Network and Security Report: Protocols, Security, and Multimedia

This report provides a comprehensive analysis of network and security concepts. It begins by examining application protocols such as HTTP and HTML, highlighting their advantages and the importance of security practices like cookie management. The report then delves into application and security protocols, discussing APIs, Berkeley sockets, and the role of license managers in network access. It explores network architectures, comparing non-NAT and NAT-based DMZ configurations and emphasizing the security benefits of dual-firewall systems. The report also addresses security threats like man-in-the-middle and replay attacks, contrasting scenarios with and without tagging to illustrate the importance of encryption. Finally, it touches upon multimedia networks, covering audio, video, and mixed data formats, providing a holistic view of network security and data communication principles.

1. Application protocols
(a) The HTTP is abbreviated as Hypertext transfer protocol. The HTTP is a application protocol in the distributed
system, collaborative system and hypermedia systems. The HTTP is a kind of foundation in the data communication
on the internet. This is a kind of the structured text. This structured text will use the logical links known as
hyperlinks. These links connected in nodes which have data. HTTP can be called as a protocol for the transferring
data. When user request for data the HTTP carries a request message to server and get the data. The first version of
HTTP was released in the year 1991 which is called as 0.9. The next version is 1.0 released in the year 1996. The 1.1
version was released in the year 1997. The 2.0 version was released in the year 2015. The HTML is abbreviated as
Hypertext markup language. The HTML is a standard of markup language. The HTML is used for creating the pages
and applications in web with CCS, cascading style sheets. They also use JAVA script for World Wide Web. This will
generally gives the structure of web page [1].
(b) The HTTP 1.1 has many advantages. It has Extensibility which makes compatibility with many other versions and
softwares. The Caching will make device faster. It has best Bandwidth optimization. The Network kind of connection
management is very good. It has best Message transmission facility. The Internet address related conservation is
also good [4]. The Error notification is also better. The Security high is with best integrity and the authentication.
(c) The cookies are never a good idea. If someone is sending them try to warn them not to do so. You also never try
to send them back. If they are sending back again and again try to block them or take serious issue with cyber
officials.
(d) ASCII is abbreviated as American standard code for information interchange. This is a kind of information
exchange system for the electronics and communications. The ASCII is generally used in computers and the
communication systems. This is one of the best encoding system [3 ]. There are many advantages. ASCII will allow all
the computers to use the similar input data and the input characters. This is one of the standard code will allow to
create many file possible. The general length of ASCII is 7 bit but the 7 bits will allow to store 128 binary patterns.
And so on with the increase in character length and the bit length.
2. Application and security protocols
(a)
API is abbreviated as application program interface. The API are set of some procedures
Like protocol and some tools in the process of building software’s and its applications. We know the graphic user
interfaces will help the users in many ways, similarly the API will help the programmers for developing new
software. This is one way of integration of technology with the business models and other systems. This is one of the
best business ecosystems. The APIs are like blocks and one must integrate the blocks. They all must be joined for the
forming a good system. The API can be applied to any systems like web technology, data systems, hardware of the

computers and many more. There is a concept known as the API calls. In this a call made by the user to server is
known as API call or the request.
(b)
In the given problem the Berkeley socket is discussed. Here the socket is a API to the internet with the Unix domain
socket are also used in IPC. The IPC is abbreviated as inter process communication. The IPC is used as linkable
modules. The socket is defined as an abstract place or the endpoint in the network or the communication path. The
Berkeley socket is a API which tells about the common interface to the input and output for the data. The next type
of Berkeley socket is the POSIX sockets. This is also termed as BSD socket. There are few things which are done by
the POSIX. They are the conversion of the text address into a packed address. The next one is to convert from the
packed address into the text address. The next kind is the forward lookup into a host name or service. The final one
is the reverse lookup to host name or the service.
(c)
Let us discuss some of the causes for the above question. In the data communication or the access the team of the
network security needs some kind of information for providing the access to the licensing the components.
Some of the best examples for this kind of solution are the explained in the IBM model. In this they need some
license key for the server access. This license is known as the floating license key. Few of it are imaged- this is a
license manager demon. The next kind is the vendor demon. They are denoted with key names like immortal, the
next one is the rational and the final one is the telelogic.
Here the manager demon and the vendor demon both of the demons use the TCP to communicate, the application
layer protocol take control of the FLEXnet publisher which is proprietary over the TCP/IP.
(d)
When the license manger is involved with sending a hardware key for the client, then there are three cases, first one
is the accepted, next rejected and the final one is the expired. If the user is asking the same question after and after
for the long time then they must check the process. There is a possible attacks in the communication. There are two
cases of attacks, first one is the middle man attack and the next one is the end user attack. These can happen
because if the third person is involving in your communication path. The best way to avoid these kind of problems
are by establishing the secure communication. Some of them are the encoding the key or data, the next one is the
acknowledgement based method.
3.
(a) The below system will not use the NAT, this is a non NAT model. This contains the remote clients, which is an
end user. The remote client is connected to the internet. The internet access is done with the help of routers. The

