IP Address Questions

Question 1

Explanation

IP multicast is a bandwidth-conserving technology that reduces traffic by simultaneously delivering a single stream of information to potentially thousands of corporate recipients and homes.

IP multicast delivers application source traffic to multiple receivers without burdening the source or the receivers while using a minimum of network bandwidth.

Reference: http://www.cisco.com/c/en/us/td/docs/ios/solutions_docs/ip_multicast/White_papers/mcst_ovr.html

Question 2

Question 3

Question 4

Explanation

In order to send traffic to multiple devices (not all) across different subnets we need to use multicast addresses, which are in the range 224.0.0.0 through 239.255.255.255 -> D is correct.

Question 5

Explanation

The RFC 1518 is Classless Interdomain Routing (CIDR), which is created to save the IPv4 addresses because we can now assign IP addresses classless. Therefore, instead of assigning the whole block of a class B or C address, now smaller blocks of a class can be assigned. For example, instead of assigning a whole block of 200.1.45.0/24, a smaller block, like 200.1.45.0/27 or 200.1.45.32/27, can be assigned.

The RFC 1918 is Address Allocation for Private Internets, which reserves IP addresses for private and internal use. These addresses can be used for networks that do not need to connect to the Internet.

Therefore the RFC 1918 is the best choice to “alleviate the depletion of IPv4 public addresses”.

Question 6

Explanation

Only three connection types are commonly known and used in Internet Protocol version four (IPv4) networks: unicast, multicast and broadcast. A fourth connection type, Anycast, was unknown until IPv6 made it a standard connection type. Anycast is not standardized in IPv4 but can be emulated. IPv4 Anycast addressing is a good solution to provide localization for services and servers in order to obtain robustness, redundancy and resiliency.

The basic idea of Anycast is very simple: multiple servers, which share the same IP address, host the same service. The routing infrastructure sends IP packets to the nearest server (according to the metric of the routing protocol used). The major benefits of employing Anycast in IPv4 are improved latency times, server load balancing, and improved security.

Reference: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.116.6367&rep=rep1&type=pdf

Question 7

Explanation

Usually using private IPv4 addresses in a organization is free so surely they are less costly than public IP addresses which you have to buy -> B is correct.

Also we can use private IPv4 addresses to devices that do not need to connect to the Internet because Internet requires public IPv4 addresses -> C is correct.

Answer D is not correct as we still need to use NAT policies to limit which private IPv4 addresses in our company can access our resources.

Question 8

Question 9

Explanation

This is a tricky question if you don’t have a close look on the network. The first octet is 191, not 192 so it belongs to class B, not class C.

Question 10

Question 11

Question 12

Explanation

The Internet authorities have reserved the multicast address range of 01:00:5E:00:00:00 to 01:00:5E:7F:FF:FF for Ethernet and Fiber Distributed Data Interface (FDDI) media access control (MAC) addresses.