Cisco 640-802 Online Practice Questions and Exam Preparation

Cisco 640-802 Online Questions & Answers

• Question 131:

  Which command enables IPv6 forwarding on a Cisco router?

  A. ipv6 local
  B. ipv6 host
  C. ipv6 unicast-routing
  D. ipv6 neighbor
  C. ipv6 unicast-routing

  ---

  To enable IPv6 routing on the Cisco router use the following command:

  ipv6 unicast-routing

  If this command is not recognized, your version of IOS does not support IPv6.

• Question 132:

  A national retail chain needs to design an IP addressing scheme to support a nationwide network. The company needs a minimum of 300 sub-networks and a maximum of 50 host addresses per subnet. Working with only one Class B address, which of the following subnet masks will support an appropriate addressing scheme? (Choose two.)

  A. 255.255.255.0
  B. 255.255.255.128
  C. 255.255.252.0
  D. 255.255.255.224
  E. 255.255.255.192
  F. 255.255.248.0
  B. 255.255.255.128
  E. 255.255.255.192

  ---

  Subnetting is used to break the network into smaller more efficient subnets to prevent excessive rates of Ethernet packet collision in a large network. Such subnets can be arranged hierarchically, with the organization's network address space (see also Autonomous System) partitioned into a tree-like structure. Routers are used to manage traffic and constitute borders between subnets. A routing prefix is the sequence of leading bits of an IP address that precede the portion of the address used as host identifier. In IPv4 networks, the routing prefix is often expressed as a "subnet mask", which is a bit mask covering the number of bits used in the prefix. An IPv4 subnet mask is frequently expressed in quad-dotted decimal representation, e.g., 255.255.255.0 is the subnet mask for the 192.168.1.0 network with a 24-bit routing prefix (192.168.1.0/24).

• Question 133:

  What are the Popular destinations for syslog messages to be saved? (Choose three)

  A. Flash
  B. The logging buffer .RAM
  C. The console terminal
  D. Other terminals
  E. Syslog server
  B. The logging buffer .RAM
  C. The console terminal
  E. Syslog server

  ---

  By default, switches send the output from system messages and debug privileged EXEC commands to a logging process. The logging process controls the distribution of logging messages to various destinations, such as the logging buffer (on RAM), terminal lines (console terminal), or a UNIX syslog server, depending on your configuration. The process also sends messages to the console.

  Note: Syslog messages can be written to a file in Flash memory although it is not a popular place to use. We can configure this feature with the command logging file flash:filename.

• Question 134:

  Which parameter or parameters are used to calculate OSPF cost in Cisco routers?

  A. Bandwidth
  B. Bandwidth and Delay
  C. Bandwidth, Delay, and MTU
  D. Bandwidth, MTU, Reliability, Delay, and Load
  A. Bandwidth

  ---

  The well-known formula to calculate OSPF cost is Cost = 108 / Bandwidth

• Question 135:

  Refer to the exhibit.

  

  A technician has installed SwitchB and needs to configure it for remote access from the management workstation connected to SwitchA. Which set of commands is required to accomplish this task?

  A. SwitchB(config)# interface FastEthernet 0/1 SwitchB(config-if)# ip address 192.168.8.252 255.255.255.0 SwitchB(config-if)# no shutdown
  B. SwitchB(config)# interface vlan 1 SwitchB(config-if)# ip address 192.168.8.252 255.255.255.0 SwitchB(config-if)# ip default-gateway 192.168.8.254 255.255.255.0 SwitchB(config-if)# no shutdown
  C. SwitchB(config)# ip default-gateway 192.168.8.254 SwitchB(config)# interface vlan 1 SwitchB(config-if)# ip address 192.168.8.252 255.255.255.0 SwitchB(config-if)# no shutdown
  D. SwitchB(config)# ip default-network 192.168.8.254 SwitchB(config)# interface vlan 1 SwitchB(config-if)# ip address 192.168.8.252 255.255.255.0 SwitchB(config-if)# no shutdown
  E. SwitchB(config)# ip route 192.168.8.254 255.255.255.0 SwitchB(config)# interface FastEthernet 0/1 SwitchB(config-if)# ip address 192.168.8.252 255.255.255.0 SwitchB(config-if)# no shutdown
  C. SwitchB(config)# ip default-gateway 192.168.8.254 SwitchB(config)# interface vlan 1 SwitchB(config-if)# ip address 192.168.8.252 255.255.255.0 SwitchB(config-if)# no shutdown

  ---

  To remote access to SwitchB, it must have a management IP address on a VLAN on that switch. Traditionally, we often use VLAN 1 as the management VLAN (but in fact it is not secure). In the exhibit, we can recognize that the Management Workstation is in a different subnet from the SwitchB. For intersubnetwork communication to occur, you must configure at least one default gateway. This default gateway is used to forward traffic originating from the switch only, not to forward traffic sent by devices connected to the switch.

• Question 136:

  At which layer of the OSI model is RSTP used to prevent loops?

  A. physical
  B. data link
  C. network
  D. transport
  B. data link

  ---

  RSTP and STP operate on switches and are based on the exchange of Bridge Protocol Data Units (BPDUs) between switches. One of the most important fields in BPDUs is the Bridge Priority in which the MAC address is used to elect the Root Bridge -> RSTP operates at Layer 2 ?Data Link layer >;.

