Network Communication and Coaxial Cables

This assignment delves into the realm of network communication, particularly examining synchronous systems and their reliance on synchronized clock signals for efficient data transfer. The focus is placed on the advantages of coaxial cables in supporting high-speed transmission due to their inherent ability to carry signals effectively. The analysis utilizes a specific scenario involving GPRS with a transmission rate of 56 to 114 Kbps, demonstrating how coaxial cables can readily accommodate the required data flow.

ABC-Z limited network design
Introduction
Small start-up businesses can have their operations made easy by incorporating networks and
subnetworks in their offices and departments. Having the offices interconnected by a networks makes it
easy to share files, information and even resources such as printers and this will help the business save
on cost and minimize work done manually due to shortage of resources. ABC-Z limited as a small start-
up business setting up business operations on the outskirts of Melbourne CBD will also have easy
operations if it employs a TCP/IP network system to interconnect their computers and other devices. All
their communication problems will be handled by the network and the devices which need to send logs
will send the logs and the logs received immediately from the receivers’ side. There is a great advantage
for using the network to enhance the intercommunication of the devices since the owners will just need
to often check whether the logs are still streaming in.

Question 1
Networking devices can communicate even when they are made by different manufacturers. In their
design, there are reference models applied that allow them to communicate as long as they are
connected and in the same network. These reference models are the Open System Interconnection (OSI)
and the Transmission Control Protocol/Internet Protocol (TCP/IP) [1]. Examples of the TCP/IP protocol
suite in use today include the Dynamic Host Configuration Protocol (DHCP) and the Address Resolution
Protocol (ARP).
The Dynamic Host Configuration Protocol provides its host with all the necessary information for
configuration automatically [1]. The IP address, the subnet mask and the default gateway are all issued
automatically to the host. Bootstrap Protocol (BOOTP) is a protocol used by the Dynamic Host
Configuration Protocol to share its implementation details [2]. The protocol suite contains the Dynamic
Host Configuration Protocol Server where all the hosts acquire TCP/IP configuration information.
Using the Dynamic Host Configuration Protocol makes it easy to move nodes from one subnet to
another since the IP addresses are automatically acquired. In cases where the Dynamic Host
Configuration Protocol suite is not used, the unique unicast IP addresses needed for each node
connected by the TCP/IP model will need manual reconfiguration if a computer is moved from one
computer to another [3]. If a computer is removed from the network, a manual reclamation would be
needed too. The Dynamic Host Configuration Protocol server keeps all the host IP addresses and
dynamically assigns them to hosts automatically when the computer starts on the network. If the
computer stops accessing the network, the IP address is reclaimed automatically by the Dynamic Host
Configuration Protocol server [4].
The host accessing the internet must be DHCP-enabled to allow the Dynamic Host Configuration
Protocol server store its configuration information in a database. The client in turn automatically
receives a valid IP address and the Dynamic Host Configuration Protocol options requested e.g. default
gateway, DNS Servers, and the Domain Name.

Figure 1: Acquisition of an IP address by A DHCP enabled host.
The Address Resolution Protocol on the other hand maps IP network addresses to physical machine
addresses (Media Access Control addresses) that are recognized in the network. The Address Resolution
Protocol suite uses the ARP cache in maintaining the relation between the Media Access Control (MAC)
address with the corresponding IP address by providing the rules to define the relations and doing the
conversions of the addresses [4].
The ARP cache has a big size though it can contain very many computers’ IP addresses if not continually
cleared. This is handled but deleting all the entries of computer addresses saved in the cache which
removes all entries of unused addresses and free spaces. A client therefore caches a give Internet

Protocol (IP) address only for a short time. During the deletion, the ARP cache also deletes all the IP
addresses of computers that are currently not running. This is done by considering all the unsuccessful
attempts to contact the computers.
Figure 2: ARP request-reply structure
The target system also replies with a unicast packet and the IP address. If a computer responds to a
request send to another computer on its behalf, the ARP suite is called Proxy ARP and a gratuitous ARP
occurs when a node defends an Internet Protocol address on the LAN and ensures no other computer
uses the IP address.

