Q161. - (Topic 7)
Refer to the topology. Your company has decided to connect the main office with three
other remote branch offices using point-to-point serial links.
You are required to troubleshoot and resolve OSPF neighbor adjacency issues between the main office and the routers located in the remote branch offices.
An OSPF neighbor adjacency is not formed between R3 in the main office and R4 in the Branch1 office. What is causing the problem?
A. There is an area ID mismatch.
B. There is a Layer 2 issue; an encapsulation mismatch on serial links.
C. There is an OSPF hello and dead interval mismatch.
D. The R3 router ID is configured on R4.
A show running-config command on R3 and R4 shows that R4 is incorrectly configured for area 2:
Q162. - (Topic 4)
Which two statements about using the CHAP authentication mechanism in a PPP link are true? (Choose two.)
A. CHAP uses a two-way handshake.
B. CHAP uses a three-way handshake.
C. CHAP authentication periodically occurs after link establishment.
D. CHAP authentication passwords are sent in plaintext.
E. CHAP authentication is performed only upon link establishment.
F. CHAP has no protection from playback attacks.
CHAP is an authentication scheme used by Point to Point Protocol (PPP) servers to validate the identity of remote clients. CHAP periodically verifies the identity of the client by using a three-way handshake. This happens at the time of establishing the initial link (LCP), and may happen again at any time afterwards. The verification is based on a shared secret (such as the client user's password).
Q163. - (Topic 8)
when you troubleshoot an IPv4 connectivity issue on a router, which three router configuration checks you must perform?
A. Verify that the router interface IP address IP address is correct.
B. Verify that the DNS is configured correctly.
C. Verify that the router and the host use the same subnet mask.
D. Verify that the router firmware is up-to-date.
E. Verify that a default route is configured.
F. Verify that the route appears in the routing table
Q164. - (Topic 8)
Which MAC protocol sets a random timer to reattempt communication?
A. IEEE 802.1x
Q165. - (Topic 4)
Which two options are valid WAN connectivity methods? (Choose two.)
The Point-to-Point Protocol (PPP) provides a standard method for transporting multi- protocol datagrams over point-to-point links. PPP was originally emerged as an encapsulation protocol for transporting IP traffic between two peers. It is a data link layer protocol used for WAN connections.
DSL is also considered a WAN connection, as it can be used to connect networks, typically when used with VPN technology.
Q166. - (Topic 3)
What are two enhancements that OSPFv3 supports over OSPFv2? (Choose two.)
A. It requires the use of ARP.
B. It can support multiple IPv6 subnets on a single link.
C. It supports up to 2 instances of OSPFv3 over a common link.
D. It routes over links rather than over networks.
Here is a list of the differences between OSPFv2 and OSPFv3:
✑ They use different address families (OSPFv2 is for IPv4-only, OSPFv3 can be used for IPv6-only or both protocols
✑ OSPFv3 introduces new LSA types
✑ OSPFv3 has different packet format
✑ OSPFv3 uses different flooding scope bits (U/S2/S1)
✑ OSPFv3 adjacencies are formed over link-local IPv6 communications
✑ OSPFv3 runs per-link rather than per-subnet
✑ OSPFv3 supports multiple instances on a single link, Interfaces can have multiple IPv6 addresses
✑ OSPFv3 uses multicast addresses FF02::5 (all OSPF routers), FF02::6 (all OSPF DRs)
✑ OSPFv3 Neighbor Authentication done with IPsec (AH)
✑ OSPFv2 Router ID (RID) must be manually configured, still a 32-bit number
Reference: http://www.networkworld.com/article/2225270/cisco-subnet/ospfv3-for-ipv4-and- ipv6.html
Q167. - (Topic 8)
Which option describes how a switch in rapid PVST+ mode responds to a topology change?
A. It immediately deletes dynamic MAC addresses that were learned by all ports on the switch.
B. It sets a timer to delete all MAC addresses that were learned dynamically by ports in the same STP instance.
C. It sets a timer to delete dynamic MAC addresses that were learned by all ports on the switch.
D. It immediately deletes all MAC addresses that were learned dynamically by ports in the same STP instance.
Rapid PVST+This spanning-tree mode is the same as PVST+ except that is uses a rapid convergence based on the IEEE 802.1w standard. To provide rapid convergence, the rapid PVST+ immediately deletes dynamically learned MAC address entries on a per-port basis upon receiving a topology change. By contrast, PVST+ uses a short aging time for dynamically learned MAC address entries.
The rapid PVST+ uses the same configuration as PVST+ (except where noted), and the switch needs only minimal extra configuration. The benefit of rapid PVST+ is that you can migrate a large PVST+ install base to rapid PVST+ without having to learn the complexities of the MSTP configuration and without having to reprovision your network. In rapid-PVST+ mode, each VLAN runs its own spanning-tree instance up to the maximum supported.
Q168. - (Topic 8)
Which command can you execute to set the user inactivity timer to 10 seconds?
A. SW1(config-line)#exec-timeout 0 10
B. SW1(config-line)#exec-timeout 10
C. SW1(config-line)#absolute-timeout 0 10
D. SW1(config-line)#absolute-timeout 10
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