Networking Homework Help: Explain why security is important for WLANs, even more ...

Q)Explain why security is important for WLANs, even more so than for wired networks. 

Sol:

More security is needed and security is very much important in case of wireless LANs, when compared to wired LANs. The main reason behind this is in case of wireless LANs by making use of the wireless authentication of the authorized wireless user any one can make use of it also hacking the wireless network is very easy if it is not password protected. Since in most of the WLANs the users are not protected by a unique password, since wireless LANs are always used in case of places like college campus or office campus where multiple users can access the network. Hence in case of wired LAN there is a need for the dedicated channel or cable through which every user can get connected to the network whereas in case of wireless LANs there is no need for it, sometimes it will not even ask for any security passwords. Hence any user can get connected to the network and use it without paying for it. As a result more security is important for WLAN’s when compared to Wired LAN.

Networking Assignment Help: What specific steps can be taken to improve security in WLANs...

Q)What specific steps can be taken to improve security in WLANs?

Sol:

 The below steps can be taken to improve the security in WLANs:

a) Initially wireless network has to be authorized and authenticated.

b) Also all the users try to get connected to that particular has to be authorized and authenticated.

c) Every user connected to the network has to be uniquely identified by their own unique username and password.

d) Multiple users with same username and password should not be allowed to connect to the network.

e) Every user has to be properly disconnected so that no one in queue must be able to continue to get connected to the network with their username and password.

Think and Answer Assignments: Minicase IV Household Wireless page....

Q)Your sister is building a new two story house which measures 50 feet long by 30 feet wide and wants to network her family’s three computers together. She and her husband are both consultants and work out of their home in the evenings and a few days a month.  Each has a separate office with a computer, plus a laptop from the office that they occasionally use. The kids also have a computer in their playroom. They have several options for networking their home:

a) Wire the two offices and playroom with Ethernet cat5e and put in a 100Base-T switch.

b) Install one Wi-Fi access point ($85) and put Wi-Fi cards in the three computers (the laptops already have Wi-Fi)

c) Any combination of these options

There are many possible solutions to this problem.  What would you recommend, considering their current hardware configuration as well as potential expansion? Justify your recommendation.           

Sol:

The best possible solution is to go for installation of Wi-Fi access points followed by installation of Wi-Fi cards for the desktop computers. Anyways laptops will definitely have Wi-Fi inbuilt so there is no need for separate installation of the cards in laptops. The reason behind this is looking at the future definitely the desktops are getting replaced by laptops. Also laptops are portable, which means we can carry them any where we need but if they are connected to some network cables then we will not be able to access the network wherever we carry the laptops. Also in case of desktops if we place it in 1st floor but tomorrow we need it in the last floor then there is need to work on the network connectivity in it only labor is involved in shifting but network connectivity is always there since it is independent of the location within the office campus or two story house limits. Hence the recommendation here is to go for Wi-Fi connection.

Networking Homework Help: There is an ever growing range of physical media being offered such as fiber...

Q)There is an ever growing range of physical media being offered such as fiber, coax, satellite, IP over power lines, a number of wireless technologies, and more. Recently, the telephone companies announced 4G wireless communications and the IEEE has WiMax at Gigabit rates. What criteria would you use to select technologies for your business and for your home?

Sol:

The following are the criteria being used to select technologies for my business:

a) Multiple connections with maximum speed.

b) Higher bandwidth with lesser price.

c) Unlimited downloads with no additional charges.

d) Unlimited access within the coverage area irrespective of the machines being used.

e) Full time high speed networks without any congestion.

The following are the criteria being used to select technologies for my home:

a) Not more than two connections at a time.

b) Very lesser cost, irrespective of download limits.

c) Limited access but reduction in the monthly bill.

d) Moderate speed and bandwidth, irrespective of the congestion.

e) Lesser monthly rentals provided there are additional charges for download if it crosses the available limit.

General Assignment Help: How to define a portfolio of Outsourced information technologies services...

Q) How to define a portfolio of Outsourced information technologies services??

Sol: 

Portfolio of Outsourced Information Technologies services can be defined as identifying and understanding the customer requirements, also providing a way to communicate the value that the IT organization delivers to the business. The portfolio of IT services also allows the IT organization to say to the business, “Here is what we deliver to you”. Ultimately, it is the list of what customers ‘buy’ from the IT organization by paying the Organization.

Read and Answer: The International Centre for Radio Astronomy Research...

