Content Delivery Networks (CDN): Advantages, Disadvantages, and Technical Details

This document provides a comprehensive guide on Content Delivery Networks (CDN). It covers the advantages, disadvantages, and technical details of CDN, including how it improves user experience, reduces bandwidth requirements, and impacts SEO rankings.

Running head: SYSTEM ADMINISTRATION
System Administration
Name of the Student
Name of the University
Authors note

1SYSTEM ADMINISTRATION
Task 1
ifconfig:
use: Used in order to configure and maintain the system network interfaces that are used to
connect to network.
Syntax: ifconfig –a
ifconfig enp0s3 up-.
ifconfig enp0s3 down
ifconfig enp0s3-
ifconfig enp0s3 mtu 1000
screenshot:

2SYSTEM ADMINISTRATION
traceroute:
Used to track the loss of data packets in the network.
traceroute facebook.com –q 10
traceroute facebook.com –w .5
Answer 2
echo "Choose one of the Following"
echo "1. Show my StudentID and Name"
echo "2.Find the Divisors of an Integer"
echo "3. Exit"
read n

3SYSTEM ADMINISTRATION
case $n in
1)echo " StudentID:MIT173864 and Name: Syed Fayyez aAi";;
2)echo "Enter a number"
read l
n=$l
for (( i=2; i<=$l; i++ ));do
while [ $((n%$i)) == 0 ];do
echo $i
n=$((n/$i))
done
done;;
3)exit 1 ;;
esac
Task 2
Introduction
With the exponential growth of internet and new modes of available Web services, this
triggered the generation of huge amount of Web content as well as Internet traffic. In order to
accommodate larger amount of content and delivery of those contents the CDN or the Content
Delivery Networks (CDN) developed [5]. The CDN is very helpful in overcoming limitations of Internet
in order to deliver the contents. Primary concept behind this technology is to deliver the user
requested contents at the edge of internet network in order to improve user’s perceived
performance as well as reducing the costs for the delivery of the contents.
Background information/history of development
The CDN can be simply defined as the distributed network of cloud file storage and servers
that are responsible for replicating services or files such as document files, videos on an enormous
number of backup systems that placed at multiple locations which are available and distributed
throughout the globe to serve better to user.
Initially the CDN is developed and designed in order to distribute frequently requested
contents on the internet from the prevalent web servers. Initially, the most of this resources or files
were image files or documents [4]. The execution advantages of a very appropriated design hold not

4SYSTEM ADMINISTRATION
just for cacheable substance that can be conveyed legitimately by the CDN yet additionally for un-
cacheable substance that requires a full round trek back to the starting point. A profoundly
conveyed stage is likewise basic for the increasing speed of dynamic substance. CDNs can speed
server-to-server correspondences inside their stages utilizing different course and transport
convention improvements [6]. At the present time, CDN supports and is used in the delivery of
dynamic content. This even includes different type of media streaming. The following diagram
shows the usual architecture of a content delivery network [9]. Even though, it is important to state
that, depending upon the type of content provided, the specifications may be changed.
Technical details and features
In any model, all CDN architectures principally involve a origin server, a substantial number
of surrogate servers to be specific they are represented as Point of Presence (POP) and lastly a
request redirecting mechanism. Details of all these components are provided below;
Origin server: This server is responsible for storing all the contents or potentially the
metadata about all the content that needs to be delivered. In order to accomplish superior
performance of the entire CDN, the content in the origin servers are pushed to POP servers [2]. As
this surrogate server are situated at various geological areas over the globe thus this POP server are
capable of delivering the user requested resources or content much faster.
POP servers: This server are present in in an expansive number at various territories in a
CDN. The principle capacity of pop server is to offer the content dependent on client demand. At the
point when the content is not accessible locally, the pop server should pull it from the origin server
and stores it [8]. So that for the following plausible prerequisite; as it may be conceivable that the
equivalent/different user(s) in the area will require the content.
Prefetching is another significant functionality that is used by the POP server where it gets
the content that users inside a certain geographical location might be interested in from the origin
server accordingly decreasing the opportunity of congestion in traffic particularly amid the high
demand for the customer.
Redirecting mechanism: Another important component in the CDN is the request
redirecting mechanism. This mechanism dynamically redirect users requests to most optimal POP
servers depending on multiple parameters [5]. This parameter includes server load, network
congestion, latency, proximity, user accessible network congestion.

