The differences between IGMP versions are: (Multiple Choice)
- A . IGMPv1/v2 cannot elect the querier on its own, but IGMPv3 can.
- B . For members leaving, IGMPv2/v3 can leave actively, but IGMPv1 cannot.
- C . IGMPv1/v2/v3 cannot support the SSM model.
- D . IGMPv1 does not support specific group queries but IGMPv2 support.
Different port roles are defined in the RSTP protocol, the role of the port that cannot be in the forwarding state is: (Multiple Choice)
- A . Root Port
- B . Designated Port
- C . Backup Port
- D . Alternate Port
About the definition of router roles within or between OSPF areas, which is correct? (Multiple Choice)
- A . Internal router: refers to the router whose all interfaces belong to the same area.
- B . ABR: A router that connects one or more areas and connects to the backbone area. These routers act as routing gateways for inter-domain communication.
- C . Backbone router: refers to a router that has at least two interfaces that belong to the backbone area.
- D . ASBR: It can be an internal router, a backbone router, or a regional edge router.
In a network running STP, multiple topology change informations are sent when the network topology changes. How many kinds of topology change informations are defined in the RSTP network?
- A . One kind
- B . Two kinds
- C . Three kinds
- D . Four kinds
What are the major parts of the SNAP address used by the IS-IS protocol? (Multiple Choice)
- A . AREA ID
- B . DSCP
- C . SYSTEM ID
- D . SEL
The following is part of the router RTA configuration, for the configuration description of this part, the correct is: (Multiple Choice)
- A . A. Disable OSPF packet sending on interface gigabitethernet 1/0/0
- B . The interface cannot send HELLO messages
- C . The direct route of interface gigabitethernet 1/0/0 can still be advertised
- D . Cannot form a neighbor relationship with the directly connected neighbor on this interface.
In which of the following states do BGP peers refuse to initiate or accept connection requests?
- A . Established
- B . Idle
- C . Active
- D . OpenConfirm
Which statements about OSPF packets are true? (Select 2 answers)
- A . Hello packets can be sent immediately after the interface joined OSPF area.
- B . After received LS Update packets, the router must send LSAck for confirming.
- C . LS Update messages synchronize the link state database by sending detailed LSAs.
- D . LS Update packets are sent only after an adjacency is established.
In the RSTP protocol, the uplink port of the non-root switch has the parameter of the port identifier. The port identifier consists of two parts, they are:
- A . One-byte port priority and one-byte port number
- B . One-byte port priority and two-byte port number
- C . Two-byte port priority and one-byte port number
- D . Two-byte port priority and two-byte port number
Since the AS-PATH attribute cannot be function within the AS, it is specified that the BGP router will not advertise any updates from the IBGP peer to its IBGP peers.
- A . True
- B . False
In the static LACP mode, the correct description of the active link selection is: (Multiple Choice)
- A . After a member interface is added to the Eth-Trunk in static LACP mode, the member interface sends the information negotiation active port about the system priority, system MAC address, interface priority, and interface number to the peer.
- B . The higher the system LACP priority is, the higher the priority is. At both endsI of the devices, select the system with the larger LACP priority value as the active end. If the system LACP priority is the same, select the one with the higher MAC address as the active end.
- C . The passive end device determines the activity interface based on the active end interface LACP priority and interface ID (interface number).
- D . The interfaces selected by two-end device are inconsistent and the data can be forwarded normally.
Which of the following is the characteristics of the OSPF stub area?
- A . AS-external-LSAs can be published in the Stub area.
- B . The route to the outside of the AS can only be based on a default route generated manually by the ABR.
- C . Virtual connections cannot span the Stub area.
- D . Any area can be a stub area
The route injected into the BGP through the redistributed command has the Origin attribute of Incomplete.
- A . True
- B . False
Which of the following is incorrect about the OSPF protocol?
- A . When a router receives a Network-Summary-LSA, the router runs the SPF algorithm.
- B . Network-LSA is used to describe the link status information of the broadcast network segment and the NBMA network segment.
- C . Virtual connection is a virtual link that belongs to the backbone area (Area 0).
- D . Type-4 LSA is used to describe how to reach the ASBR and contain routing and topology information.
Autonomous System (AS) refers to a set of routers defined by users and using a unified routing policy.
- A . True
- B . False
As shown in the following figure, if you do not want employees of department A have mutual visits, employees in department B can communicate with each other, but different departments cannot communicate with each other, and all employees can access the company’s servers. To achieve this function through the MUX VLAN, the following statement is correct: 
- A . VLAN 2 is set to interworking VLAN
- B . VLAN 100 is a slave VLAN
- C . VLAN 3 is set to primary VLAN
- D . VLAN 3 is set to interworking VLAN
About multicast RPF check, which of the following statements is wrong? (Multiple Choice)
- A . Multicast RPF check is not rely on unicast routing.
- B . All multicast protocols use RPF check.
- C . The router receives the multicast packet but fails the RPF check and discards the received multicast packet.
- D . There are two RPF check functions. One is to prevent loops in multicast routes, the other is to prevent forwarding of redundant multicast data packets.
Regarding the description of IGMPv1 and IGMPv2, the correct one is: (Multiple Choice)
- A . IGMPv1 packet type does not include a leave member packets.
- B . IGMPv2 packet type includes member leave packets
- C . IGMPv1 supports universal group queries.
- D . IGMPv2 supports only general group queries.
How many types can the Hello packets of ISIS be divided into? (Multiple Choice)
- A . Level-1 LAN IIH
- B . Level-2 LAN IIH
- C . Level-3 LAN IIH
- D . P2P LAN IIH
When an operating OSPF router receives an LSA and the LSA does not exist in its link state database, how does the router handle this LSA?
- A . The router will silently discard this LSA without returning any messages.
- B . This LSA will be immediately flooded to other OSPF neighbors.
- C . The LSA is installed in its own link state database, and then this LSA is acknowledged by multicast.
- D . Check the age of the LSA to see if it expires.