Juniper Updated JN0-351 Exam Questions and Answers by denver

A route reflector is a BGP router that is allowed to break the iBGP loop avoidance rule and advertise routes received from an iBGP peer to another iBGP peer under specific conditions 1 .  A route reflector can have three types of peerings: EBGP neighbor, IBGP client neighbor, and IBGP non-client neighbor 2 .  A cluster is a group of route reflectors and their clients that are fully meshed 3 .  The cluster ID is a 4-byte value that identifies the route reflector cluster and is carried in the ORIGINATOR_ID attribute of the BGP update message 4 . The cluster ID is used to prevent routing loops among route reflectors and their clients.  If a route reflector receives a route with its own cluster ID, it discards the route 5 . Therefore, the cluster ID is required to prevent routing loops when using route reflectors.

According to the Juniper documentation 1 , the output of the show vlans command displays the forwarding options for the VLAN, including the DHCP security features. In the exhibit, the output shows that DHCP security is enabled, and that ARP inspection and IP source guard are also enabled. These features work together to protect the switch from IP spoofing and ARP spoofing attacks. DHCP snooping builds a database of IP/MAC bindings by snooping DHCP messages. ARP inspection validates ARP packets against the DHCP snooping database and drops invalid packets.  IP source guard checks the IP and MAC source addresses of packets against the DHCP snooping database and drops spoofed packets 2 3 . Therefore, the correct answer is A, B, and C.

The other options are not correct because:

D. The DHCP snooping database is not protected by default.  To protect the database from corruption or loss, you need to configure a file name and a location for storing the database, and enable periodic write operations to the file 4 . The exhibit does not show any such configuration.

E. DHCP snooping is not enabled for IPv6 traffic by default.  To enable DHCPv6 snooping, you need to configure a DHCPv6 relay agent and specify the trusted interfaces for DHCPv6 messages 5 . The exhibit does not show any such configuration.