Supporting Quality of Service (QoS) in Today's Heterogeneous Network

The assignment content discusses the four pillars of network design, namely Quality of Service (QoS), Security, Manageability, and Scalability, which are essential for designing a heterogeneous network that supports various applications and services. The four pillars are described as follows: QoS includes packet classification, isolation, high resource utilization, and call admission to ensure quality delivery of traffic flows in the network. The existing network infrastructure at all campuses in the university is also briefly described, highlighting the hardware specifications used at metro, regional, main, and backup sites.

Network Redesign for FNU
Overview
Business Domain:
The network redesigning is required at The First National University (FNU). FNU is a higher
educational organization for long distance learning. This is the first educational organization
providing online courses in the country. The university runs online training and courses; it requires a
network infrastructure of very high performance to provide Quality of Services to the end users. The
university covers 5 regional campuses and 10 metropolitan campuses and a main campus to run
such a huge educational institute. University offers undergraduates programs and postgraduate
programs through distance learning. Moreover it provides Vocational and Educational Training (VET)
as well as short programs for professionals to increase their skills. FNU teaches 45,000 students at
both undergraduate and postgraduate level for various programs on-campus whereas 15,000
students are studying off-campus for distance education at FNU. To ensure services to be delivered
at all the ends, FNU’s network is designed to divide into 3 facility centers. Firstly, Headquarters,
where main campus is located. Second, Operation i.e. Data Centre which is located 50 km away from
headquarters. At the Operations center, the technical staff is appointed for managing and
performing IT related tasks required for proper functioning of the network. The third division is the
Backup Facility. Backup facility is located 1000 km away from the main campus. This is because
backup facility is needed only when operation facility breaks down.
Network Issues:
1. As discussed above, due to heavy number of users on the network, it may result in network slow
down. The online submission is the key facility provided by FNU for ease of submission and
evaluation for the students as well as staff members. Due to online submission for both on-campus
and off-campus students, it has been observed quite a few times that the network problems
appear which makes the late submission for most of the students which in turn results in the bad
grades.
2. FNU has no Bring your own device (BYOD) and Work at home (WAT) policies embodied in the
network which is highly needed by the students and staff to make it possible to work from their
own devices. For this purpose, the secure wireless network should be implemented which
supports BYOD and WAT.
Immediate actions to take in regards of the identified issues:
1. Scalability for 50% increased enrollment in next three years.
2. Improvements with issues in online assignment submissions.
3. Implementation of bring your own device policy by adhering wireless network in the campus.
This enables the students to work on their own laptops, tablets, notebooks and smartphones.
4. With WAT it will allow users (students and staff members) to access network facilities from

their homes.
5. Security measures must be taken to safeguard data from the hackers.
6. Providing Quality of Services to the network users both at on-campus and off-campus.
Identify Organisation’s Needs and Constraints
Business Goals
FNU is divided into regional and metropolitan campuses that are all similar in size of infrastructure,
staff members and technology. These campuses are all well built with network and required
technologies which serves at its best to the students studying in that campus. With academic
teaching and learning activities both on-campus and off-campus, FNU also has 12 external partners
some of them are:
Hospital: FNU deals with providing training to students for hospitals. On the other fair side, FNU
helps hospitals to get their best interns at the optimum search. The hospitals get benefited by
appointing best candidates at their hospitals with limited searching. The university offers all the
medical related courses which help hospitals to get the best suited candidate.
Research Center: FNU may help students by providing current research practices due to its
partnerships with research centers. It benefits students for future reference. On the contrary, the
research centers uses data and statistics from the university to research further about a particular
field of interest. FNU ties up with such research centers to allow them to perform researches in
some areas.
Vendor Support and Technology are other fields FNU have partnerships with which one or the
other way benefits the students learning process. Also, the FNU offers campus interviews for the
students to get placed in various companies which in turn benefit the companies for selecting best
candidates on the basis of their grades.
As per the requirements discussed above for FNU, it becomes very important to identify the
organizations goals to provide best services to the users of the network, be it students, teaching staff or
technical staff. The business goals are as elaborated below:
1. The university is currently having 45,000 students at both undergraduate and postgraduate level
for various programs on-campus whereas 15,000 students are studying off-campus for distance
education. Future goal of university is to expect new enrollments of 50% rise in upcoming three
years. From the business point of view, the FNU is preparing to add new students both on-
campus and off-campus. FNU presumes to increase the students at the largest possible rate by
providing learning in new and currently trending fields.
2. The FNU provides day learning courses for on-campus students. These activities can also be
extended to short training programs to attract more students and get more enrollments on-
campus. Some short training courses should also be undertaken with certification that will
attract more students seeking for on-campus education for limited time period.
3. The off-campus online courses provided by the university are limited to some extents. To
increase the enrollments, it is required to introduce new training courses. With new courses

