100-105 Exam - ICND1 Cisco Interconnecting Cisco Networking Devices Part 1 (ICND1 v3.0)

Answer: D

Explanation:

Static routing can be used to define an exit point from a router when no other routes are available or necessary. This is called a default route.

Answer: C

Answer: A

Answer: B

Explanation:

DHCPv6 Technology Overview

IPv6 Internet Address Assignment Overview

IPv6 has been developed with Internet Address assignment dynamics in mind. Being aware that IPv6 Internet addresses are 128 bits in length and written in hexadecimals makes automation of address-assignment an important aspect within network design.

These attributes make it inconvenient for a user to manually assign IPv6 addresses, as the format is not naturally intuitive to the human eye. To facilitate address assignment with little or no human intervention, several methods and technologies have been developed to automate the process of address and configuration parameter assignment to IPv6 hosts. The various IPv6 address assignment methods are as follows:

1. Manual Assignment

An IPv6 address can be statically configured by a human operator. However, manual assignment is quite open to errors and operational overhead due to the 128 bit length and hexadecimal attributes of the addresses, although for router interfaces and static network elements and resources this can be an appropriate solution.

2. Stateless Address Autoconfiguration (RFC2462)

Stateless Address Autoconfiguration (SLAAC) is one of the most convenient methods to assign Internet addresses to IPv6 nodes. This method does not require any human intervention at all from an IPv6 user. If one wants to use IPv6 SLAAC on an IPv6 node, it is important that this IPv6 node is connected to a network with at least one IPv6 router connected. This router is configured by the network administrator and sends out Router Advertisement announcements onto the link. These announcements can allow the on-link connected IPv6 nodes to configure themselves with IPv6 address and routing parameters, as specified in RFC2462, without further human intervention.

3. Stateful DHCPv6

The Dynamic Host Configuration Protocol for IPv6 (DHCPv6) has been standardized by the IETF through RFC3315. DHCPv6 enables DHCP servers to pass configuration parameters, such as IPv6 network addresses, to IPv6 nodes. It offers the capability of automatic allocation of reusable network addresses and additional configuration flexibility. This protocol is a stateful counterpart to "IPv6 Stateless Address Autoconfiguration" (RFC 2462), and can be used separately, or in addition to the stateless autoconfiguration to obtain configuration parameters.

4. DHCPv6-PD

DHCPv6 Prefix Delegation (DHCPv6-PD) is an extension to DHCPv6, and is specified in RFC3633. Classical DHCPv6 is typically focused upon parameter assignment from a DHCPv6 server to an IPv6 host running a DHCPv6 protocol stack. A practical example would be the stateful address assignment of "2001:db8::1" from a DHCPv6 server to a DHCPv6 client. DHCPv6-PD however is aimed at assigning complete subnets and other network and interface parameters from a DHCPv6-PD server to a DHCPv6-PD client. This means that instead of a single address assignment, DHCPv6-PD will assign a set of IPv6 "subnets". An example could be the assignment of "2001:db8::/60" from a DHCPv6-PD server to a DHCPv6-PD client. This will allow the DHCPv6-PD client (often a CPE device) to segment the received address IPv6 address space, and assign it dynamically to its IPv6 enabled interfaces.

5. Stateless DHCPv6

Stateless DHCPv6 is a combination of "stateless Address Autoconfiguration" and "Dynamic Host Configuration Protocol for IPv6" and is specified by RFC3736. When using stateless- DHCPv6, a device will use Stateless Address Auto-Configuration (SLAAC) to assign one or more IPv6 addresses to an interface, while it utilizes DHCPv6 to receive "additional parameters" which may not be available through SLAAC. For example, additional parameters could include information such as DNS or NTP server addresses, and are provided in a stateless manner by DHCPv6. Using stateless DHCPv6 means that the DHCPv6 server does not need to keep track of any state of assigned IPv6 addresses, and there is no need for state refreshment as result. On network media supporting a large number of hosts associated to a single DHCPv6 server, this could mean a significant reduction in DHCPv6 messages due to the reduced need for address state refreshments. From Cisco IOS 12.4(15)T onwards the client can also receive timing information, in addition to the "additional parameters" through DHCPv6. This timing information provides an indication to a host when it should refresh its DHCPv6 configuration data. This behavior (RFC4242) is particularly useful in unstable environments where changes are likely to occur.

Answer: D

Answer: B

Answer:

Specify appropriate devices and drag them on the "Device" boxes

For the device at the bottom-right box, we notice that it has 2 interfaces Fa0/2 and Fa0/4; moreover the link connects the PC on the right with the device on the bottom-right is a straight-through link -> it is a switch

The question stated that this topology contains 3 routers and 1 switch -> two other devices are routers

Place them on appropriate locations as following:

(Host D and host E will be automatically added after placing two routers. Click on them to access neighboring routers)

Specify appropriate connections between these devices:

+ The router on the left is connected with the Main router through FastEthernet interfaces: use a crossover cable

+ The router on the right is connected with the Main router through Serial interfaces: use a serial cable

+ The router on the right and the Switch: use a straight-through cable

+ The router on the left and the computer: use a crossover cable

(To remember which type of cable you should use, follow these tips:

- To connect two serial interfaces of 2 routers we use serial cable

- To specify when we use crossover cable or straight-through cable, we should remember:

Group 1: Router, Host, Server

Group 2: Hub, Switch

One device in group 1 + One device in group 2: use straight-through cable

Two devices in the same group: use crossover cable

For example, we use straight-through cable to connect switch to router, switch to host, hub to host, hub to server... and we use crossover cable to connect switch to switch, switch to hub, router to router, host to host.)

