IFSM – Final Assessment Essay
The final assessment is a five-question essay assignment. Your answers to all questions should be complete and demonstrate your understanding of ALL of this semesters lessons. Each answer should be 3-5 paragraphs in length. MUST INCLUDE APA in-text and bibliography citations!!
Question 1: Explain the differences between the following network devices: hub, bridge, switch, router, firewall. Where would you utilize each device and why? Where does each device reside within the OSI model?
Question 2: Define what VPNs are and used for. Distinguish hardware VPN devices and appliances from software devices. Give examples of both. How do VPNs work? Why would one use a VPN? What are the downsides of using VPNs?
Question 3: Describe four wireless technologies/standards. Describe what each one does and briefly how it works? How is each one different from the other standards? Why would you use one over the other?
Question 4: Describe what cloud computing is. Describe the three cloud computing models. Discuss why and when you would utilize each model. Give examples.
Question 5: Describe in detail what the Internet of Things (IoT) is. What are the issues with IoT? Do you believe IoT is the wave of the future (yes or no, and why)? How will IoT impact the overall internet?
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Assignments Project 5: Final Assessment
Project 5: Final Assessment
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Rubric Name: Final Assessment
IFSM 370 6381 Telecommunications in Information Systems (2
Before you start working on this assignment, please read (i) Project Instructions; and
(ii) Grading Rubric, with attention. These items are posted below.
Criteria Level 3 Level 2 Level 1
Question
1
/ 3.5
Question
2
/ 3.5
3.5 points
Answer demonstrates a
complete understanding of the
course concepts, analysis, and
critical thinking. Answer is
complete, with sufficient detail
and examples. Answer is
written in students own voice
and not simply copied and
pasted from another source.
Lacking sufficient
detail/examples.
2 points
Answer demonstrates that
student does not have a
complete understanding of
course concepts, analysis,
and/or critical thinking.
Some content is
copied/pasted from another
sourcenot in the students
own words. Lacking
sufficient detail/examples.
0 points
Answer is missing or
displays a complete
lack of
understanding of
the material. Entire
answer copied from
other source.
3.5 points
Answer demonstrates a
complete understanding of the
2 points
Answer demonstrates that
student does not have a
0 points
Answer is missing or
displays a complete
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Total / 20
Question
3
/ 3.5
Question
4
/ 3.5
Question
5
/ 3.5
Reference
Sources
/ 2.5
course concepts, analysis, and
critical thinking. Answer is
complete, with sufficient detail
and examples. Answer is
written in students own voice
and not simply copied and
pasted from another source.
complete understanding of
course concepts, analysis,
and/or critical thinking.
Some content is
copied/pasted from another
sourcenot in the students
own words. Lacking
sufficient detail/examples.
lack of
understanding of
the material. Entire
answer copied from
other source.
3.5 points
Answer demonstrates a
complete understanding of the
course concepts, analysis, and
critical thinking. Answer is
complete, with sufficient detail
and examples. Answer is
written in students own voice
and not simply copied and
pasted from another source.
2 points
Answer demonstrates that
student does not have a
complete understanding of
course concepts, analysis,
and/or critical thinking.
Some content is
copied/pasted from another
sourcenot in the students
own words. Lacking
sufficient detail/examples.
0 points
Answer is missing or
displays a complete
lack of
understanding of
the material. Entire
answer copied from
other source.
3.5 points
Answer demonstrates a
complete understanding of the
course concepts, analysis, and
critical thinking. Answer is
complete, with sufficient detail
and examples. Answer is
written in students own voice
and not simply copied and
pasted from another source.
2 points
Answer demonstrates that
student does not have a
complete understanding of
course concepts, analysis,
and/or critical thinking.
Some content is
copied/pasted from another
sourcenot in the students
own words. Lacking
sufficient detail/examples.
0 points
Answer is missing or
displays a complete
lack of
understanding of
the material. Entire
answer copied from
other source.
3.5 points
Answer demonstrates a
complete understanding of the
course concepts, analysis, and
critical thinking. Answer is
complete, with sufficient detail
and examples. Answer is
written in students own voice
and not simply copied and
pasted from another source.
2 points
Answer demonstrates that
student does not have a
complete understanding of
course concepts, analysis,
and/or critical thinking.
Some content is
copied/pasted from another
sourcenot in the students
own words. Lacking
sufficient detail/examples.
0 points
Answer is missing or
displays a complete
lack of
understanding of
the material. Entire
answer copied from
other source.
2.5 points
At least two references are
appropriately incorporated and
cited, using APA style for each
question.
