Networking Questions And Answers Essay.

a) Forouzan identifies one of the advantages of protocol layering as allowing intermediate devices to be less complex by not requiring all layers Given that modern routers, switches, and other intermediate devices often provide web interfaces for administering/configuring the device:

1. i) Explain why all layers are required to be present for such devices; and
2. ii) Briefly discuss whether Forouzan’s identified advantage is still relevant.

b) In the Week 1 Class Slides in CloudDeakin, on page 49 is a figure illustrating the encapsulation and decapsulation of data as it moves from source host to destination host. The router is illustrated as having (i) two physical layers and (ii) two data link layers. Explain why these are required and describe how they would be used when a datagram passes through the router.

a) Consider creating a new type of network where the network cable (copper) has a large bandwidth and will be shared between several users.

1. Briefly describe how this network could be constructed either as a low-pass channel using TDM, or as several bandpass channels using FDM.
2. Identify one advantage and one disadvantage for each approach (note that it is possible that an advantage for one approach could be a disadvantage of the other approach).

b) You are employed by an organisation that stores and processes large volumes of highly sensitive data. After moving to new premises (a new building), you discover that the wired network between the data storage units and computation units is much higher latency than previously. Your colleague suggests using an ad-hoc wireless network between the two units will resolve the matter.

1. Briefly explain two potential problems with this approach.
2. Considering each of the four components of latency (propagation time, transmission time, queuing time, and processing delay), identify and explain one possible cause and how to resolve it.

a) The ARP protocol is used to identify an Ethernet address for a given IP address and the information discovered using this protocol is temporarily kept by a device in its “ARP cache”. Consider eliminating the ARP protocol by having devices periodically broadcast their Ethernet and IP addresses instead, and explain the advantages and disadvantages of this approach.

b) Referring to the Week 3 slides and training videos for examples of CRC and Internet checksum calculations:

1. Demonstrate the generation of the CRC code for the following input:
2. Demonstrate the generation of the 16-bit Internet checksum for the following input:

a) Consider configuring an IP address on a router and a switch.

1. Give an example of the commands used to configure an IP address on both a router and a switch. Use your own IP address and subnet mask (do not re-use those that appear on the practical task).
2. Briefly explain why the switch’s IP address is not applied to a physical interface.

b) Briefly explain the problem with the telnet tool (Week 2 practical discussion question 5) and identify an alternative tool and explain how it solves/eliminates this problem.

c) Briefly discuss the need for the IPCP protocol and describe what it is used for.

OSI Layering and Protocol Interactions

All the layers of the OSI layer is required to be included and the protocol layering is important for interacting with the different layers. Each of the multilayer programs in the devices used for networking consists of the seven layers of the OSI model. For the operation of the switch the physical and the data link layer is the most part in charge for conveying the information to the diverse connections associated with it. The two gadgets speak with each other by means of the data link layer and the physical layer is utilized for correspondence between two unique systems. For proper working in the network the data is passed using the router and the switch all the layers are required to be included for transmission of the data packets[1]. The network layer is used for identification of the next hop address and sending the packets to the next link. The different services are dependent on the different protocols such as controlling the congestion and flow. The router operates on the different OSI layers such as physical, data link and network and is used for encapsulation of the data packets and sending it to the destination node.

The advantages identified includes all the layers of the OSI model and the data is encapsulated and the transmission is secured with the use of the protocols. The physical layer is utilized for getting and transmitting the crude bits. The system for transmission is connected for encoding the flag and expanding the security[2]. The data link layer is utilized for evacuation of the errors in the transmission of the information and foundation of the connection between the hubs. The network layer is utilized for directing and mapping the consistent and the physical address. The transport layer is used for ensuring the delivery of the data packets to the destination address and controlling the message traffic. The session and the presentation layer is used for termination and the maintenance of the connection and encrypting the data sent over the network. The application layer is used for sharing the resources and access the files remotely for the management of the network components[3]. The HTTP protocol can be used for remote access and redirect the data traffic from the different network devices such as the switch and the routers.

For the development of the network using the low pass channel the frequency division multiplexing and the time division multiplexing is required to be analyzed. The different algorithm used for the development of the network is evaluated for the development of the network. The low pass channel is used for communication in the local area network. The frequency division multiplexing is used for carrying the analog signal and for the low pass channel the frequency starts from zero and for the band pass channel the frequency the frequency cannot be zero. It can be applied as a filter for the accommodation of the bandwidth of the radio signals. For the transmission of the digital bit stream pass band communication is used. The low pass channel can be used for the construction of the network because there is no need of modulation and thus the data transmission speed is much greater than the other bandpass [4]. The optical fiber cable uses the low pass filter for transmission of the data and avoiding the congestion.

Developing a New Type of Network

The advantage and disadvantage identified for the application of low pass using time division multiplexing and frequency division multiplexing are as follows:

The low pass filter for TDM can be applied on noisy environment and multiple stream of data can be put into a signal for transmission.

In case of FDM the frequency can be shared with a large group of user and different carrier of frequency can be modulated together.

The continuous signal can be handled efficiently with the application of the time division multiplexing because extra guard time is required to be added for the synchronization of the signal [5].

In case of FDM the signals can be distorted due to intermodulation and problems of interference can also occur.

The potential problem identified for the application of the ad-hoc wireless network between the data storage units and the computational units are as follows:

• The nodes connected in the network may not be visible to the other nodes connected in the network with the application of the wireless ad hoc network- The loss of the wireless signal or weak signal can cause low visibility and decrease in the performance of the network.
• The wireless ad hoc network have limited bandwidth and speed- The speed and bandwidth of the wireless network depends on the standards of the wireless device and its speed is limited and thus can affect the accessibility of the data residing in the datacenter of the network.