Question 2
Besides the OSI model and TCP/IP protocol suite, the User Datagram Protocol (UDP) is also used as a
reference model to networking. In this suite, computers design messages which are called datagrams
and send them to a given host on the network. The User Datagram Protocol normally has no
connections and provides checksums which are useful in confirming the data integrity and port numbers
which address issues arising at the source and destination of the datagrams.
User Datagram Protocol has no dialogues or communications between the host and the server and
therefore information shared via User Datagram Protocol man not have a guarantee of delivery or
duplicate protection. If need arises to handle such errors, UDP introduces other applications such as TCP
to handle them. It is therefore best suited when there is no error checking or correction needed. In the
User Datagram Protocol, a packet is dropped if it delays in delivery [7]. It is therefore good in time saving
since at times it’s better to drop packets and resend rather than wait for a packet that may have been
delayed in the networking.
Question 3
Based on the business requirements for ABC-Z limited, unshielded twisted pair (UTP) will be the best
cable to opt. Being busy, the business will need cables that can overcome any interferences caused by
electromagnetic signals or noise without damaging the information being relayed or delaying it [4]. The
network system is supposed to send logs at pre-defined intervals and this could work perfectly if all
other external factors do not affect the time it takes for the information relayed to reach destination.
The UTP cables are less fragile compared to STP cables and therefore they would suit the company even
in installing them at the high heights and still avoid their damage even when placed at a place where
they are disturbed by other people [4]. The UTP cables use cancellation effect caused by the twisting of
the wire pairs to handle noise and this makes them just sufficient for the use in a company that does not
have much electromagnetic interference.
The unshielded twisted pair cables are smaller than shielded twisted pair and therefore they are easier
to set up and install. They don’t require grounding cables and only need less maintenance and therefore
they are cheaper than shielded twisted pair both in installation and maintenance.

Question 4
To run an application that will transmit data records to another building after every 0.5 seconds, we will
need to use synchronous transmission. This will allow us create agreed timings between which every bit
will be sent over the network. Our system having set times after which the application will transmit data
records to another building, using synchronous transmission, all communication paths will have courier
signals with frequency and bits encoded into a signal.
The synchronous systems normally synchronise signal clocks on both sides before beginning
transmissions. supports high data transfer rate They will therefore need a clock signal between the
sender and the receiver and require a requires master configuration with a slave. The sender and
receiver all have some internal circuits to allows them regulate data access to hosts whose follow that
agreement.
A coaxial cable with give the best speed of transmitting and supporting the types of connection due to
its high speed in carrying the signal [6]. Using the General Packet Radio System (GPRS), we will have a
speed of 56 to 114 Kbps. One record will be coming every 0.5 seconds and records are 500 bytes in
length an equivalent of 4000bits or 4Kbs. The coaxial cable will therefore be able to hold all the bytes
with no expected delays.

References
[1] S. C. F. Behrouz A. Forouzan, Data Communications and Networking, McGraw-Hill Higher
Education, 2003.
[2] R. Droms and T. Lemon, The DHCP Handbook, SAMS Publishing, 2003.
[3] R. Droms, " Dynamic Host Configuration Protocol (DHCP) and Bootstrap Protocol (BOOTP)
Parameters," 17 11 2016. [Online]. Available: http://www.iana.org/assignments/bootp-dhcp-
parameters/bootp-dhcp-parameters.xhtml. [Accessed 26 August 2017].
[4] A. Bernard and C. Stuart, "Dynamic Host Configuration Protocol (DHCP) Domain Search Option,"
November 2002. [Online]. Available: https://tools.ietf.org/html/rfc3397. [Accessed 26 August
2017].
[5] B. A. Forouzan, TCP/IP Protocol Suite (McGraw-Hill Forouzan Networking) 4th Edition, 2009.
[6] Forouzan, TCP/IP Protocol Suite e/4, 2010.
[7] M. Clark, Data Networks IP and the Internet,, West Sussex, England: John Wiley & Sons Ltd, 2003.
[8] I. Cisco Systems, "CCNA: Network Media Types," 14 March 2003. [Online]. Available:
http://www.ciscopress.com/articles/article.asp?p=31276. [Accessed 28 August 2017].
[9] C. C. A, "STP vs UTP Cables: Application Comparison," 7 02 2010. [Online]. Available:
https://customcable.ca/stp-vs-utp-cables-application-comparison/. [Accessed 27 08 2017].
[10] C. B. J. B. L. E. L. d. A. R. Bates, "High speed electrical transmission line design and characterization,"
30 09 1986. [Online]. Available:
http://iopscience.iop.org/article/10.1088/1748-0221/12/02/C02002/pdf. [Accessed 27 08 2017].