CCNA 1 v7 Modules 11 – 13: IP Addressing - Test Online

Hint

The binary format for 255.255.255.224 is 11111111.11111111.11111111.11100000. The prefix length is the number of consecutive 1s in the subnet mask. Therefore, the prefix length is /27.

Hint

Each network that is directly connected to an interface on a router requires its own subnet. The formula 2n, where n is the number of bits borrowed, is used to calculate the available number of subnets when borrowing a specific number of bits.

Hint

A /26 prefix gives 6 host bits, which provides a total of 64 addresses, because 26 = 64. Subtracting the network and broadcast addresses leaves 62 usable host addresses.

Hint

A mask of 255.255.252.0 is equal to a prefix of /22. A /22 prefix provides 22 bits for the network portion and leaves 10 bits for the host portion. The 10 bits in the host portion will provide 1022 usable IP addresses (210 – 2 = 1022).

Hint

RFC 1918, Address Allocation for Private Internets, defines three blocks of IPv4 address for private networks that should not be routable on the public Internet.

• 10.0.0.0/8
• 172.16.0.0/12
• 192.168.0.0/16

Hint

The 172.16.16.0/22 network has 22 bits in the network portion and 10 bits in the host portion. Converting the network address to binary yields a subnet mask of 255.255.252.0. The range of addresses in this network will end with the last address available before 172.16.20.0. Valid host addresses for this network range from 172.16.16.1-172.16.19.254, making 172.16.19.255 the broadcast address.

Hint

The subnet mask of 255.255.255.0 has 8 host bits. The mask of 255.255.255.128 results in 7 host bits. The mask of 255.255.255.224 has 5 host bits. Finally, 255.255.255.240 represents 4 host bits.

Hint

Addresses 10.16.10.0 through 10.16.10.63 are taken for the leftmost network. Addresses 10.16.10.192 through 10.16.10.207 are used by the center network.The address space from 208-255 assumes a /28 mask, which does not allow enough host bits to accommodate 25 host addresses.The address ranges that are available include 10.16.10.64/26 and10.16.10.128/26. To accommodate 25 hosts, 5 host bits are needed, so a /27 mask is necessary. Four possible /27 subnets could be created from the available addresses between 10.16.10.64 and 10.16.10.191: 10.16.10.64/27 10.16.10.96/27 10.16.10.128/27 10.16.10.160/27

Hint

A /26 mask is the same as 255.255.255.192. The mask leaves 6 host bits. With 6 host bits, 64 IP addresses are possible. One address represents the subnet number and one address represents the broadcast address, which means that 62 addresses can then be used to assign to network devices.

Hint

Network A needs to use 192.168.0.128 /25, which yields 128 host addresses. Network B needs to use 192.168.0.0 /26, which yields 64 host addresses. Network C needs to use 192.168.0.96 /27, which yields 32 host addresses. Network D needs to use 192.168.0.80/30, which yields 4 host addresses.

Hint

The ranges of private IPv4 addresses are as folllows: 10.0.0.0 – 10.255.255.255 172.16.0.0 – 172.31.255.255 192.168.0.0 – 192.168.255.255

Hint

A directed broadcast is a message sent to all hosts on a specific network. It is useful for sending a broadcast to all hosts on a nonlocal network. A multicast message is a message sent to a selected group of hosts that are part of a subscribing multicast group. A limited broadcast is used for a communication that is limited to the hosts on the local network. A unicast message is a message sent from one host to another.

Hint

IPv6 LLAs are in the fe80::/10 range. The /10 indicates that the first 10 bits are 1111 1110 10xx xxxx. The first hextet has a range of 1111 1110 1000 0000 (fe80) to 1111 1110 1011 1111 (febf).

Hint

The rules for reducing the notation of IPv6 addresses are: 1. Omit any leading 0s (zeros) in any hextet. 2. Replace any single, contiguous string of one or more 16-bit hextets consisting of all zeros with a double colon (::) . 3. The double colon (::) can only be used once within an address.

Hint

With a network prefix of 48, there will be 16 bits available for subnetting because the interface ID starts at bit 64. Sixteen bits will yield 65536 subnets.

Hint

Prefix 2001:db8::/48 has 48 network bits. If we subnet to a /52, we are moving the network boundary four bits to the right and creating 16 subnets. The first subnet is 2001:db8::/52 the last subnet is 2001:db8:0:f000::/52.

Hint

All the addresses have the part 2001:0DB8:BC15:00A in common. Each number or letter in the address represents 4 bits, so the prefix-length is /60.

Hint

Because only one hexadecimal character is used to represent the subnet, that one character can represent 16 different values 0 through F.

Hint

The EUI-64 process uses the MAC address of an interface to construct an interface ID (IID). Because the MAC address is only 48 bits in length, 16 additional bits (FF:FE) must be added to the MAC address to create the full 64-bit interface ID.

Hint

FF02::1:FFAE:F85F is a solicited node multicast address. 2001:DB8::BAF:3F57:FE94 is a global unicast address. FF02::1 is the all node multicast address. Packets sent to this address will be received by all IPv6 hosts on the local link. ::1 is the IPv6 loopback address. There are no examples of link local or unique local addresses provided.

Hint

IPv6 link-local unicast addresses are in the FE80::/10 prefix range and are not routable. They are used only for communications between devices on the same link.

Hint

Multicast, anycast, and unicast are types of IPv6 addresses. There is no broadcast address in IPv6. Loopback and link-local are specific types of unicast addresses.

Hint

Using stateless address autoconfiguration (SLAAC), a PC can solicit a router and receive the prefix length of the network. From this information the PC can then create its own IPv6 global unicast address.

Hint

SLAAC uses ICMPv6 messages when dynamically assigning an IPv6 address to a host. DHCPv6 is an alternate method of assigning an IPv6 addresses to a host. ARPv6 does not exist. Neighbor Discovery Protocol (NDP) provides the functionality of ARP for IPv6 networks. UDP is the transport layer protocol used by DHCPv6.

Hint

Traceroute uses the ICMP (Internet Control Message Protocol) to send and receive echo-request and echo-reply messages.

Hint

The purpose of ICMP messages is to provide feedback about issues that are related to the processing of IP packets.

Hint

When sending an echo request message, a router will use the IP address of the exit interface as the source IP address. This default behavior can be changed by using an extended ping and specifying a specific source IP address.

Hint

Hint

For the subnet of 192.168.1.64/26, there are 6 bits for host addresses, yielding 64 possible addresses. However, the first and last subnets are the network and broadcast addresses for this subnet. Therefore, the range of host addresses for this subnet is 192.168.1.65 to 192.168.1.126. The other subnets do not contain the address 192.168.1.96 as a valid host address.

Hint

Using the ipv6config command on PC2 displays the IPv6 address of PC2, which is 2001:DB8:1:4::A. The IPV6 link-local address, FE80::260:70FF:FE34:6930, is not used in route tracing. Using the tracert 2001:DB8:1:4::A command on PC1 displays four addresses: 2001:DB8:1:1::1, 2001:DB8:1:2::1 , 2001:DB8:1:3::2, and 2001:DB8:1:4::A.