1. The advantage and the disadvantage of periodically broadcasting the Ethernet and the IP address instead of the ARP protocol are as follows:

• It reduces the utilization of the bandwidth and increases the efficiency of the current network because the requirement of the resolution of the mac address is eliminated and a checking is done for the devices connected in the network.
• The ARP table is compared time to time for analysis of the nodes and finding problem in the network and identify the cause for delay in the network and drop of data packets in the network.

• The address can be used by other devices and can communicate with the network and access the data packets in the network.
• The ARP cache table is required to be refreshed and it is inappropriate for larger networks with more number of nodes connected in the network because with the increase in the number of nodes the broadcasting request increase that causes generation of huge data traffic in the network.

1. i. An example for the configuration of the IP address on the router and the switch are as follows:

Router>

Router>en

Router#config t

Enter configuration commands, one per line.  End with CNTL/Z.

Router(config)#int fa 0/0

Router(config-if)#ip add 192.168.0.1 255.255.255.0

Router(config-if)#exit

Router(config)#exit

Switch

Switch>en

Switch#config t

Switch(config)#int vlan 1

Switch(config)#int fa 0/0

Switch(config-if)# ip add 192.168.0.3 255.255.255.0

Switch(config-if)#exit

Switch(config)#exit

The IP address of the switch cannot be applied on the physical interface because the switches uses the content accessible memory and it can only broadcast one domain without configuration of the vlan. It can be utilized for associating more than one hubs in the distinctive system. The principle purpose behind the not having any significant bearing the IP deliver of the change to a physical interface is the security of the system[6]. The switch does not support NAT and application of the IP address of the switch in the physical interface compromises the security enabling the hacker to intrude in the network.

The main problem identified for using telnet tool is that many of the server does not allow the use of telnet and it is required to be enabled for using the tool. It also have security problem because the session established between the client and the server is not encrypted and the hackers can access the TCP/IP data packet that is communicating between the hosts including the hostname, username and the passwords.

As an alternative of the Telnet the SSH can be used and it secures the password and the identity and allows secure login between the client and the server for transferring the files and data [7]. It operates on the same concept of the telnet but the only difference is that the transmission is encrypted and increases the efficiency of the remote management of the network.

ARP Protocol and Internet Checksum

The IPCP stands for internet protocol control protocol and it is a network control protocol used for the configuration and the establishment of the IP over the P2P link. The IPCP convention is utilized for DHCP pool parameter and portion of the IP deliver consequently to the hubs associated in the system. It can likewise be utilized for incapacitating the modules of the IP conventions at both the closures of the P2P connect. A specific IP address can be requested from the peer and it can also be used for suggestion of the IP address. For the configuration of the IPCP the link control protocol can be used and the IP data can be used for carrying the payload of the PPP frame. The IPCP negotiates with the optional peering IP address and succeed even though the peer does not include the IP address option in an IPCP configuration requesting for dynamic and static, and tunneled, and terminated Point-to-Point Protocol over Ethernet (PPPoE) users.

References

Amir S and others, 'RCM: A User Friendly Router Configuration Machine' (2013) 69 Wireless Personal Communications

Ferrarotti F, Hartmann S and Link S, 'Efficiency Frontiers Of XML Cardinality Constraints' (2013) 87 Data & Knowledge Engineering

Li X, Physical Layer Watermarking Of Direct Sequence Spread Spectrum Signals

Ning Z, Song Q and Yu Y, 'A Novel Scheduling Algorithm For Physical-Layer Network Coding Under Markov Model In Wireless Multi-Hop Network' (2013) 39 Computers & Electrical Engineering

Rut J and Bartoszuk M, 'Visualization Techniques For Production Processes Using The Communication TCP/IP Protocol' [2016] Mechanik

Sun Y and Kim M, 'High Performance Table-Based Algorithm For Pipelined CRC Calculation' (2013) 8 Journal of Communications

Umar S and others, 'Attacks Of Denial-Of-Service On Networks Layer Of OSI Model And Maintaining Of Security' (2017) 5 Indonesian Journal of Electrical Engineering and Computer Science

[1] Yan Sun and Min Sik Kim, 'High Performance Table-Based Algorithm For Pipelined CRC Calculation' (2013) 8 Journal of Communications.

[2] Xiang Li, Physical Layer Watermarking Of Direct Sequence Spread Spectrum Signals.

[3] Zhaolong Ning, Qingyang Song and Yao Yu, 'A Novel Scheduling Algorithm For Physical-Layer Network Coding Under Markov Model In Wireless Multi-Hop Network' (2013) 39 Computers & Electrical Engineering.

[4] Flavio Ferrarotti, Sven Hartmann and Sebastian Link, 'Efficiency Frontiers Of XML Cardinality Constraints' (2013) 87 Data & Knowledge Engineering.

[5] Samreen Amir and others, 'RCM: A User Friendly Router Configuration Machine' (2013) 69 Wireless Personal Communications.

[6] Syed Umar and others, 'Attacks Of Denial-Of-Service On Networks Layer Of OSI Model And Maintaining Of Security' (2017) 5 Indonesian Journal of Electrical Engineering and Computer Science.

[7] Joanna Rut and Marian Bartoszuk, 'Visualization Techniques For Production Processes Using The Communication TCP/IP Protocol' [2016] Mechanik.