1) The International Centre for Radio Astronomy Research

Sol:

The International Centre for Radio Astronomy Research is a collaborative centre placed in Perth, Western Australia. They are already achieving research excellence in both astronomical science and engineering. The International Centre for Radio Astronomy Research has grown steadily from its launch in September 2009. An equal joint venture between The University of Western Australia and Curtin University, International Centre for Radio Astronomy Research has strong support from the West Australian as well as Australian governments and is working very closely with industry and research partners in Australia and in the entire world. Wireless internet (WIFI) inventor honored Curtin University has been recognized as Dr John O’Sullivan’s ground breaking work in astronomy and wireless technologies by bestowing John with an Honorary Science Doctorate. The latest telescope puts focus on high school discoveries where a new internet telescope was launched by State Education Minister Dr Elizabeth Constable at The Western University of Australia. Also
Sky Noise and Sensitivity Studies of Array Configurations and Antenna Elements were done for the Low-Frequency Band of the SKA.

Questions:

a) What is WIFI?

b) Expand ICRAR?

c) Internet telescope was launched by whom?

d) Who invented wireless internet?

Sol:

a) Wireless internet/wireless LAN.

b) International Centre for Radio Astronomy Research.

c) Dr. Elizabeth.

d) Dr John O’Sullivan

Read and Answer: De-noising sea noise data....

1) De-noising sea noise data

This work presents De-noising sea noise data and also how data from a marine seismic survey, which is highly contaminated by noise, was de-noised through the use of a time-frequency filter. In addition to the present standard work flow designed to remove cavitation noise, strumming noise and swell-noise. We introduce a new approach to track seismic interference. This is done by applying time-frequency de-noising on the slowness that gathers. As a motivation and background for the processing we also explain some of the techniques behind the generation of the many different noise types.

The end story is that even in case low if there is a low quality input data then also it can be turned into high quality seismic sections. Even though the dataset used is only one, the results and its methodologies represented here are considered to be general, and should be definitely applicable to a large number of seismic surveys.

Questions:

a) Name the two components which seismic data consists of? 

b) What is the second problem in this dataset?

c) What is the frequency range of swell noise?

d) What is the frequency range of hydrostatic pressure variation noise?

Sol:

a) signal and a noise component

b) Swell-noise

c) (1-10(15)Hz)

d) (0-1(2)Hz)

Read and Answer: Passive acoustic techniques to study sound producing fish species...

1) Passive acoustic techniques to study sound producing fish species

A wide variety of taxa fish produce sound. The behavior of Sound production gives an opportunity to study and analyze various aspects of fish biology, such as habitat selection and spawning behavior, in a very non-invasive manner. Passive acoustics is an active area of research called ichthyologic research. However, fish bio-acousticians have not published their research details in the fisheries literature. Therefore, fisheries scientists may not be aware of progress being made in this field completely or the potential uses for acoustic techniques passively. The physiological, behavioral and evolutionary aspects of sound production by fishes generally investigate the patterns of research publication on sound production by the fish and also review the literature which is based on the passive acoustic methods application to the research of fisheries and finally predicts and tells different ways of passive acoustic surveys which is being designed to optimize the quality and quantity of information obtained. Passive acoustic methods can be definitely attractive as well as alternative or it may supplement to the other traditional fisheries based on assessment techniques since they are non-invasive, and also can be conducted at low cost, which covers a large study area at temporal resolution and high spatial.

Questions:

a) Name the fish which produces sound?

b) Which are the three aspects of sound production?

c) Which acoustic method can be attractive?

d) What can be the Passive acoustic methods?

Sol:

1. Taxa
2. Physiological, behavioral and evolutionary aspects.
3. Passive acoustic method.
4. non-invasive

Read and Answer: The International Centre for Radio Astronomy Research...

1) The International Centre for Radio Astronomy Research

The CSIRO Wireless LAN story

CSIRO’s wireless LAN is one of the most leading technologies, and also most of you are already aware of the story. The technology lies at the heart of the most popular way of connecting computers without wires which is now known as wireless LAN. CSIRO has reminded very important and also lucrative always in terms of getting things done in the better manner. The Science and technology Industry Endowment Fund launched has been made possible by the success of CSIRO’s wireless LAN technology. Hence we can pay a particular tribute to everyone those who have made the Science and Industry Endowment Fund possible by creating CSIRO’s wireless local area network technology. Recently, CSIRO has sharpened its focus very well on Australia’s greatest opportunities and challenges through its National Research Flagships. CSIRO’s wireless LAN technology ranks as a major achievement in Australia, and it would be great enough to see significant objects related to the wireless LAN story which is being researched these days.

