HNC Computing: Computer System Architecture Troubleshooting

This report delves into computer information systems, addressing various troubleshooting scenarios related to network performance, connectivity, and hardware/software issues. It explores the use of Media Access Control (MAC) and IP addresses in network communication, detailing the functions of network devices like bridges, hubs, switches, and routers. The report also discusses different network topologies, including bus, ring, star, hybrid, and mesh topologies, contrasting physical and logical arrangements. Furthermore, it compares the OSI and TCP/IP models, outlining the layers and protocols involved in each. The document also identifies hardware and software components essential for network connectivity, such as servers, clients, transmission media, and network interface cards. Finally, it provides practical methods for managing hardware and software assets, improving computer system effectiveness, and addressing common technical problems in network environments. This document is shared on Desklib, where students can find a wealth of study resources, including past papers and solved assignments.

Computer Information System
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Contents
Computer Information System....................................................................................................................1
Question 1...................................................................................................................................................2
Question 2...................................................................................................................................................3
Question 3...................................................................................................................................................5
Question 4...................................................................................................................................................7
Question 5...................................................................................................................................................8
Question 6...................................................................................................................................................9
Question 7.................................................................................................................................................10
References.................................................................................................................................................13
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Question 1.
There are nodes in any network, every node has Media Access Control address which is also
known as the hardware address and an IP address which is also called as Network address. These
addresses are stored in IP stack of that node.
1. MAC address
It is a 48 bit address which is basically runs in the Read Only Memory of the Network
Interface Card. The format of these address is,
MM:MM:MM:SS:SS:SS
MM-MM-MM-SS-SS-SS
Here, the starting 3 bytes are defined as the vendor numbers and the last 3 bytes are the NIC
serial numbers.
2. IP address
IP addresses are usually 32 bit long or 128 bit long. The Internet Protocol addresses are
unique and are called as local host which is usually reserved for each and every computer
internally.
They are defined according to the geographic location of a machine.
A network works with a combination of Media Access Control address and Internet Protocol
address. The local networks are based on MAC address and Internet Protocol address works on
the top levels of the Open System Interconnection model. Basically, an IP packet endures within
an Ethernet packet (Microsoft, 2017).
As Ethernet packet only holds up to 1500 bytes. With a combination of IP packet, the size of an
Ethernet frame can hold up to 1514 bytes.
There are several devices which are used to filter the traffic of the network and are known as
connecting devices. These devices use both physical addresses as well as logical addresses.
These devices are also responsible for connectivity between different types of networks and for
providing hierarchical addressing (Anttalainen, 2015). Some of these devices are,
1. Bridge
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A bridge is responsible for forwarding the data on a network based on the physical address. They
function at the Network Layer in the Transport Control Protocol/Internet Protocol heap.
2. Hub
In a hub, the network cables are connected to make up a network segment. These devices do
not filter up the data, but they transfer the data packets to different frames of a network.
These days each computer is connected to a hub with the help of a single line. Hence, adding
a host to any network gets easy.
3. Switch
Switch works particularly on the address and is responsible for forwarding the data frames to
the correct ports. On a switch, again the computer is connected through a single line.
4. Router
The main functionality of a router is to filter the data and then forward it on the basis of
logical address or the IP address. They make the network effective and efficient and controls
the traffic on the network (Schneidewind, 2016).
Question 2.
There are two types of network topologies i.e. physical topology and logical topology.
Physical topology depicts the way a network is expend physically. The way devices are
connected by wires or any media. The links in together form a topology. On the other hand,
logical topology represents the way in which the data is taken care of in a network. It also
indicates the way hosts access the physical topology to send data or the flow of data in a
network (Broadhurst, 2017).
The different types of logical topology are:
1. Bus topology
2. Ring topology
The different types of physical topology are:
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1. Star network topology
2. Hybrid topology
3. Mesh network topology
In this topology, each and every device have point-to-point link to every other device. This
topology eliminates the problems of traffic in case the links are shared by more than one device
i.e. by multiple devices. It is also reliable and secure. The fault identification and fault isolation
is easy too. But this topology requires a high amount of cabling and the hardware are very
expensive.
4. Bus network topology
In bus network topology the cable sections are connected linearly. This topology uses 10Base5
cabling standard. They are easy to install and are cheap in cost. They are a good choice for small
networks. The disadvantages of this topology include difficult connection and fault isolation.
They are also difficult to troubleshoot.
5. Ring network topology
In this topology, each and every device is connected point-to-point but their can be only two
devices on either side. It also consists of a repeater. The advantages of this topology is it is
efficient under heavy network load. It can also manage the connectivity between the computers
without a network server. The disadvantages include, that the network adapter cards are very
expensive also any sort of moves or changes of devices effects the whole network (Robertazzi,
2015).