1 point
One references are
appropriately incorporated
and cited, using APA style
for each question.
0 points
Missing references
from each question.
Submit Cancel
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Level 1
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Assignments Project 5: Final Assessment
Project 5: Final Assessment
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Instructions
Due Date
Jul 14, 2020 11:59 PM
Attachments
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Hide Rubrics
Rubric Name: Final Assessment
IFSM 370 6381 Telecommunications in Information Systems (2
Before you start working on this assignment, please read (i) Project Instructions; and
(ii) Grading Rubric, with attention. These items are posted below.
Criteria Level 3 Level 2 Level 1
Question
1
/ 3.5
Question
2
/ 3.5
3.5 points
Answer demonstrates a
complete understanding of the
course concepts, analysis, and
critical thinking. Answer is
complete, with sufficient detail
and examples. Answer is
written in students own voice
and not simply copied and
pasted from another source.
Lacking sufficient
detail/examples.
2 points
Answer demonstrates that
student does not have a
complete understanding of
course concepts, analysis,
and/or critical thinking.
Some content is
copied/pasted from another
sourcenot in the students
own words. Lacking
sufficient detail/examples.
0 points
Answer is missing or
displays a complete
lack of
understanding of
the material. Entire
answer copied from
other source.
3.5 points
Answer demonstrates a
complete understanding of the
2 points
Answer demonstrates that
student does not have a
0 points
Answer is missing or
displays a complete
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6/9/2020 Project 5: Final Assessment – IFSM 370 6381 Telecommunications in Information Systems (2205) – UMGC Learning Management System
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Total / 20
Question
3
/ 3.5
Question
4
/ 3.5
Question
5
/ 3.5
Reference
Sources
/ 2.5
course concepts, analysis, and
critical thinking. Answer is
complete, with sufficient detail
and examples. Answer is
written in students own voice
and not simply copied and
pasted from another source.
complete understanding of
course concepts, analysis,
and/or critical thinking.
Some content is
copied/pasted from another
sourcenot in the students
own words. Lacking
sufficient detail/examples.
lack of
understanding of
the material. Entire
answer copied from
other source.
3.5 points
Answer demonstrates a
complete understanding of the
course concepts, analysis, and
critical thinking. Answer is
complete, with sufficient detail
and examples. Answer is
written in students own voice
and not simply copied and
pasted from another source.
2 points
Answer demonstrates that
student does not have a
complete understanding of
course concepts, analysis,
and/or critical thinking.
Some content is
copied/pasted from another
sourcenot in the students
own words. Lacking
sufficient detail/examples.
0 points
Answer is missing or
displays a complete
lack of
understanding of
the material. Entire
answer copied from
other source.
3.5 points
Answer demonstrates a
complete understanding of the
course concepts, analysis, and
critical thinking. Answer is
complete, with sufficient detail
and examples. Answer is
written in students own voice
and not simply copied and
pasted from another source.
2 points
Answer demonstrates that
student does not have a
complete understanding of
course concepts, analysis,
and/or critical thinking.
Some content is
copied/pasted from another
sourcenot in the students
own words. Lacking
sufficient detail/examples.
0 points
Answer is missing or
displays a complete
lack of
understanding of
the material. Entire
answer copied from
other source.
3.5 points
Answer demonstrates a
complete understanding of the
course concepts, analysis, and
critical thinking. Answer is
complete, with sufficient detail
and examples. Answer is
written in students own voice
and not simply copied and
pasted from another source.
2 points
Answer demonstrates that
student does not have a
complete understanding of
course concepts, analysis,
and/or critical thinking.
Some content is
copied/pasted from another
sourcenot in the students
own words. Lacking
sufficient detail/examples.
0 points
Answer is missing or
displays a complete
lack of
understanding of
the material. Entire
answer copied from
other source.
2.5 points
At least two references are
appropriately incorporated and
cited, using APA style for each
question.
1 point
One references are
appropriately incorporated
and cited, using APA style
for each question.
0 points
Missing references
from each question.
Submit Cancel
6/9/2020 Project 5: Final Assessment – IFSM 370 6381 Telecommunications in Information Systems (2205) – UMGC Learning Management System
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Overall Score
Submit Assignment
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(0) file(s) to submit
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Comments
Level 3
18 points minimum
Level 2
15 points minimum
Level 1
11 points minimum
Level 0
0 points minimum
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Module 4: Telecommunications and Network Planning, Design, and Management
Commentary
Topics
1. Telecommunications and Network Design Strategies
2. Logical and Physical Diagrams
3. Network Planning
1. Telecommunications and Network Design Strategies
Designing telecommunications networks requires methodical procedures and strategies by design engineers and managerial stakeholders. First and
foremost, the outcome of the design must support business objectives and goals. Understanding the design requirements is most important prior to
designing the enterprise networks. Management has its business goals to achieve, and the network must support the business operations. Therefore,
network designers must communicate and accurately translate the design requirements to network engineers to design and implement the network
accurately and properly to support business objectives.
