University Networks - Assignment 2: Exploring IPv4 Addressing

This assignment solution addresses key concepts in IPv4 addressing. It begins by differentiating between classful and classless addressing, explaining why Class A addresses are often wasted and why organizations might avoid Class C. The solution then explores subnet masks, network addresses, and subnetting, including how the subnet mask differs from the default mask. Network Address Translation (NAT) and its role in address depletion are explained, followed by a comparison of connection-oriented and connectionless services. The solution also covers fragmentation, transition strategies from IPv4 to IPv6 (including tunneling and dual stack), address mapping protocols, and the Internet Control Message Protocol (ICMP). Further, it defines autonomous systems, explains the purpose of Routing Information Protocol (RIP) and Border Gateway Protocol (BGP), and compares distance vector and link state routing methods. The assignment references supporting materials from various sources to provide a comprehensive understanding of the concepts.

Assignment 2

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1. Difference among Classful and Classless addressing
Classless addressing
 It allows utilising of variable Length subnet mask.
 Different subnet masks are utilised in the same network.
 Host or Network id has no limitation (Ding and Du, 2011).
 It is also understood by the name CIDR.
 No default subnet mask is present in classless routing.
Classful addressing
 It divides IP address into the host ID as well as network ID.
 Same subnet mask is utilised in whole network.
2. Reason why most of the addresses in Class A are wasted
A block in the Class A address is too big for almost any firm. It shows that most of the
addresses in Class A are wasted and not utilised (Jara, Zamora and Skarmeta, 2012). A subnet
has 24 bits worth of addressing which is enough for almost 17 million devices individually.
Most of the addresses are remains unused by entities.
A block in the Class C is probably too small for any firm hence they could not provide
addresses to all the clients.
3. Mask in IPV4 addressing
IP address has two parts namely host and network address. Subnet mask separate the IP
address in host and network addresses. Apart from this Subnetting bifurcates the host part of
an IP address into host and subnet address if additional subnetwork is required (Ding and Du,
2011). Subnet mask is understood as 32 bit number which masks an IP address. It is created
by setting all 1’s to network bits and putting all 0’s to host bits. Address “0” is allotted to a
network address while “255” is allotted to broadcast address and is not possible to assign to
hosts. For classed networks some of commonly utilised net masks are Class A has 8-bits,
Class B has 16-bit and Class C has 24-bits.
4. Network address in address block

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First address in a block of address is known as network address. For finding network
addresses, the mask might be ANDed with any random address in a block.
5. Subnetting
Subnetting is a strategy that is used by the company for the partition of single physical
network into multiple smaller logical subnets (Jara, Zamora and Skarmeta, 2012). An IP
address contains a host segment as well as network segment. It is made by taking bits from
the host part of the IP addresses and utilising these bits to assign a number of smaller sub-
networks within the main network. It permits a firm to add sub-networks without the
requirement to obtain a fresh network number by the help of Internet service provider (ISP).
This can be differed by fact that a subnet mask has larger numbers of consecutive 1s as
compared to corresponding default mask.
6. NAT
Network address translation is a method of restructuring one IP address space within another
by making advancements in network address information in the IP header of packets at the
time when they are in transit through a traffic routing device. Mainly the edge routers are
tuned through it (Jara, Zamora and Skarmeta, 2012). This technique was originally utilised as
a shortcut for avoiding the requirement of readdressing every host when a network was
moved.
This helps in IPV4 depletion as it allows users to make static routes to static addresses
permitting the DHCP pool to be freely updated with a smaller exclusion for a smaller range
of IP’s.
7. Difference between connection oriented and connection less services
Network layer uses these two different sorts of services to its precursor layer for data transfer.
Connection-oriented services include the launch and close of the connection while
connection-less services do not need any connection making and finish procedures for data
transfer (TechDifferences, 2017).
8. Fragmentation and its need
Fragmentation is a concept that divides the file into piece so that it can be stored over the disk
easily. It allows storage of files in a non-contiguous way. This is necessary as it allow storing