6. Point to point topology
The basic difference between logical and physical topology are:
1. Logical topology describes the way signals moves from one node to another node while
physical topology shows how the devices are connected or the nodes are connected to
each other.
2. Logical topology decides the network access and physical topology decides the
connections.
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Question 3.
The Open Systems Interconnection was developed by the International Organization of
Standardization. While the Transport Control Protocol/Internet Protocol (TCP/IP) model was
developed by US Defense Advance Research Projects Agency (DARPA).
The OSI model consists of 7 layers. They are described as below,
1. Physical Layer (Layer 1)
This layer is responsible for transferring of data at the wire level. This layer is responsible for
handling the encoding and decoding of data regardless of the networking medium. Few
examples include IEEE 802.11 and Synchronous optical networking i.e. SONET (Wetteroth,
2017).
2. Data Link Layer (Layer 2)
This layer is basically responsible for link installation along with its termination, sequencing,
error checking, traffic control and media access management. The standards which are used
at this layer are Media Access Control and Logical Link Control.
3. Network Layer (Layer 3)
At this layer, the routing of the network takes place. This layer provides fragmentation and
logical addressing and decides the traffic routing. This layer uses Internet Protocol along with
Internet Group Message Protocol and Internet Control Message Protocol.
4. Transport Layer (Layer 4)
As the name suggests, transport layer’s functionality is to segment the message, multiplex the
session, control the traffic and then acknowledge it. This layer provides a reliable message
channel and operates error detection and correction functions. Transport Control Protocol and
User Datagram Protocol are the protocols of this layer.
5. Session Layer (Layer 5)
The main functionality of this layer is session establishment along with its maintenance and
termination. Few of the examples of this layer are Named Pipes and NetBIOS.
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6. Presentation Layer (Layer 6)
The main functionality of this layer is of translating the character code, encryption along with
data conversion and compression. Few of the examples of this layer are Secure Sockets Layer,
Multipurpose Internet Mail Extensions and Transport Layer Security.
7. Application Layer (Layer 7)
This layer is responsible for resource sharing, remote printer, remote file access and electronic
messaging. The common protocols of this layer are File Transfer Protocol, Hypertext Transfer
Protocol, Domain Name Service and Simple Mail Transfer Protocol.
TCP/IP Model:
The Transport Control Protocol/Internet Protocol model is also layered and is has more
implementation. There are four layers in this model which are described below,
1. The Link Layer
This layer is the lowest layer and is also known as network interface layer. The main
functionality of this layer is to frame physical network functions like error detection, line coding
and modulation. The main protocols of this layer are Neighbor Discovery Protocol (NDP), IEEE
802.11 and Address Resolution Protocol (ARP).
2. The Internet Layer
This layer is cooperated with the network layer of the Open System Interconnection model and
functions same as the network layer. The protocols include ICMP, IP and IGMP.
3. The Transport Layer
This layer works same as the transport layer of the OSI model and functions in the same way.
The protocols include Transport Control Protocol and User Datagram Protocol.
4. The Application Layer
This is the top most layer of the TCP/IP model and works same as the session, presentation and
application layer of the OSI model. This layer handles the process-to-process communication
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functions. Hence, it is responsible for character code translations, compression, encryption,
electronic messaging and many more things. The protocols of this layer include Named Pipes,
TLC, FTP, HTTP, SMTP, etc (Fall, 2016).
Question 4.
The convenient hardware and software systems to form or to configure computer based network
connectivity are described as follows,
1. Servers
These are basically the computers which are responsible for holding the programs, shared
files and the operating system. The types of servers include, database servers, mail servers,
fax servers, file servers, etc.
2. Clients
These are the main functioning computers which makes use of the shared network resources.
They request a service from the server and the server responds back to them.
3. Transmission Media
These are the media or cables which connects the computers to several devices and to the
network. They are also called channel links. Few of the examples include, twisted-pair cable
or a copper cable.
4. Printers and other peripherals
These are the hardware resources which are used by the users of the network. These includes
printers, software, mouse, keyboard, etc.
5. Network Interface Card
This is a software resource which send and receives data. It also controls the data flow
between networks and computers. It works on the physical layer of OSI model (Odom,
2015).
6. Hub
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In hub, multiple computers are connected to each other through a single center point. This single
point is the hub.
7. Router
Routers are used to connect the computer systems to the Local Area Networks or to a internet connection
(Cisco, 2017).
Question 5.