• Question 137:

  What are three values that must be the same within a sequence of packets for Netflow to consider them a network flow? (Choose three.)

  A. source IP address
  B. source MAC address
  C. egress interface
  D. ingress interface
  E. destination IP address
  F. IP next-hop
  A. source IP address
  D. ingress interface
  E. destination IP address

  ---

  Each packet that is forwarded within a router or switch is examined for a set of IP packet attributes. These attributes are the IP packet identity or fingerprint of the packet and determine if the packet is unique or similar to other packets. Traditionally, an IP Flow is based on a set of 5 and up to 7 IP packet attributes. IP Packet attributes used by NetFlow: ?IP source address ?IP destination address ?Source port ?Destination port ?Layer 3 protocol type ?Class of Service ?Router or switch interface All packets with the same source/destination IP address, source/destination ports, protocol interface and class of service are grouped into a flow and then packets and bytes are tallied. This methodology of fingerprinting or determining a flow is scalable because a large amount of network information is condensed into a database of NetFlow information called the NetFlow cache.

  Reference: http://www.cisco.com/c/en/us/products/collateral/ios-nx-os-software/ios-netflow/prod_white_paper0900aecd80406232.html

• Question 138:

  What is the difference between a CSU/DSU and a modem?

  A. A CSU/DSU converts analog signals from a router to a leased line; a modem converts analog signals from a router to a leased line.
  B. A CSU/DSU converts analog signals from a router to a phone line; a modem converts digital signals from a router to a leased line.
  C. A CSU/DSU converts digital signals from a router to a phone line; a modem converts analog signals from a router to a phone line.
  D. A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line.
  D. A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line.

  ---

  CSU/DSU is used to convert digital signals from a router to a network circuit such as a T1, while a modem is used to convert digital signals over a regular POTS line.

• Question 139:

  Refer to the exhibit.

  

  A network administrator is configuring an EtherChannel between SW1 and SW2. The SW1 configuration is shown. What is the correct configuration for SW2?

  A. interface FastEthernet 0/1 channel-group 1 mode active switchport trunk encapsulation dot1q switchport mode trunk interface FastEthernet 0/2 channel-group 1 mode active switchport trunk encapsulation dot1q switchport mode trunk
  B. interface FastEthernet 0/1 channel-group 2 mode auto switchport trunk encapsulation dot1q switchport mode trunk interface FastEthernet 0/2 channel-group 2 mode auto switchport trunk encapsulation dot1q switchport mode trunk
  C. interface FastEthernet 0/1 channel-group 1 mode desirable switchport trunk encapsulation dot1q switchport mode trunk interface FastEthernet 0/2 channel-group 1 mode desirable switchport trunk encapsulation dot1q switchport mode trunk
  D. interface FastEthernet 0/1 channel-group 1 mode passive switchport trunk encapsulation dot1q switchport mode trunk interface FastEthernet 0/2 channel-group 1 mode passive switchport trunk encapsulation dot1q switchport mode trunk
  C. interface FastEthernet 0/1 channel-group 1 mode desirable switchport trunk encapsulation dot1q switchport mode trunk interface FastEthernet 0/2 channel-group 1 mode desirable switchport trunk encapsulation dot1q switchport mode trunk

  ---

  If the etherchannel was configured with mode "auto", it was using PagP, so, we need to configure the other switch with "desirable" mode.

  PagP modes: auto | Desirable LACP modes: active | pasive

• Question 140:

  A network administrator needs to configure port security on a switch. Which two statements are true? (Choose two.)

  A. The network administrator can apply port security to dynamic access ports.
  B. The network administrator can apply port security to EtherChannels.
  C. When dynamic MAC address learning is enabled on an interface, the switch can learn new addresses, up to the maximum defined.
  D. The sticky learning feature allows the addition of dynamically learned addresses to the running configuration.
  E. The network administrator can configure static secure or sticky secure MAC addresses in the voice VLAN.
  C. When dynamic MAC address learning is enabled on an interface, the switch can learn new addresses, up to the maximum defined.
  D. The sticky learning feature allows the addition of dynamically learned addresses to the running configuration.

  ---

  Follow these guidelines when configuring port security:

  +

  Port security can only be configured on static access ports, trunk ports, or 802.1Q tunnel ports.

  +

  A secure port cannot be a dynamic access port.

  +

  A secure port cannot be a destination port for Switched Port Analyzer (SPAN).

  +

  A secure port cannot belong to a Fast EtherChannel or Gigabit EtherChannel port group.

  +

  You cannot configure static secure or sticky secure MAC addresses on a voice VLAN.

  +

  When you enable port security on an interface that is also configured with a voice VLAN, you must set the maximum allowed secure addresses on the port to at least two.

  +

  If any type of port security is enabled on the access VLAN, dynamic port security is automatically enabled on the voice VLAN.

  +

  When a voice VLAN is configured on a secure port that is also configured as a sticky secure port, all addresses seen on the voice VLAN are learned as dynamic secure addresses, and all addresses seen on the access VLAN (to which the port belongs) are learned as sticky secure addresses.

  +

  The switch does not support port security aging of sticky secure MAC addresses.

  +

  The protect and restrict options cannot be simultaneously enabled on an interface.

  (Reference: http://www.cisco.com/en/US/docs/switches/lan/catalyst3550/software/release/12.1_19_ea1/configuration/guide/swtrafc.html)