routers are protected by the firewall [2]. Then they are connected to the web servers of different models like the
data base servers, link systems.
The DMZ is denoted with the demilitarized zone, the DMZ is also known as the perimeter of the network. The DMZ
is a type of the physical or the logical type sub network which contains the external threats facing by the firm. They
also show the untrusted networks before the organization is making data transaction between the systems. Most of
the issues will help in the presence of the internet. The main purpose of the DMZ is that it will add an extra security
for the organization in the local area network (LAN).The external servers or node can access the data only through
the DMZ. This is present in the network firewall. The DMZ is present between the node and the private network. In
below case, the DMZ is present between the LAN and the external internet WAN [5].
The above picture shows the DMZ with a single firewall system. The single firewalls will have at least 3 network
interfaces. This will create a new architecture with DMZ. The first interface is with the two internal points. The
second one is with the internal server and the firewall. The final interface is between the external node and the
DMZ. The main problem with the single DMZ is if the firewall fails the purpose is spoiled [7]. Hence it is necessary to
add an extra DMZ. To know the zone it has to represent with as many colors as possible for easy representation.
Red, blue and other colors were used differentiating.

The next one is the DMZ with the two firewall system.
The above single firewall system disadvantages are corrected with this system. Here 2 firewalls are used for the
construction of the DMZ. Among the two firewalls the first firewall is the front end or the perimeter. It allows the
traffic from the internal node to the DMZ. The next firewall is named as the back end or the internal firewall. It
allows the traffic from the external node to the DMZ and the vise versa. As there are two firewalls in the system
makes the system more secure. If one fails the other will help the providing the security. Generally the firewalls
must be chosen in such a way that they are provided by 2 different vendors. This method is called as the defense of
the depth.
(b)
The next model is the DMZ with the NAT network address translation.
Here you can see the two DMZ systems with the NAT. This is a more advanced system which not only provides
security but also very high-speed data access due to the presence of NAT.

The NAT application is explained through the above model. Here the request from the system 1 and 2 are allowed.
But the 3rd one is not allowed. Similarly, the public access is denied for some systems.
4. Security
(a) MITM is abbreviated as a man in the middle attack. This is a secret attack which is done in the altering the
communication between the two directly communicating systems. Here the control of both users is done by the
attacker only. The wifi usage is one of the kinds of example, which is done from the reception end. Here the attacker
may target one end or both the ends. Here the second case is the most worst case. The encryption or encoding from
both the ends is necessary for avoiding these kinds of problems in the data communication. The encoded or
encryption key will help to decode or decrypt at the receiving end [8]. This will end the problem of the middle
attacks. The next one is known as the replay attack. The other name for the replay attack is the play back attack.
Here the valid data is misused by sending the same data again and again or by delaying a data. This can be done
from the receiver end or from middle.
(b)