It has become very difficult to manage a computer hardware and software. Some of the ways by
which management of hardware and software assets gets easy are described below,
1. Tracking hardware and software resources:
It is a good practice to track the performance of the hardware and the software resources. They
should be changed time-to-time in case they need replacement.
2. Software Distribution
Mostly challenges are faced at distributing the new software. Due to this, there are high chances
of virus or operating system patches. In these cases, its better to adapt a good network
distribution system and update all the existing software. Remove all the outdated and
unauthorized software’s from all the computer systems (McMillan, 2012).
3. Technical help desk support
There should be a technical help desk support in case anything goes out of scope of the IT
professional. There should be more options for access of information and remote control of
mobile devices and the computer systems. A management tool can be used which will allow
the staff of help desk to control the system remotely and find the problem and then
troubleshoot it.
4. Image Updating, Retiring Migration and Assets
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A management tool can be used which will automatically update all the systems and will work as
a global operating system for the entire computer systems. Along with this, proper tools should
be installed which will protect the system from any kind of viruses (Bird, 2016).
Question 6.
There are many ways by which the effectiveness of the computer system can be improved. Some
of them are described below,
1. Reduce the number of applications which run on the startup of the computer system.
2. Remove or uninstall the programs and application which are no longer required in the
system.
3. From time to time, do clean up your drive or disk.
4. Switch from Internet Explorer to Google Chrome as Chrome has less bugs than Internet
Explorer. The efficiency of Google Chrome is also better than Internet Explorer.
5. Run a scan test and check if there are any sort of malwares or viruses. And remove them.
6. Check for spywares as well and remove them from the computer system.
7. Choose an option which says “adjust for best performance” from the system properties.
8. Defrag the drive I.e. schedule an action to defragment the drive. This will make the
system better as it removes downloaded files which are not in use along with the
programs which are of no use.
9. Add more RAM memory as it will increase the capacity of the computer system.
10. Make sure to upgrade to SSD drive, they will make the computer system faster. They are
expensive and also have less capacity, but they increase the productivity (McCue, 2017).
Question 7.
1. Network Performance lower than baseline
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These types of problems occur at the lower layer of the OSI model. To troubleshoot this
problem, collect the baseline data and update the baseline document in time. Install an IP/MAC
database to keep a track of baseline documents (Colasoft, 2018).
2. Loss of connectivity
Loss of connectivity can happen due to several reasons, it can be due to problems at the physical
layer or at the network layer of the OSI model. This problem can occur due to modem and router
issues, to solve this problem first check whether a green light is flashing on the router or not. If
not turn it off and turn it on again and check all the network connections. Some of the wires
might get loosed up. We can also perform a factory reset on the router so that its firmware can
get upgraded. Sometimes it can be a DNS network problem which will be solved by calling the
Internet Service Provider (TechRepublic, 2015).
3. Network bottlenecks or congestion
To reduce the network congestion, make use of a content delivery network as it provides global segregation
of static content. One can also reconfigure the TCP/IP settings as sometimes the data might not get
processed. One of the latest technique used is backpressure routing i.e. when the capacity of one network
reaches the capacity, the other network route can also be used for transmission of data. Make a proper use
of network redundancy and prioritize the network traffic as per the requirements (Rivenes, 2017).
To reduce the network bottlenecks, load the balancing on the data on the network or make
use of internet load sharing. Apart from this, one can optimize their WAN and can use
software optimization tools. A new technique known as port channeling has come into
picture to reduce bottlenecks as it combines multiple physical links together. As a result, the
bandwidth and performance of the computer system increases. These problems occur at the
network and data link layer of the OSI model (Froehlich, 2017).
4. High CPU utilization
One can easily check which resources are utilizing the CPU mostly from the “Task Manager”
of the system. Figure out which resources are using unnecessarily and eliminate them from
the system. Many tools also exist in the market which monitors the resource utilization for
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e.g. Performance monitoring log provides a list of all such resources and then dumps them or
make their utilization less. These problems are faced at almost every layer of the OSI model
(Gray, 2014).
5. Console error messages
Most of the times errors in the browser are logged at the console and are considered as the console error
messages. The console helps in determining whether a browser page is working fine or not. The error
message on the console depicts that an unresolved failure has occurred in the page. The errors can be seen
by a developer in the console by typing console.error(). Tools like Chrome DevTools tracks the root cause
of these errors. The developers can check the complexity of the error and then can fix them accordingly by
using try and catch statements explicitly. These types of errors mostly occur at the application layer of the
OSI model (Sub, 2017).
6. Network failure
Network failure takes place at the physical layer or at the network layer of the OSI model.
