The two routers MSR-1 and MSR-2 are interconnected through the S0/0 interface, and the two routers learn the routes of the LAN segment by running the RIP protocol.
See the following configuration commands on MSR-1:
[MSR-1-Serial0/0] rip authentication-mode md5 rfc2453 H3C
Then the correct interpretation of this command is ______. (Multiple choice)

A network connection is as follows:
HostA----GE0/0--MSR-1--S1/0---------S1/0--MSR-2--GE0/0----HostB
The customer requires that only ICMP messages between HostA and HostB are restricted. Which of the following is feasible? (multiple choice)

The two WAN interfaces S1/0 and S1/1 of the router MSR-1 are connected to the routers MSR-2 and MSR-3 respectively.
At the same time, the Ethernet port of MSR-1 is connected to MSR-4. All four routers have run the RIP protocol and completed routing learning correctly. All routers have started all the features of RIP to prevent loops. At this time, it is found that the MSR -2 The network 192.168.0.0 fails, then ______ after a certain period of time. (Multiple choice)

A network connection is like:
HostA----GE0/0--MSR-1--S1/0------S1/0--MSR-2--GE0/0----HostB
Among them, the two empty-configured MSR routers MSR-1 and MSR-2 are interconnected back-to-back through their S1/0 interfaces, and their GE0/0 interfaces are respectively connected to the client hosts HostA and HostB. All physical connections are normal.
Now add the following configuration under the S1/0 interface of MSR-2:
interface Serial1/0
link-protocol ppp
ppp pap local-user 123 password simple 456
ip address 6.6.6.1 255.255.255.0
So ______ . (Multiple choice)

The following statement about STP is correct. ______. (Multiple choice)