added in online training or long distance learning it is possible to attract off-campus students for
distance education.
4. As far as partnership related expansion is concerned, the FNU administrative and managerial
staff must communicate with more hospitals, companies and research centers. These partners
extension result in attracting more students. Also it may result in recognition from various other
universities.
5. To provide large number of courses for huge number of students, FNU is aiming to provide the
best network for the users. The current goal is to redesign the university network to provide end
to end services without any interruption. Many students using network all the time must have a
heavy load at every moment. FNU aims to use better network policies for the entire network.
6. Foremost goal of FNU is to increase students and this increase in students will result in heavy
loads at metropolitan campuses. This will result in increased number of regional campuses for
distributing students.
7. University also aims at providing BYOD and WAT policies in the network for more usability in the
network.
Needs of improvements in FNU Network:
1. Since several numbers of students and staff members uses the network, FNU network must be
very good at providing best performance. Right from internet surfing to downloading files,
sending emails and providing high end network performance is the high need of the network.
2. The business goal of FNU is to increase number of students by 50% in the next three years;
hence it requires a network design which is highly scalable in nature. New PCs at campus must
be added up in the network without much overhead is the basic need of the network since more
number of students is expected to be increasing in upcoming years.
3. The university provides off-campus distance learning and hence must be available at any time
for its distance learners. Moreover, it requires the student’s on-campus to submit their
assignments online; hence availability of network is very important at that part as well.
4. FNU must also provide Bring Your Own Device and Work AT Home policies in the network for
more usability in the network. These policies are highly needed at the university since it is
affecting the usability of the network. Once more and more personal devices can be connected
to the network, it will affect in overall students learning process.
5. FNU needs to implement a secure wireless network which safeguards student’s login
credentials, files, and other important assets. Moreover, it may restrict the intruder getting into
the network by facilitating strict security measures. Authentication will also need once BYOD
and WAT policies discussed above are implemented in the network to filter illegal activities. The
other security measures should also be taken to protect important files in the server.
Constraints in FNU network
1. Foremost limitation of FNU network is that it does not support bring-your-own-device (BYOD)
which makes it difficult for students to migrate their work from university PCs to laptops and
vice versa. With this limitation students cannot work from their own laptops, notebooks or
tablets.

2. The network does not support work at home (WAT) policy which does not allow users to access
university network from their personal spaces. WAT must be provided by the university which
will help staff members to carry their pending work out from their homes.
3. Another noticeable limitation is that it sometimes fails to upload assignments due to poor
performance which leads in late submission of homework. This eventually results in poor grades
of the students. The load at the deadline of the submission is observed to be very heavy in the
network which results in slow down of the network and hence students are unable to upload
their assignments on time.
4. The main campus of the university holds large number of users including students and staff.
Other campuses like regional and metropolitan campuses are in similar sizes and technology
usage. All those campuses use old complex technologies which are out-dated and results in
poor performance of the network.
Some technical issues are also noticed in the network which is needed to be noticed and fixed as early as
possible. The technical goals related to the university network as discussed below:
Technical Goals:
1. Scalability
Scalability can be best defined as the ability of the network to ensure no degradation in overall
network performance even if the network size in increased. Scalability is one of the most
important features a sound network can attain. It is the property of the network to add devices
to its existing cluster in such a manner that new added devices do not collectively form a load
that exceeds the cluster’s collective load to offer adequate performance. Scalability once
attained on the network, provides good quality of services in the network since it eventually
relates to the network performance.
The redesigned FNU network must have this feature so that it can be scaled to support
extended usage of services including multimedia applications. This feature is important in FNU
so as to include online teaching in its training part. FNU must provide scalable network for
further enrollments of the new students both on-campus and off-campus. This features must be
employed everywhere at all the campuses. There are several techniques to attain scalability
these are, Network Load Balancing (NLB), scaling up and scaling out. Network load balancing is
the trustworthy technique that allows the network to assess the load on the network and
balance it to provide better network performance. FNU network needs high scalability for its
goal to enroll 50% of the current strength in next three years.
2. Availability (half a page)
The organizations with multiple data centers, network availability are a vital concern. To
perform operations daily such as downloading files from server at FNU requires high need
of network availability because users performing daily operations in the network need the
network to be available all the time. Availability is serious when it comes to disaster