The following are the ways by which the network failure problems can be troubleshoot.
i. Check the ethernet cables, they should be connected at both ends and the ports should
be enabled,
ii. Check the cables properly for any sort of damage in the cable.
iii. Check the router significance, whether the cables are supported by the router or not.
iv. Verify the adapter along with the router.
v. Check the TCP/IP settings, they should be configured correctly.
vi. There can be a security mismatch as well i.e. the end user’s computer system must
support the security mode of the router. If they mismatch, there will be a mismatch in
the network connection.
7. Suboptimal performance
The suboptimal performance problems are caused due to many reasons like poor query plans,
contention for database or long application processing times or may be a bad system design. To
solve these problems first check the application and the server. Tools like application profiling
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tools help in determining the processing time of the end user. If any time difference is
determined between different types of requests from the connection, then its sure that the
problem is in the client application. These errors also occur at the application and presentation
layer of the OSI model (Withers, 2016).
8. Access Issues
There are many types of access issues for example, file access, internet access, database access
and many more. If a user has network access issues then follow the following steps to resolve it,
i. Check the internet connection.
ii. Check if their any proxy in the operating system or in the browser.
iii. The firewall and the software are configured properly.
iv. Check the network settings of the computer system.
To solve the file sharing access problems,
i. Check the sharing settings of the computer system and the browser.
ii. Make use of tools like Windows Repair and Diagnostics Tool.
iii. Make sure the firewall status is active and all the settings are configured correctly.
iv. Restart the network.
v. The last option is to reboot the system.
References
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Anttalainen, T. (2015). Introduction to Telecommunications Network Engineering. Norwood: Artech
House.
Bird, D. (2016). Network+ training guide. 5th ed. Indianapolis, IN: Que.
Broadhurst, T. (2017). Difference between physical & logical topology. [online] Available at:
https://prezi.com/opqbxpcssv5m/difference-between-physical-logical-topology/ [Accessed 7
Apr. 2019].
Colasoft (2018). How to Baseline Network Throughput and Performance - Colasoft. [online]
Available at: https://www.colasoft.com/nchronos/network-baseline.php [Accessed 8 Apr.
2019].
Cisco (2017). Networking Basics. [online] Available at:
https://www.cisco.com/c/en/us/solutions/small-business/resource-center/networking/
networking-basics.html [Accessed 7 Apr. 2019].
Fall, K. (2016). TCP/IP illustrated. Upper Saddle River, NJ: Addison-Wesley.
Froehlich, A. (2017). 4 Ways To Ease Network Bottlenecks. [online] Available at:
https://www.networkcomputing.com/data-centers/4-ways-ease-network-bottlenecks[Accessed
8 Apr. 2019].
Gray, G. (2014). Troubleshooting High CPU Utilization. [online] Available at:
https://www.itprotoday.com/cloud-computing/troubleshooting-high-cpu-utilization[Accessed
8 Apr. 2019].
McCue, T. (2017). 12 Tips for Increasing Computer Speed. [online] Available at:
https://smallbiztrends.com/2014/06/how-to-increase-computer-speed.html[Accessed 8 Apr.
2019].
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McMillan, T. (2012). Cisco networking essentials. Indianapolis, Ind: Wiley.
Microsoft (2017). Why use hardware addresses?. [online] Available at:
https://support.microsoft.com/en-us/help/4027925/windows-how-and-why-to-use-random-
hardware-addresses [Accessed 6 Apr. 2019].
Odom, W. (2015). Computer networking first-step. Indianapolis, IN: Cisco Press.
Rivenes, L. (2017). You can't avoid network congestion, learn how you can reduce it. [online]
Available at: https://datapath.io/resources/blog/10-ways-to-reduce-network-congestion/
[Accessed 8 Apr. 2019].
Robertazzi, T. (2015). Basics of computer networking. New York: Springer.
Schneidewind, N. (2016). Computer, network, software, and hardware engineering with applications.
Hoboken, NJ: John Wiley and Sons.
Sub, M. (2017). Troubleshooting Console Log Errors. [online] Discord. Available at:
https://support.discordapp.com/hc/en-us/articles/115001239472-Troubleshooting-Console-
Log-Errors[Accessed 8 Apr. 2019].
TechRepublic (2015). PC user's troubleshooting guide. Louisville, KY: Tech Republic.
Wetteroth, D. (2017). OSI reference model for telecommunications. New York: McGraw-Hill.
Withers, S. (2016). 10 ways to improve network performance | ZDNet. [online] Available at:
https://www.zdnet.com/article/10-ways-to-improve-network-performance/ [Accessed 7 Apr.
2019].
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