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the files in an efficient way by making use of memory slots so that performance could be
improved. It makes use of wasted space.
9. Transition from IPv4 to IPv6
It is not possible to have a complete transaction from IPv4 to IPv6 but some of the concept
can be merged with the new technology. At tie of transaction dual stack router is used to have
a communication between both the networks (Naqvi, Siddiqui and Farooq, 2016). It acts as a
medium for the host so that they can access the server without changing the IP address.
Tunnelling on the other hand helps in offering the path over the network through anon
supported IP version.
10. Address mapping protocols
Some of the address mapping protocols is ARP, RARP and ICMP.
 ARP is used for mapping an IP address to a physical address on a local network.
 RARP is used to know the IP address of a machine on a local network.
 ICMP is used to generate error messages to resolve network problem.
11. ICMP and its need
ICMP stands for internet control message protocol that is used for reporting about error
message and also indicating operational information if some host is down or not working. It
is not used by end users instead of that it is used by administrators to troubleshoot the issues
over network (He, 2017). The messages by this protocol are transmitted by the means of
datagrams that contains header as well as original message.
12. Autonomous system
Autonomous system is a network of unit router that runs on a behalf of single administrator.
The autonomous system has a global unique number and is also called as routing domain
(Burgio, Madej and Norton, 2018). It can be said as a system of internet protocol that is
under the control of one or more network.
13. Purpose of RIP

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Routing information protocol is a dynamic protocol that is used for selecting the best routing
route. The purpose of this protocol is used to provide best and shortest path to transfer
message from one location to another (Burgio, Madej and Norton, 2018). The purpose of this
protocol is to assure that data is delivered in a short span of time.
14. Functions of a RIP message
The purpose of RIP message is used by the router to receive the information by requesting it
from an autonomous system. The RIP message also shares the information about the
transaction to their neighbours (Luo, Hu, Wu and Li, 2015). They also use the concept of
hop count to connect directly to any network. Thus, it minimise numbers of hops taken from
source node to destination.
15. OSPF messages propagate faster than RIP messages
It is true that message propagate faster in open shortest path first as compared to RIP
message. It makes the routing efficient and faster as it saves the time of sending request
message. The message is propagated faster via OSPF as they flood the network immediately
(Baker, Al-Dawsari, Tawfik, Reid and Ngoko, 2015). In case of RIP message is distributed
slowly as it relies on periodic update of information.
16. Purpose of BGP
Border gateway protocol is used for managing how packets will be transmitted over the
network (Azharuddin and Jana, 2015). The purpose of BGP is used for connecting one
autonomous system to another. It offers stability over network that allow router to send
packets by adapting a suitable path.
17. Distance vector routing method against link state routing method
The distance vector routing worked over two factors that are distance of the destination and
eth direction of the path. On the other had link state routing requires that all the routers
should know about the path (Sabet and Naji, 2015). Distance vector routing relies upon least
number of hops while link state routing is cost based.

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REFERENCES
Azharuddin, M. and Jana, P.K., 2015. A distributed algorithm for energy efficient and fault
tolerant routing in wireless sensor networks. Wireless Networks, 21(1), pp.251-267.
Baker, T., Al-Dawsari, B., Tawfik, H., Reid, D. and Ngoko, Y., 2015. GreeDi: An energy
efficient routing algorithm for big data on cloud. Ad Hoc Networks, 35, pp.83-96.
Burgio, A., Madej, T.B. and Norton, W.B., Console Connect Inc, 2018. Virtual Router For
Paths Between Autonomous-System Pairs. U.S. Patent Application 15/231,080.
Ding, R. and Du, H., 2011, July. Location-based IP addressing in IP-enable wireless sensor
networks. In Control, Automation and Systems Engineering (CASE), 2011 International
Conference on (pp. 1-4). IEEE.
He, R., 2017, March. Digital campus data grid environment architecture based on IPV6.
In 2017 2nd International Conference on Automation, Mechanical Control and
Computational Engineering (AMCCE 2017). Atlantis Press.
Jara, A.J., Zamora, M.A. and Skarmeta, A., 2012. Glowbal IP: An adaptive and transparent
IPv6 integration in the Internet of Things. Mobile Information Systems, 8(3), pp.177-197.
Luo, J., Hu, J., Wu, D. and Li, R., 2015. Opportunistic routing algorithm for relay node
selection in wireless sensor networks. IEEE Transactions on Industrial Informatics, 11(1),
pp.112-121.
Naqvi, I.F., Siddiqui, A.K. and Farooq, A., 2016, November. IPv6 adoption rate and
performance in the 5G wireless internets. In Region 10 Conference (TENCON), 2016
IEEE(pp. 3850-3858). IEEE.
Sabet, M. and Naji, H.R., 2015. A decentralized energy efficient hierarchical cluster-based
routing algorithm for wireless sensor networks. AEU-International Journal of Electronics
and Communications, 69(5), pp.790-799.
TechDifferences, 2017. Difference Between Connection-oriented and Connection-less
Services. [Online] Available at: https://techdifferences.com/difference-between-connection-
oriented-and-connection-less-services.html. [Accessed on 19th January 2019]

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