planning and recovery. FNU aims at providing a network that is available approximately
99.9 percent of the time and offers an MTBF (mean-time-between-failure) of 6000 hours
and an MTTR (mean-time-to- repair) of less than 90 minutes. Network availability with
these values can never fail even at the students’ submission deadlines. As per students
complaints about network slow down at the time of submission, the network with such
availability metrics can fulfill their request of network availability. A key concern FNU’s
students and staff is concerned about is availability of network at their personal spaces so
that they can work from home as well. Implementing WAT in the FNU network is in
demand from students and staff of the network.
3. Network performance
The overall network statistics assessment to define and analyze if the network is capable
of serving quality of services is termed as network performance. It quantitatively and
qualitatively assesses the performance of the computer network which tells the network
administrator to observe, analyze and improve the services provided by the network.
Network performance is measured as:
Bandwidth: metrics for data transfer rate.
Throughput: the maximum amount of data transferred at one time in the network.
Delay and latency: The extra time taken by the: data than the stipulated one.
Jitter: the difference in data flow within the network due to congestion.
Data loss: Data drop before its delivery to the recipient.
The above mentioned parameters define the overall network performance of the
network. Any of the parameter is failing to achieve its quality in the network leads to
complete drop of network performance. FNU wants to provide a wireless network that is
privately secured for students, staff members and visitors as well. With many users on
the network, FNU needs to be redesigned to fully satisfy the network performance.
FNU’s network must also have a response time less than a second for interactive
applications. The network administrators must increase the bandwidth of the Internet
connection to support new applications in the network.
4. Security (half a page)
Security is a key concern in any network even if it is as small as ten computers. FNU’s big
network is under the threat of security breaches. With wireless network, security comes into
picture since wireless network themselves are less secure. Some security measures are needed
to be employed in the network to make it secure. Network security is the act of safeguarding
network data as well as network devices from intruders and malware attacks. With large
number of users and several numbers of devices in the network, security is a key feature to
work on.
FNU’s network must be redesigned to protect the end to end device connections. Moreover, it is
needed to safeguard network from hackers stealing authentication and authorization rights in
the network. To achieve high level of security, network layer of the protocol stack implements
various algorithms, policies and controls which benefits by providing access to the authorized

users in the network while prohibiting false users to enter into the network. Security not only
protects your personal data and login credentials in the network but ultimately protects your
reputation. FNU with so many users at a time needs a concrete security measures so that no
reputation will be threatened.
5. Manageability
A network is said to be manageable if it allows most of its tasks to be automated. The FNU
network is very huge with different and diverse tasks and services within the network.
Manageability is required at the IP support end where there are many tasks to work on
especially regarding network management. If more of the tasks are automated, the network
itself reduces most of the burden from IP support staff. These tasks include:
1. Network Configuration
2. Data Backups
3. Load Balancing
4. Network Management
5. Network Monitoring
6. Troubleshooting
7. Updates
The tasks once performed by itself, network is said to be manageable. FNU’s network should
also be redesigned to perform several tasks by its own.
6. Usability
Usability of the network or an application is defined as the ease of access of such
products that helps user to use it by using all its functions with utmost ease. The network
usability is how effortlessly and easily a network user can use the network without having
issues like operational issues or connection issues. The FNU network is very complex and
supports various users’ at a time and hence requires the great degree of usability. The
network and its applications should be so very easy that the students and staff members
must handle it very easily. The applications in the network includes university website
that manages students, their submissions, results display, etc. Network usability plays an
important part when the network or its applications are difficult to use.
With usability, network administrators can assess the level of difficulty and redesign its
applications for ease of access to its users. FNU’s network must be easy to operate for
the students and staff so as to make it effective in use for them. Students in the network
are very much new to this kind of environment hence usability must be achieved by the
network for making it easier to use it. Usability in the network can be accomplished by
first analyzing which areas are difficult in use and hence redesigning it may help in
attaining usability.
7. Adaptability