The two possible way of attack is with the tagging and without tagging.
1. No tagging
Here the tagging is not present and hence there is every possibility of the attack. Initially, the data request is sent
from A to B without tagging. Now due to lack f encoding or encryption, there is a possibility for the middleman
attack or play back attack to either side. Hence this is not suitable. Then the B will accept the request and will send
the public key certificate. Again there is an addition of new data in the system. In the third step the secret data i.e.
item number, price of the product, card details etc [ 6]. Then the B will send final data to the A in a final stage. Here
the encryption is not there means it’s a very tragic condition.
2. Tagging with codes
In this phase, the tagging is done in the codes. The data encryption and encoding at the source end and the
decryption and decryption at the receiver end are done. The codes must be secret and it should not reveal to the
third person. When the third person from the internal non trusted person or the cyber attacks may take a chance for
the data lost. Or else in all the other situations, the data is safe and the attacks are not possible [14].
5. Multimedia networks
The multimedia data generally consists of audio data, video data and sometimes the mix of both. The multimedia
data are generally a continuous data. The multimedia data consists of following. They are generally voluminous. The
multimedia data are a real-time, which is synchronization with the both audio and the video. The multimedia
generally interactive. Some of the best examples of the interactive are the video conference which should be
happening at real time without any delay and the other best example is the interactive TV. The multimedia are
sometimes burst also, i.e. it is a video on demand. But apart from this multimedia has 3 big challenges. Some of
them are There will be a delay in any systems. It is not possible to have accurate or no delay systems. The delay will
be varied from system to system and from machine to machine. Here the main aim of the person must be the
smallest possible delay. General delay in the apps is ranging from 5 seconds to 10 seconds. The delay may produce

the data congestion. One must take care to avoid the data congestion in any form or data congestion due to the
delay. The next concept is the packet jitter which tells about the variability of the packets of data in the same
stream. The service of the internet is not varied and hence the data delays are not possible to stop. If the same
vendor can provide the data variation one can stop the delays for the selected subscribers. The care must be taken
for the differentiated services.
a. Explain whether the challenge can be addressed in multimedia networking and how it is handled.
I )Packet delay
Packet delay and packet jitter are two common methods which will be occurring in the voice over data generally.
This also happens in the text and image data also. The care must be taken for avoiding theses steps. The jitter is not
suitable for the voice application for the average user. The delay can happen in any point to point of the network.
Generally, delay can be measured in two possible ways. The first one is one way and the next one is the round trip
delay. The one-way delay calculation is very expensive. It requires very costly equipment and best infrastructure. It
is not possible in all the cases. But cost involved in the round trip delay is very less with the equipment of finite or
less cost. Generally, the one trip delay and the round trip delay are taken as average for the final delay
measurement.
ii) Packet jitter
The next kind of thing in the packets analysis is the packet jitter. The packet Jitter is kind of variation in the delay
from a certain point to another point. The delay in the data must be varied in a great way if it happens the qualm
any of the services will be reduced in a great way. There is a concept known as the depth of the jitter which will give
the depth of voice quality.
iii) Packet re sequencing
The wireless and wired communication uses the data transmission in the form of packets of data. In the packets
form the packets will follow certain protocols and the algorithms. In this, the data will be sent in the form of packets
in all the direction and in a random path without following sequence. At the receiver end the data received will not
be in order and hence the data must be arranged in the proper sequence known as the data resequencing. This
process needs the order followed at the transmission end, which helps in the successful recovery of data. This
method is done in all the system for the data collection and the data arrangement [13].
iv)Packet loss
The packet loss is a phenomenon in which the packets of data are lost in the data path which inturn degrades the
performance of the system. Packet loss is found in all kinds of data.

(b) Three types of multimedia networking are:
Some of the common application of the multimedia is internet. On the internet, we can find the 3 basic
classifications of the multimedia. The first one is the streaming stored audio and the streaming stored video. The
next one is the streaming live audio and the streaming live video. The third and the final classification is the
streaming live audio and the streaming live video. Some of the common characteristics of the above are the delay
sensitivity, the next one is the end to end to end in the packet delay. The final form of it is the packet jitter. The
stream videos are generally having the tolerance to the packet losses. There are a minor disturbance and the
occasional packet loss. In the normal data transmission it will not tolerate the losses. It will not also tolerate the
delay variations.
i)
Streamed live multimedia: Internet radio, internet talk show, Live event, live telecast of sports. Interactive
multimedia: IP telephone, The video conferencing, distributed interactive things like video conferencing.
ii)
Let us now discuss the stream stored multimedia. The streamed multimedia is generally having the audio and video
files stored on the server. The users will request the audio and video of their own demand for the data and the
server will send the data to the user on demand. The next one is the streamed live multimedia. The streamed live
multimedia is a kind of live telecast on the internet. It contains the multimedia data like audio, video, text and
sometimes the combination of all. This process requires the camera for the recording and coverage, the encoder for
the digitize a content. Along with this, a playback buffer is also facilitated. Here the 10 seconds lag in the system can
be covered and the delay will be reduced as long as possible. The best example of this kind is the internet radio
where many talks are found in this. The options like fast forward of the data, rewind of the data, a pause of the data
and the record of the data are found. The final one is the interactive multimedia. In this, they have a certain end to
end delay requirements. For the audio requirements, if the delay is in the range of less than 150msec then it is in
the category of good, if the delay order is in the range of fewer than 400 msec then it is termed as OK. This has
many features like the packetization and the delays are very high in the system. The higher delays will lead to the
impair interactivity [12]. There is also a session start known as the initialization. The encoding algorithms also
required here. Some of the applications of this type are listed below. They are video conferencing, IP telephone and
some distributive interactive.
(c)
i) There are many techniques for the data storage of which the first one is the image compression. Generally, the
data compression is applicable for the digital data only. It is not applicable for the analogue data. Generally, the
compression performed to reduce the storage cost or the transmission cost. Some of the methods for the lossless
compression of the image are run-length encoding. It was one of the default methods for the BMP, TGA and TIFF.
The next one is the area in image compression, the area of the image is greatly compressed. There are some
predictive coding also used. The next of its kind is the entropy encoding. Some kind of the adaptive dictionaries was
also used. The chain codes will also be used in the system. The other kind of technique is the lossy compression. The
first one is associated with the colour space. The next one is the transform coding which is using some mathematical

