Networking Basics Module 8 – 11 Checkpoint Test Online

Hint

An IPv4 address is a 32-bit logical address.

Hint

An IP address consists of two parts. The first part is the network number and the second part is the host number. The length of the network number is defined by the subnet mask. For each 255 in the subnet mask, that much of the IP address represents the network part. For each 0 on the right part of the subnet mask, that part of the IP address identifies the host number. In this example the subnet mask of 255.255.255.0 means that 10.10.10.0 is the network number and 2 is the host number.

Hint

The IP addressing system is a hierarchical addressing system. An IP address is made up of two parts: the network address and the host address. For IPv4, the subnet mask is used to identify which portion of an IPv4 address is the network address and which portion is the host address.

Hint

All network devices must have an IP address to communicate on the network. The IP address is used to uniquely identify each device on the network.

Hint

All of the hosts have IP addresses with 192.168.10.__/24 in common. The last digit can be any number in the range from 0 to 255. The first number of the range represents the network number and the last number in the range represents the broadcast address. Hosts can be assigned any number from 1 to 254. The network number in this case is 192.168.10.0

Hint

Two reasons for creating subnets include reduction of overall network traffic and improvement of network performance. Subnets also allow an administrator to implement subnet-based security policies. The number of routers or switches is not affected. Subnets do not simplify network design.

Hint

With the IPv4 address, a subnet mask is also necessary. A subnet mask is a special type of IPv4 address that coupled with the IP address determines the subnet of which the device is a member.

Hint

When a PC does not have a static IP address or cannot pick one up from a DHCP server, Windows will automatically assign the PC an IP address using APIPA, that uses the range of addresses 169.254.0.0 to 169.254.255.255.

Hint

Place the options in the following order:

a link-local address	169.254.1.5
an experimental address	240.2.6.255
a private address	172.19.20.5
a loopback address	127.0.0.1

Hint

The private IP address blocks that are used inside companies are as follows:10.0.0.0 /8 (any address that starts with 10 in the first octet) 172.16.0.0 /12 (any address that starts with 172.16 in the first two octets through 172.31.255.255) 192.168.0.0 /16 (any address that starts with 192.168 in the first two octets)

Hint

Factors that are driving an increase in IPv6 adoption are an increasing internet population, a limited IPv4 address space, issues with NAT and the large number of internet-ready IoT devices.

Hint

IPv6 is designed to be the successor to IPv4. IPv6 has a larger 128 bit address space to provide many more addresses than IPv4.

Hint

IPv4 addressing space is exhausted by the rapid growth of the Internet and the devices connected to the Internet. IPv6 expands the IP addressing space by increasing the address length from 32 bits to 128 bits.

Hint

There are two rules defining how an IPv6 address can be compressed. The first rule states that leading zeros in a hextet can be eliminated. The second rule states that a single :: can be used to represent one or more contiguous all zero hextets. There can be one and only one :: in an IPv6 address.

Hint

There are two rules to help reduce the notation of IPv6 addresses. The first one is to omit any leading 0s (zeros) in any hextet. The second one is that a double colon (::) can replace any single, contiguous string of one or more 16-bit hextets consisting of all zeros, but the double colon (::) can only be used once within an address. If an address has more than one contiguous string of all-0 hextets, the best practice is to use the double colon (::) on the longest string. So, applying the first rule in the IPv6 address we have 2001:db8:0:0:ab00:0:0:0, and applying the second rule results in 2001:db8:0:0:ab00::

Hint

All DHCP messages between a DHCP-enabled client and a DHCP server are using broadcast messages until after the DHCPACK message. The DHCPDISCOVER and DHCPREQUEST messages are the only messages that are sent by a DHCP-enabled client. All DHCP messages between a DHCP-enabled client and a DHCP server use broadcast messages when the client is obtaining a lease for the first time.

Hint

When a DHCP client receives DHCPOFFER messages, it will send a broadcast DHCPREQUEST message for two purposes. First, it indicates to the offering DHCP server that it would like to accept the offer and bind the IP address. Second, it notifies any other responding DHCP servers that their offers are declined.

Hint

The client broadcasts a DHCPDISCOVER message to identify any available DHCP servers on the network. A DHCP server replies with a DHCPOFFER message. This message offers to the client a lease that contains such information as the IP address and subnet mask to be assigned, the IP address of the DNS server, and the IP address of the default gateway. After the client receives the lease, the received information must be renewed through another DHCPREQUEST message prior to the lease expiration.

Hint

Because a DHCP client does not have a valid IPv4 address, it must use a broadcast IP address of 255.255.255.255 as the destination address to communicate with the DHCP server. The DHCPDISCOVER message sent by the client is the first message sent in order to make initial contact with a DHCP server.

Hint

Servers and peripherals are often accessed by an IP address, so these devices need predictable IP addresses. End-user devices often have dynamic addresses that are assigned. Hubs do not require IPv4 addresses to operate as intermediary devices.