Cisco 640-802 Online Practice Questions and Exam Preparation

Cisco 640-802 Online Questions & Answers

• Question 91:

  If primary and secondary root switches with priority 16384 both experience catastrophic losses, which tertiary switch can take over?

  A. a switch with priority 20480
  B. a switch with priority 8192
  C. a switch with priority 4096
  D. a switch with priority 12288
  A. a switch with priority 20480

• Question 92:

  Refer to the exhibit.

  

  Based on the information given, which switch will be elected root bridge and why?

  A. Switch A, because it has the lowest MAC address
  B. Switch A, because it is the most centrally located switch
  C. Switch B, because it has the highest MAC address
  D. Switch C, because it is the most centrally located switch
  E. Switch C, because it has the lowest priority
  F. Switch D, because it has the highest priority
  E. Switch C, because it has the lowest priority

  ---

  To elect the root bridge in the LAN, first check the priority value. The switch having the lowest priority will win the election process. If Priority Value is the same then it checks the MAC Address; the switch having the lowest MAC Address will become the root bridge. In this case, switch C has the lowest MAC Address so it becomes the root bridge.

• Question 93:

  Cisco Catalyst switches CAT1 and CAT2 have a connection between them using ports FA0/13. An 802.1Q trunk is configured between the two switches. On CAT1, VLAN 10 is chosen as native, but on CAT2 the native VLAN is not specified. What will happen in this scenario?

  A. 802.1Q giants frames could saturate the link.
  B. VLAN 10 on CAT1 and VLAN 1 on CAT2 will send untagged frames.
  C. A native VLAN mismatch error message will appear.
  D. VLAN 10 on CAT1 and VLAN 1 on CAT2 will send tagged frames.
  C. A native VLAN mismatch error message will appear.

  ---

  A "native VLAN mismatch" error will appear by CDP if there is a native VLAN mismatch on an 802.1Q link. "VLAN mismatch" can cause traffic from one vlan to leak into another vlan.

• Question 94:

  Refer to the exhibit.

  

  An attempt to deny web access to a subnet blocks all traffic from the subnet. Which interface command immediately removes the effect of ACL 102?

  A. no ip access-class 102 in
  B. no ip access-class 102 out
  C. no ip access-group 102 in
  D. no ip access-group 102 out
  E. no ip access-list 102 in
  D. no ip access-group 102 out

  ---

  The "ip access-group" is used to apply and ACL to an interface. From the output shown, we know that the ACL is applied to outbound traffic, so "no ip access-group 102 out" will remove the effect of this ACL.

• Question 95:

  When you are troubleshooting an ACL issue on a router, which command would you use to verify which interfaces are affected by the ACL?

  A. show ip access-lists
  B. show access-lists
  C. show interface
  D. show ip interface
  E. list ip interface
  D. show ip interface

  ---

  Incorrect answer:

  show ip access-lists does not show interfaces affected by an ACL.

• Question 96:

  In an Ethernet network, under what two scenarios can devices transmit? (Choose two.)

  A. when they receive a special token
  B. when there is a carrier
  C. when they detect no other devices are sending
  D. when the medium is idle E. when the server grants access
  C. when they detect no other devices are sending
  D. when the medium is idle E. when the server grants access

  ---

  Ethernet network is a shared environment so all devices have the right to access to the medium. If more than one device transmits simultaneously, the signals collide and cannot reach the destination.

  If a device detects another device is sending, it will wait for a specified amount of time before attempting to transmit.

  When there is no traffic detected, a device will transmit its message. While this transmission is occurring, the device continues to listen for traffic or collisions on the LAN. After the message is sent, the device returns to its default listening

  mode.

• Question 97:

  Users have been complaining that their Frame Relay connection to the corporate site is very slow. The network administrator suspects that the link is overloaded.

  

  Based on the partial output of the Router# show frame relay pvc command shown in the graphic, which output value indicates to the local router that traffic sent to the corporate site is experiencing congestion?

  A. DLCI = 100
  B. last time PVC status changed 00:25:40
  C. in BECN packets 192
  D. in FECN packets 147
  E. in DE packets 0
  C. in BECN packets 192

  ---

  If device A is sending data to device B across a Frame Relay infrastructure and one of the intermediate Frame Relay switches encounters congestion, congestion being full buffers, over-subscribed port, overloaded resources, etc, it will set the BECN bit on packets being returned to the sending device and the FECN bit on the packets being sent to the receiving device.

• Question 98:

  Which three statements about link-state routing are true? (Choose three.)

  A. Routes are updated when a change in topology occurs.
  B. Updates are sent to a multicast address by default.
  C. OSPF is a link-state protocol.
  D. Updates are sent to a broadcast address.
  E. RIP is a link-state protocol.
  F. It uses split horizon.
  A. Routes are updated when a change in topology occurs.
  B. Updates are sent to a multicast address by default.
  C. OSPF is a link-state protocol.

• Question 99:

  A network interface port has collision detection and carrier sensing enabled on a shared twisted pair network. From this statement, what is known about the network interface port?

  A. This is a 10 Mb/s switch port.
  B. This is a 100 Mb/s switch port.
  C. This is an Ethernet port operating at half duplex.
  D. This is an Ethernet port operating at full duplex.
  E. This is a port on a network interface card in a PC.
  C. This is an Ethernet port operating at half duplex.

  ---

  Modern Ethernet networks built with switches and full-duplex connections no longer utilize CSMA/CD. CSMA/CD is only used in obsolete shared media Ethernet (which uses repeater or hub).

• Question 100:

  Which two states are the port states when RSTP has converged? (Choose two.)

  A. discarding
  B. listening
  C. learning
  D. forwarding
  E. disabled
  A. discarding
  D. forwarding

  ---

  There are only three port states left in RSTP that correspond to the three possible operational states. The 802.1D disabled, blocking, and listening states are merged into a unique 802.1w discarding state.

  

  Reference: http://www.cisco.com/en/US/tech/tk389/tk621/technologies_white_paper09186a0080094cfa.shtml#states