1. Which of the following options can improve the service experience of multicast users when switching channels (shorter switching time)?

2. Enable IGMP-snooping on the layer 2. When the switch port receives an IGMP join message, it monitors the message and adds the corresponding port to the multicast group.

3. The IGMP version on the OLT is configured as V2. What kind of processing will the OLT do after receiving the igmr v3 join message forwarded from OnT?

4. When configuring the multicast service on the MA5600T/MA5680T, the multicast vlan program adopts the static configuration method. Which of the following options must be configured, otherwise the multicast program may not be watched?

5. The range of class D multicast addresses is from 224.0.0.0 to 238.255.255.255.

6. A total of 100 multicast users on the OLT are watching 20 multicast programs. If each multicast program occupies a bandwidth of 2M, how much multicast traffic does the OLT uplink port currently have?

7. Multicast technology effectively solves the problem of single-point sending and multi-point receiving, and realizes efficient point-to-multipoint data transmission in the IP network.

8. The correct multicast MAC address corresponding to the multicast IP address 227.120.1.32 is:

9. Regarding multicast, which of the following descriptions is incorrect?

10. The Max-Forwards field can be used in the S1P message to solve the loop QUESTION NO: to avoid endless message forwarding.

11. When the invitation message sent by user A reaches user B after passing through servers C, D, and E, the server address recorded in the VIA field in the message received by user B from top to bottom is:

12. The SIP user and the server are completed the establishment, maintenance, and removal of a voice path through a series of message interactions. Therefore, each information contained in the SIP text is one-to-one, and there will be no single information values appears multiple times.

13. The complete SIP message interaction process will include multiple request and response messages. A field can be used in the header field of the SIP message to describe the specific request corresponding to the current response message. This field is:

14. The maximum splitting ratio supported by 10GGPON is:

15. During the evolution of EPON to 10G EPON, WDM wavelength division modules are added at the central office to achieve a smooth transition, and ODN coexists.

16. Under the H.248 protocol, if the signaling IP and media IP are both 10.1.1.100/8, and the voice gateway is 10.1.1.1, when configuring the voIP service, which of the following command is wrong?

17. The total downlink bandwidth of the 10G EPON PONI port is the sum of the EPON downlink bandwidth and the 10GEPON downlink bandwidth.

18. Under IGMP snooping, two users under the OLT order the same program, and olt sends two join messages to the multicast router.

19. When the backbone fiber is broken or the OLT cannot detect the expected optical signal (LOS) alarm, the possible cause is: (Multiple Choice)

20. What is the downlink wavelength in the 10GGPON system?