IP address 192.168.8.2 is on the TK1 router.
D. The command creates a static route for all IP traffic with the source address 192.168.24.64.
E. Packets destined for host 192.168.24.124 will be sent to 192.168.8.2.
F. None of the above

单项选择题A PC on a network segment sends data to another PC on a different segment.Which of the following correctly describe the correct order of how this data will be encapsulated?（）

A. Data, Frame, Packet, Segment, Bit
B. Data, Frame, Segment, Packet, Bit
C. Data, Packet, Frame, Segment, Bit
D. Data, Packet, Segment, Frame, Bit
E. Data, Segment, Frame, Packet, Bit
F. Data, Segment, Packet, Frame, Bit