The network is said to be adaptable of small changes done in the network that does not affect
the overall performance. The FNU’s network is currently using wired services but now FNU’s
administrators are planning to provide wireless services provisions to students and staff
members. The new network must be designed with wireless provisions and hence it must be
adaptable to new changes in the network. The network adaptability is the ability of the network
to respond positively to the change and hence fit into the new circumstances. Repair the IP
addressing scheme of the old network since the network is planned to migrate to the wireless
technology.
FNU network is requires all its users to use bring your own device policy in which personal
devices of the students can also be connected into the network without any difficulty or
connection issues. Availability of network will allow its students to connect their personal
devices with utmost ease. Moreover, FNU is planning to implement the WAT policy in which the
university network will be available all over the globe so as to help its staff to work at home. In
order to make these two policies implemented in the network, FNU needs to implement a
network with high availability.
8. Affordability
With implementation of security, usability, availability and other technical goals in the network, it
becomes very difficult for the network administrators to keep the network affordable. With the security
concerns, the new devices and software needs to be employed in the network. These devices are
somewhat costly and may vary in price when you need it again in next few years. To make a network
available and usable, it also requires a good sum of amount. Moreover, to make it manageable is a hectic
task since it is available, usable and secure. Managing a huge network is also not easy to cope up with.
FNU’s network must be affordable in cost since its new requirements are very high. Some important
concerns affecting affordability of the network are as given below:
1. Adding new wireless devices in the network may lead to extra investments.
2. With the employment of new security features, the network needs to add new supporting
technologies and network security software to accomplish the new requirements related to security
concerns.
3. Wireless technology is more prone to security threats and hence new QoS support is needed to be
employed in the network.
The QoS support required in the network:
The network in its initial years was simpler than today’s network. IP telephony, Audio video streaming
are some more complicated and crucial part of today’s network traffic and the time effective delivery of
service without data loss has become more important today. Hence four above mentioned pillars are
highly needed to support Quality of service in today’s heterogeneous network. The merits of all four
pillars are described as below:
1. Packet Classification: It ensures classification of packets at router and differentiates them to the
different classes of traffic. Packet classification is extremely important task of the network. Switches
in Ethernet uses packet classification to select the packet paths instead of de-multiplexing. It helps
switches to classify packets and enroute them very efficiently rather than any other technique.
Packet classification ensures fast delivery of packet by saving overhead time. Also router in the

network which sends packets over Multiprotocol Label Switching tunnels makes a good use of
classification to save time.
2. Isolation: To ensure Quality of Service in the heterogeneous network, all the resources must be
dedicated to the desired operation in the network. For example, the bandwidth, links and buffers
must be isolated for one transfer operation and same resources should not be allocated to another
operation in the network.
3. High Resource Utilization: Another pillar for supporting Quality of Service in network is allocation of
resources in such a way that it does not affect negatively by another misbehaving flow. This ensures
degree of isolation between flows of packet in such a way that it doesn’t affect the other traffic flow.
This allows using resources of the network efficiently and in optimum manner. Consider at an
instance, if non-sharable fixed bandwidth is allocated for the flow may get wasted if not in use
currently. Hence the merit of this pillar may sometimes prove to be non-beneficial.
4. Call admission: When isolation of resources sometimes causes unavailability of sufficient resources
for another task in the network, the concept of call admission comes into a picture and proves to be
very beneficial. In call admission, the flows declare their requirements of resources to achieve
Quality of Service. On the basis of their requirements, the flow is then admitted to the network if it
can satisfy the requirements declared. Otherwise, the flow id blocked till the sufficient resources are
free. Call admission controls and regulates the traffic flow in the network to ensure that the current
flow is attaining quality delivery without compromising the QoS of the existing flows. Call admission
process is highly beneficial where the traffic contains audio/video data. This process ensures quality
delivery of audio and video in wireless communication and IP telephony. It first checks the network
environment and then decides if this traffic flow will get delivered without sacrificing QoS levels. On
this basis, the traffic is either blocked or allowed to pass through the network.
Existing Network
This section briefly describes the current infrastructure implemented at all the campuses in the
university. As stated before, all the regional and metropolitan campuses are using the same size of
network, devices and staff. Following are the hardware specifications currently used at all university
sites.
Hardware at Metro and Regional campuses
 Computer Labs: 10, 24 PCs each with Windows OS and a printer
 Staff PCs: Windows 7 (dual monitors), headsets and webcams.
 Networked Printers: 4 in each faculty.
 Local Network Storage: 1
 Switched Ethernet: 100Base-Tx
Hardware at main campus
 Computer Labs: 50, 24 PCs each with Windows 10 OS and a printer
 Staff PCs: Windows 10 (dual monitors), headsets, webcams and VoIP video phones.
 Networked Printers: 20 capable of scanning and photocopying.
 Local Network Storage: 1
 Switched Ethernet: 100Base-Tx

Hardware at Operations site
 Servers: Windows and Linux Servers capable of operations like mail, DNS, DHCP, web,
authentication, domain controlling, SAN, database, load balancing, blackboard and video
streaming. The servers at operations site also support FNU’s online learning management and
students’ information management. It also handles ERP services.
 Staff PCs: Windows 8 OS.
Hardware at Backup site
The backup site comes into picture immediately if the operations site fails. It has the same
infrastructure as a backup site and deals with backing up all the data from operations site
periodically. The backup site is far away from the main campus and requires same hardware as
operations site. Once the failure in the network or break down in detected, the backup site loads all
the data from its servers to the operations site with few minutes to revive the network. The services
provided by the operations site are all mirrored by backup site. The backup site is barely used site
but it is of great importance if operations site fails. It helps in recovering the network data.