H31-211 Online Practice Questions and Answers

In HDLC, the start and end fields of the flag frame are a fixed value, is it?

A. 11111111

B. 1111110

C. 0

D. 11111110

Which of the following statements about the exchange mode of the Ethernet switch are correct? (multiple choice)

A. Store and Forward mode does not detect framing errors

B. Cut-through mode, the switch starts to forward the frame after receiving the first 64 bytes of a frame.

C. Fragment-free mode detects errors in the first 64 bytes of the frame

D. Store and Forward mode discards frames with a total length of less than 64 bytes.

The .IP header contains an 8-bit Type of Service (TOS) field. Which of the following are the TOS fields? (Multiple choice)

A. 3bit COS field

B. 1bit minimum delay

C. 1bit maximum throughput

D. 2bit maximum reliability

Regarding the TTL field of the IP packet header, what are the following statements correct? (multiple choice)

A. The maximum possible value of TTL is 65535

B. Under normal circumstances, the router should not receive packets with TTL=0 from the interface.

C. TTL is mainly to prevent the cyclic forwarding of IP packets in the network, wasting network bandwidth.

D. Each time a IP packet passes through a network device, including Hub, LAN SWITCH, and router, the TTL value is subtracted from a certain value.

Which of the following options does the IP address use to distinguish between the network part and the host part?

A. Mask

B. Unicast

C. Broadcast

D. MAC address

Which of the following is the correct description of NAT? (multiple choice)

A. NAT is the abbreviation of Yingyin Address Translation

B. Address translation, also known as address translation, is used to convert between private and public network addresses.

C. When the host of the internal network accesses the external network, NAT is not required.

D. Address translation proposed to provide an effective way to solve the problem of IP address tension

In the frame relay network, what are the correct descriptions about the bandwidth control parameters?

(multiple choice)

A. CIR is the rate of user information transmission agreed by the network and the user, that is, the committed information rate.

B. Bc is the amount of data that the network allows users to transmit at CIR rate Tc intervals. They are related to Tc=Bc/CIR.

C. Be is the amount of data that the network allows users to transmit more than Bc during the Tc interval.

D. If the user transmits information at a rate less than or equal to CIR, the transmission of this part of information should be guaranteed.

Which of the following timers is used to prevent temporary loops when the Spanning Tree Protocol handles link failures?

A. Hello Time

B. Forward Delay

C. Max Age

D. Message Age

When the network topology changes, if the best path to the destination IP is no longer available, the dynamic routing protocol can adapt to the network change and determine the best path to the destination IP.

A. True

B. False

Which of the following is the transport layer protocol used by Telnet?

A. TCP

B. UDP

C. ECMP

D. UCMP