A. Layering, Layered Network Architectures, and Multiplexing Physical and Virtual Connections
Device-based multiplexing provides benefits for co-located or closely located devices that can share a single transmission medium. In short, this type
of multiplexing consists of the physical connection of multiple devices with virtual point-to-point connections between pairs of devices. Software-based
multiplexing, on the other hand, is what makes computer networking possible. Networking differs from simple multiplexing in that it provides virtual
connections between large numbers of devices over multiple shared physical connections.
Figure 4.1
Multiplexing
Specifically, networking is rooted in statistical time-division multiplexing (STDM or statistical TDM, also known more simply asstatistical multiplexing).
In STDM, each block of data transmitted over the physical connections is preceded by control information that determines the device or port to which
the receiver delivers the data. Similarly, in networking, each block of data transmitted over the physical connections is preceded by control
information that helps the receiving device determine what to do with the data. The control information consists of a channel number or virtual
connection identifier (VCI). Depending on which packet switching technology is used, the virtual connection is configured and routed differently.
B. Virtual Ports and Devices
Once you have made the leap to the concept of virtual connections, as in STDM, you do not have to go much further to accept the possibility of having
multiple virtual connections in a single physical device and sharing the connection hardware as well as the transmission hardware. A PC on a LAN may
have only one physical networking port that is connected to only one physical wire, but when loaded with appropriate software, the PC may be
maintaining active virtual data connections with many other machines on the network, apparently simultaneously. All virtual connections are kept
separate from each other because each is assigned to a virtual port with associated tables of control data that are updated based on the contents of
the control information in the header of each received block.
Keeping all of this straight requires fairly complex software. Initially, complex networking subsystems were built to address networking unique to each
implementation. The developers who built these early subsystems had to be highly skilled in many areas (these areas correspond to the layers in the
layered architecture) to address this level of complexity.
When faced with a complex problem, a good system designer tries to break the problem into small, simple pieces that are easier to comprehend. Using
this approach, which is sometimes referred to as modularization or divide-and-conquer, the data is hidden with a module, and each module or group of
modules has an implementation secret, which means that the details of how the module performs its task are not public. The internal data structure
and the algorithm used, for example, are thereby hidden from the calling modules, hence the name information hiding. The advantage to such an
approach is that these details can be changed without modifying the calling modules. This is also called information hiding, and supports the concept of
divide-and-conquer.
Similarly, the approach used for communications and networkingusing a layered architecture for the communications subsystem or networkapplies
the divide-and-conquer approach to the problem of transferring data reliably and quickly. Each layer of the architecture, just like each module of a
complex system, needs to have a well-defined job of manageable size for this approach to work.
The following basic principles apply to a layered communications architecture:
In general, a layer is a piece of software or hardware, or a combination of the two.
Each sender layer communicates control information to its matching receiver layer via an agreed-upon protocol.
A sender layer requests services from the next (sending) layer below it in the protocol stack.
A receiver layer delivers a communicated entity to the (receiving) layer directly above it.
Layers are functionally independent. The choice of a protocol at one layer should not affect layers above or below it.
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A layer may be null if it is not required for the full interconnection session. When a layer is null, that means that no attempt is made to provide
the services that this layer should provide.
Each layer in a layered architecture introduces the need for more overhead in transmission. By networking overhead, we mean those bits in the data
transmission that do not appear in the original data input into the protocol stack by the user/application. The concept of layered architecture is similar
to that of an envelope within an envelope. If designers and implementers are willing to tolerate a large amount of overhead, there must be some
benefit to offset the accompanying large costand there is. A layered architecture provides a great deal of functional modularity. If the architecture is
properly designed, making changes to one module (at one layer) does not have a ripple effect on the operation of other layers (modules). Other less
obvious benefits are associated with the reduced complexity of standard specifications and development based on smaller modules.
The layers in network architectures are structured in several different ways. For all such architectures in use today, the closer you are to the bottom of
the protocol stack, the more hardware-oriented you are, and the more standardized the hardware is.