operations like Fourier transform, Laplace transform and another kind of transforms for the domain changes. The
next one is the chroma sampling which is associated with the colours of the images and the video settings like
bright, contrast. The final one is known as the fractal compression.
ii)
Let me discuss the problem in two aspects. The first one is the picture version nd the second one is the video version
for the zoom. Here the pictures are more quality oriented than the video. The pictures taken with the best cameras
are given to the server. But the high-quality images occupy more space compared with the other low quality. Here
the images are compressed in the digital format. Now compressed images are zoomed means it cannot give the
same original feel. And hence the data must be altered in such a way that the quality must be varied. The next
aspect is the video. In the video, the zoom issues will happen at the time of recording. Here the recorded data can
be compressed then the quality issues start again. But the Video zooming is not possible. Hence the uploading
precaution is the only solution.
6. IP Header
The IP header is a part of the IP packet which has some kind of information at the starting. This header will have
many pieces of information like the source address and the destination address. Basically, in present day, they use
two different headers. First one is the IPv4 and the next one is the IPv6. The IPv6 has more space.
(a)
i) Strict Source Route.
The strict route path is a kind of path the packets of data must follow the strict or definite path. The packets must
finally go to the destination. This is used for the debugging options. It has many other applications also.
ii) Record Route.
The record routing is the process in which the route is recorded for the packets of data. Generally in the internet
data checksum if the data has a finite route that is the record route then the data will freely flow through the
suggested route. If not has to apply algorithms for the data transmission to send the data for the unknown
environment. Sometimes the known data might be full then it has to wait for the route clearance and then has to
pass the data. Or else the packets of data must choose an alternate path.

(b)
i) Identification: The identification is generally of 16 bits. This will use the IP datagram’s. The data value is
incremented or decremented depending upon the algorithm followed by the routers.
ii) Flag: The flags are generally 3 bits in length. The first bit is kept reserved. The second bit is called as the do not
fragment bit. The third bit is known as the more fragment bit.
iii) Offset: The fragment offset is generally 13 bits. This has fragment offset of 8 bytes at the start of IP datagram.
This is used in the reassembly of the fragmented data.
(c)
Given the packet offset values is 100, the header length is 20, the value of the total length is 40. The first-byte
number is 4 and the last byte number is 31 according to the concept of the above figure.
(d) Why is there a restriction on the generation of an ICMP message in response to a failed ICMP error message?
Typ
e
Description ICMP Message Types
0 Echo Reply (Ping Reply, used with Type 8,
Ping Request)
3 Destination Unreachable

4 Source Quench
5 Redirect
8 Echo Request (Ping Request, used with Type
0, Ping Reply)
9 Router Advertisement (Used with Type 9)
10 Router Solicitation (Used with Type 10)
11 Time Exceeded
12 Parameter Problem
13 Timestamp Request (Used with Type 14)
14 Timestamp Reply (Used with Type 13)
15 Information Request (obsolete) (Used with
Type 16)
16 Information Reply (obsolete) (Used with
Type 15)
17 Address Mask Request (Used with Type 17)
18 Address Mask Reply (Used with Type 18)