Assign appropriate IP addresses for interfaces:

From Main router, use show running-config command.

(Notice that you may see different IP addresses in the real CCNA exam, the ones shown above are just used for demonstration)

From the output we learned that the ip address of Fa0/0 interface of the Main router is 192.168.152.177/28. This address belongs to a subnetwork which has:

Increment: 16 (/28 = 255.255.255.240 or 1111 1111.1111 1111.1111 1111.1111 0000)

Network address: 192.168.152.176 (because 176 = 16 * 11 and 176 < 177)

Broadcast address: 192.168.152.191 (because 191 = 176 + 16 - 1)

And we can pick up an ip address from the list that belongs to this subnetwork:

192.168.152.190 and assign it to the Fa0/0 interface the router on the left

Use the same method for interface Serial0/0 with an ip address of 192.168.152.161 Increment: 16

Network address: 192.168.152.160 (because 160 = 16 * 10 and 160 < 161)

Broadcast address: 192.168.152.175 (because 176 = 160 + 16 - 1)

-> and we choose 192.168.152.174 for Serial0/0 interface of the router on the right Interface Fa0/1 of the router on the left

IP (of the computer on the left) : 192.168.152.129/28 Increment: 16

Network address: 192.168.152.128 (because 128 = 16 * 8 and 128 < 129)

Broadcast address: 192.168.152.143 (because 143 = 128 + 16 - 1)

-> we choose 192.168.152.142 from the list Interface Fa0/0 of the router on the right

IP (of the computer on the left) : 192.168.152.225/28 Increment: 16

Network address: 192.168.152.224 (because 224 = 16 * 14 and 224 < 225)

Broadcast address: 192.168.152.239 (because 239 = 224 + 16 - 1)

-> we choose 192.168.152.238 from the list

Let's have a look at the picture below to summarize

Configure two routers on the left and right with these commands: Router1 = router on the left

Assign appropriate IP addresses to Fa0/0 & Fa0/1 interfaces: Router1>enable

Router1#configure terminal Router1(config)#interface fa0/0

Router1(config-if)#ip address 192.168.152.190 255.255.255.240 Router1(config-if)#no shutdown

Router1(config-if)#interface fa0/1

Router1(config-if)#ip address 192.168.152.142 255.255.255.240 Router1(config-if)#no shutdown

Set passwords (configure on two routers)

+ Console password: Router1(config-if)#exit Router1(config)#line console 0

Router1(config-line)#password consolepw Router1(config-line)#login

Router1(config-line)#exit

+ Telnet password: Router1(config)#line vty 0 4 Router1(config-line)#password telnetpw Router1(config-line)#login Router1(config-line)#exit

+ Privilege mode password: Router1(config)#enable password privpw Save the configuration: Router1(config)#exit

Router1#copy running-config startup-config

Configure IP addresses of Router2 (router on the right) Router2>enable

Router2#configure terminal Router2(config)#interface fa0/0

Router2(config-if)#ip address 192.168.152.238 255.255.255.240 Router2(config-if)#no shutdown

Router2(config-if)#interface serial0/0

Router2(config-if)#ip address 192.168.152.174 255.255.255.240 Router2(config-if)#no shutdown

Then set the console, telnet and privilege mode passwords for Router2 as we did for Router1, remember to save the configuration when you finished.

Topic 7, Mix Questions

204.Which statement about 6to4 tunneling is true?

A. One tunnel endpoint must be configured with IPv4 only

B. It establishes a point-to-point tunnel

C. Both tunnel endpoints must be configured with IPv4 only

D. Both tunnel endpoints must support IPv4 and IPv6

Answer:

ROUTER-M> enable PassworD. Cisco

ROUTER-M# config t

ROUTER-M(config)# interface e0

ROUTER-M(config-if)# ip address 192.168.160.14 255.255.255.240

ROUTER-M(config-if)# no shutdown

ROUTER -M(config-if)# exit

ROUTER -M(config)# interface s0

ROUTER-M(config-if)# ip address 192.168.160.30 255.255.255.240

ROUTER-M(config-if)# no shutdown

ROUTER-M(config-if)# end

ROUTER-M# copy run start

Answer: C

Explanation: Explanation

The Administrative Distances (AD) of popular routing protocols are listed below:

After the show ip route command has been entered, the following routes are displayed. Which route will not be entered into the routing table of a neighboring router?

A. R 192.168.8.0/24 [120/1] via 192.168.2.2, 00:00:10, Serial0

B. R 192.168.11.0/24 [120/7] via 192.168.9.1, 00:00:03, Serial1

C. C 192.168.1.0/24 is directly connected, Ethernet0

D. R 192.168.5.0/24 [120/15] via 192.168.2.2, 00:00:10, Serial0

Answer: D