5SYSTEM ADMINISTRATION
Target platform
For the CDN, the main target platform is internet or Web. In order to improve user
experience as well as make the content reachable with the efficient network resource utilization the
CDN uses its POP servers and redirecting mechanism[1]. Mostly the media companies, e-commerce
organizations use CDN operators in order to deliver content to the targeted audience in dispersed
geo locations.
Advantages and Disadvantages
Advantages
Following are the most important advantages of CDN;
 Static content from the internet is served from the nearest POP server that leads to
the reduced bandwidth requirements.
 CDN copies and stores the content in multiple geographically dispersed servers. This
storage of the content while dividing the load among those servers. In this way a
website or resource is made highly available to the visitors with faster speeds.
 The CDN service is also helpful for the websites to improve their SEO ranking and
lifts Google page rankings in the indexes[3]. The reason behind this can be stated as
poor and slow loading sites faces challenges in order to rank good in google page
rakings.
 CDN is also very useful for Websites that serves and contains larger high quality
Images, videos to improve their loading speeds.
Disadvantages
 Despite the above mentioned advantage there are certain downsides of CDN which
are listed below;
 In order to set up a Content delivery networks requires extra investment for the
website owners.
 This CDN also adds up complexity to deployment procedures of the websites or web
services.
 Users may be in certain regions in which there are network filters which blocks some
of the Content delivery networks(CDN) and which may prevent content from being
loaded on the websites [8].
 It may happen that the Geo-location of the POP servers are not close to the target
audience. Even it may happen that it might lead to losing any beneficial speed
upgrade.

6SYSTEM ADMINISTRATION
Conclusion
Inside the present dynamic landscape of internet and its usage, it is very important for the
service or the content providers to understand and meet the requirements of the users through the
use of CDN technology. If we consider any of the video distribution services such as YouTube, they
are responsible for distributing the video content to the geographically scattered subscribers.
Depending on their location the video quality can differ because of the long delivery path to the
subscriber. In this scenario the negative sensitivity of the users or the subscribers due to the bad
video quality can adversely impact on subscriptions and consequently to the revenue of the
business.

7SYSTEM ADMINISTRATION
References
[1] K. Poularakis, G. Iosifidis, A. Argyriou, I. Koutsopoulos, and L. Tassiulas, “Caching and
operator cooperation policies for layered video content delivery,” in Proceedings - IEEE INFOCOM,
2016.
[2] H. Nam, D. Calin, and H. Schulzrinne, “Intelligent content delivery over wireless via
SDN,” in 2015 IEEE Wireless Communications and Networking Conference, WCNC 2015, 2015.
[3] A. Hameed et al., “A survey and taxonomy on energy efficient resource allocation
techniques for cloud computing systems,” Computing, 2016.
[4] M. Z. Shafiq, A. R. Khakpour, and A. X. Liu, “Characterizing caching workload of a
large commercial Content Delivery Network,” in Proceedings - IEEE INFOCOM, 2016.
[5] J. O. Fajardo, I. Taboada, and F. Liberal, “Improving content delivery efficiency
through multi-layer mobile edge adaptation,” IEEE Netw., 2015.
[6] M. Gupta and D. Kumar, “State-of-the-art of Content Delivery Network,” Int. J.
Comput. Sci. Inf. Technol., 2014.
[7] D. Tuncer et al., “Scalable Cache Management for ISP-Operated Content Delivery
Services,” IEEE J. Sel. Areas Commun., 2016.
[8] Z. Li, Q. Wu, K. Salamatian, and G. Xie, “Video delivery performance of a large-scale
vod system and the implications on content delivery,” IEEE Trans. Multimed., 2015.
[9] C. Yang, Y. Yao, Z. Chen, and B. Xia, “Analysis on Cache-Enabled Wireless
Heterogeneous Networks,” IEEE Trans. Wirel. Commun., 2016.
[10] J. Sung, M. Kim, K. Lim, and J. K. K. Rhee, “Efficient Cache Placement Strategy in Two-
Tier Wireless Content Delivery Network,” IEEE Trans. Multimed., 2016.
[11] G. Ma, Z. Wang, M. Zhang, J. Ye, M. Chen, and W. Zhu, “Understanding Performance
of Edge Content Caching for Mobile Video Streaming,” IEEE J. Sel. Areas Commun., 2017.
[12] J. Sahoo, M. A. Salahuddin, R. Glitho, H. Elbiaze, and W. Ajib, “A Survey on Replica
Server Placement Algorithms for Content Delivery Networks,” IEEE Communications Surveys and
Tutorials. 2017.
[13] D. Kim, J. H. Kim, C. Moon, J. Choi, and I. Yeom, “Efficient content delivery in mobile
ad-hoc networks using CCN,” Ad Hoc Networks, 2016.