The key to a layered architecture is the concept that each module/layer communicates with only three other entities, as shown in figure 4.2:
1. the layer/module above it in the protocol stackfor service information for the current layer and data
2. the layer/module below it in the protocol stackfor service information for the subsidiary layer and data
3. its logical peer layer/module in the protocol stack on the remote hostfor data and control specifications
Figure 4.2
Layered Protocol Stacks
D. The Open Systems Interconnection (OSI) Model
The Open Systems Interconnection or OSI model, developed by the International Organization for Standardization (ISO) and thus international in
scope, is the logical structure on which to base the discussion and standardization of data communications. For more on the OSI model,
see http://www.inetdaemon.com/tutorials/basic_concepts/network_models/osi_model. It is a layered communications architecture consisting of seven
layers:
Figure 4.3
OSI Model
OPEN SYSTEMS INTERCONNECTION (OSI)
OSI Welcome
Welcome to the Open Systems Interconnection (OSI) model. In this presentation, you will learn about
the seven layers of the OSI model and the security issues at each layer.
You will begin by clicking on the OSI Overview button on the top left. After you read some general
information about the model, be sure to click on the Information Assurance tab to read about the five
pillars of information assurance, as this topic forms the basis of the discussion about security concerns
and issues at each layer.
Next, you will investigate each layer. You will do this by selecting the names of the layers from the menu
on the left. When you click on a layer, you will see two tabs: Description and Information Assurance.
These tabs will lead you to information about the layer and its associated security issues.
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The layers are numbered from a communication’s viewpoint in that the first layer, physical, is the one that actually reaches out and touches the
communications environment. You can read more about each layer’s functionality by clicking on each layer in figure 4.3.
But what does open systems interconnection model mean? The model allows different utilities and protocols the ability to communicate together. For
example, an e-mail sent from one mail system such as Hotmail will be delivered to a Gmail account in a user-readable format. The current OSI
environment seems to have been significantly expanded with an emphasis on open systems. The objective has been widened to include any computer
and/or process that has been designed according to a set of open system specifications (some of which are national and international standards, others
of which are proprietary standards where the sponsor has made them open). When a standard is “open,” it is made publicly available and has various
rights to use associated with it. TCP/IP is an example of an open standard.
Other changes have occurred since the OSI model was originally conceived:
The data link layer has been defined as having two sublayers: media access control (MAC) and logical link control (LLC). The MAC sublayer
determines who is allowed to access the media at any one time. The LLC multiplexes protocols running on top of the data link layer and can
provide flow control, acknowledgement, and error notification.
The network layer has been defined as having three sublayers (to support internetworking):
subnetwork independent convergence
subnetwork dependent convergence
subnetwork dependent access
Network management is now considered part of the reference model environment. This model has five functional areas:
fault (to recognize, isolate, correct, and log faults that occur in the network)
configuration (to gather, set, and track configurations of the devices)
accounting (to gather usage statistics of users)
performance (to improve and determine the efficiency of the network)
security (to control access to assets)
Changes to the model are likely to continue, but no radical changes are anticipated. Although the forces that brought the OSI model into existence
appear to have been well-intentioned and well-supported, few pure OSI implementations seem to exist. The networking architecture is the TCP/IP
suite. Mixed OSI/TCP/IP networks also exist, as it is fairly easy to replace ISO layers 5-7 with TCP/IP application-layer entities.
On a given computer (host), several networks may be attached and several protocol stacks may actually be in parallel use. For example, your e-mail
installation may be running SMTP (simple mail transfer protocol) from the TCP/IP suite, but be attached to both a TCP/IP network and an OSI network.
In this case, the application would fan-out, selecting the appropriate transport protocol with which to communicate to a specific computer’s e-mail
connection. Were this an OSI-only situation, the session layer would be responsible for properly managing the required mail connection. If, on the
other hand, you had two e-mail applications (e.g., X.400 and SMTP) running in parallel over a single network connection, there might be a fan-in to the
single transport layer entity.
Try this Module 4. Knowledge Check 1 – Please go to My Tools -> Self Assessments -> to
complete this self assessment.
E. The TCP/IP Suite
The TCP/IP model, the result of many years of evolution and experience, is remarkably parallel to the OSI model. The primary difference is that the top
three layers of the OSI model are represented in the single application layer in the TCP/IP model. Much of the same functionality is present in both.
Another major difference is that most TCP/IP applications are defined for a single data representation, whereas the presentation layer in the OSI model
makes it possible for applications to operate in a fashion independent of the data representation.
Applications are generally connection-oriented rather than connectionless, which means that the first thing your application agent program needs to do
to send Internet mail, transfer a file, or emulate terminal services (or any of the other application services) is to establish a connection through which
data will pass to a remote host. The destination host typically has listener applications (frequently called daemons) running for all of the services it is
willing to provide to requesting hosts. On the Internet, these listeners are most often assigned to and monitor specific virtual port addresses known
as well-known ports. Thus, if a given host does not support the application for which a well-known port has been designed, no listener monitors that
port number, and requests destined for the associated port end up being ignored (alternatively, a listener may be monitoring and send back a “reset”
packet indicating that the request was heard but is being rejected). Additionally, listener applications can be replicated to a different port number
(normally outside the “well-known” range), and that application can be made available to clients who know the uncustomary port assignment.
Commonly used well-known ports and associated protocols include Telnet on port 23, SMTP (e-mail) on port 25, SSH (secure shell) on port 22, HTTP on
port 80, and FTP on ports 20 (data) and 21 (control).
When a request is received using the appropriate protocol with the proper virtual port address, the listener sets up an application of the proper type
and assigns an unused virtual port address outside the well-known range that will be used by the session. It then sends a reply to the requesting host
(to the virtual port address from which the request was received) including the virtual port address assigned to the application it just set up. In special
circumstances, the listener application can handle all requests itself. The web is an example of such stateless operation. For example, with SMTP on
port 25, the e-mail system being used (like Hotmail) has a setting for an SMTP server. When an e-mail is sent, a connection is created to that SMTP
server over port 25, the message is transferred, and the connection is closed. After that, the SMTP server looks up the destination host for the e-mail
Please click on the OSI Overview button to begin.
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(the part of the e-mail address after the @ sign) and connects to that SMTP server, also over port 25. The mail is transferred to this new server and
delivered to the appropriate user.
When both sides of client and server applications establish a port connection, the communication has been established in a socket connection. A socket
connection is established when both Internet Protocols (IP) and their port connections are connected to communicate between those two
communication nodes. Every communication connection starts in this fashion to exchange any communication data. The receiving node always has to
have an open and listening port to accept a connection request from the sending node. While both of these nodes establish a TCP/IP connection, a
three-way handshake (SYN, SYN-ACK, ACK) takes place to properly ensure that it is a connection-oriented establishment prior to transmitting any
data. In a three-way handshake, the originator of the connection sends a packet that flags the TCP as SYN (for synchronize) set. This is called a SYN
packet. The server will reply with a SYN/ACK packet, and the connection originator replies with an ACK (for acknowledge) packet. For example, this
handshake process is similar to our own conversations with another person:
Me: Hello? Are you there? (SYN)
Other person: Yes, I’m here. (SYN/ACK)
Me: Good! I need to talk to you about (ACK)
Figure 4.4
The Handshake Process
When transmitting data in this fashion, it ensures data integrity and delivery guarantee, since TCP will retransmit until the receiver acknowledges the
reception of the packet. You can see that there is a fair amount of preparation prior to transmitting any real data in order to establish a guaranteed
delivery. The data guarantee is the reason why the Internet is using the TCP/IP connection for most of its routing protocols, and why the growth of the
Internet has been exponential.
Note that the protocols used at the lower layers may be either connection-oriented or connectionless. Certainly, the message to the listener application,
because of the simplicity of the job the listener performs and the minimal amount of data required to perform it, does not need to have a pre-
established connection. TCP is actually the connection-oriented protocol at the transport or host-to-host layer. The connectionless protocol at the same
layer is known as UDP (User Datagram Protocol).
TCP/IP has an architectural difference from the OSI model that should be mentioned: Layers can be bypassed. The OSI model has a strict rule that a
layer (or sublayer) must always be present, even if all the service requests result in duplication of the request to the next lower layeressentially a null
layer. TCP/IP’s architecture permits bypassing unnecessary layers and delivering service requests directly to the module that can act on them.
Figure 4.5
OSI and TCP/IP Protocol Stacks
Figure 4.5 depicts the correlation between the OSI and TCP/IP models and how they correspond to each other when discussing each layer of protocols.
Each layer protocol data unit also explains what kind of data is being transmitted in each layer. For example, the first physical layer deals
with bits and bytes of raw data on the physical media, such as Ethernet or fiber optic. The data link layer forwards frames of information to
other switching topologies. Switching devices run in this data link layer, which is a very popular layer in the local and wide area networks. One of the
reasons that layer is popular in the switching technology is that layer 2 technology is very efficient in forwarding frames of information to other
switching technologies. Layer 2 technology is proficient in moving data from one network node to the next, since we are dealing with layer 2 rather
than layer 3 routing. Moving messages up and down protocol stacks can take process