Questions:

a) Name the inventers of CSIRO WLAN?

b) Commercial board of CSIRO is chaired by?

c) Where was the CSIRO research carried out?

d) In which place in Australia the CSIRO WLAN was launched?

Sol:

a) Terry Percival, John Deane, Graham Daniels, Diet Ostry and John O’Sullivan.

b) Dr Terry Cutler.

c) In Australia.

d) National Museum of Australia.

The total number of partitions of a k-element...

Q) The total number of partitions of a k-element
   set is denoted by B (k) and is called the k-th Bell number.

    Thus B (1) = 1and B (2) = 2.
   Need to find B (k) for k = 4, 5, 6.

Sol:

We know that,

Where,

Is the Binomial Coefficient.

It is given by:

It’s given that B (0) =1; B (1) =1; B (2) =2

Hence for n=3, from the first formulae

B (3) =C (2, K) B (K) where K=0 to n-1

B(3)=C(2,0)B(0)+ C(2,1)B(1)+ C(2,2)B(2)

From the second formulae, C (2, 0) =2! /0! (2-0) = 1

C (2, 1) =2; C (2, 2) =1

Hence,

B (3) =1*1+2*1+1*2=5

For n=4,

B(4)= C(3,0)B(0)+ C(3,1)B(1)+ C(3,2)B(2) + C(3,3)B(3)

        = 1*1+3*1+3*2+1*5= 15

Similarly,

For n=5,

B (5) = 52

For n=6,

B (6) = 203

Looking for the solutions of few mathematics questions?

a) ABC' + B C' D' + B C + C' D = B + C' D

Sol:

LHS = (ABC’+BC)+ (BC’D’+C’D)

       =B(C+C’A) +C’ (D+D’B)

       =B(C+A) +C’ (D+B)

       =AB+BC+C’D+C’B

      =AB+C’D+B (C+C’)                //C+C’=1

      =AB+C’D+B

      =B (1+A) +C’D                        //1+A=1

      =B+C’D

      =RHS

b) WY + W' Y Z' + WXZ + W' X Y' = WY + W' X Z' + X' Y Z' + X Y' Z

Sol:

RHS=wy + w’xz’ + x’yz’ + xy’z

        =WY(1+XZ)+ w’xz’(Y+Y’)+ x’yz’ (W+W’)+ xy’z(W+W’)         //Y+Y’=W+W’=1+XZ=1

        = wy + wxyz + w’xyz’ + w’xy’z’ +wx’yz’ + w’x’yz’ + wxy’z + w’xy’z

        =wy + w’xyz’ + w’x’yz’ + wxyz +wxy’z + w’xy’z + w’xy’z’ + wx’yz’

        =wy + wx’yz’ + w’yz’(x + x’) + wxz(y + y’)+w’xy’(z + z’)

        =wy(1 + x’z’) + w’yz’ + wxz + w’xy’

        = WY + W' Y Z' + WXZ + W' X Y'

        =LHS

c) A D' + A' B + C'D + B'C = (A' + B' + C' + D')(A + B + C + D') = AC’+A’B +B‘C + D’

Sol:

RHS=(A' + B' + C' + D')(A + B + C + D')

        =A’A+A’B+A’C+A’D’+B’A+B’B+B’C+B’D’+C’A+C’B+C’C+C’D’+D’A+D’B+D’C+D’D’

        =A’B+A’C+A’D’+B’A+B’C+B’D’+C’A+C’B+C’D’+D’A+D’B+D’C+D’   //AA’=0; D’D’=D’

        = AC’+A’B +B‘C + D’+ A’C (B+B’) + B’A (C+C’) + C’B (A+A’)    //A+A’=1

        = AC’ (1 + B’ + B) + A’B (1 + C’ + C) +B’C(1 + A + A’) + D’    //1+A=1

        = AC’+A’B +B‘C + D’

        =LHS

Assignment Help: Case Study on...

Case study:  Consider a 500 gallon tank that needs to be filled when the level goes below 25 gallons and will stop when the level goes above 475 gallons.

Control systems can be either open-loop or closed-loop; each one of them has their own advantages and problems.  For the system described above:

1)      Describe how you would implement it using an open-loop system

To be continued based on the request, please feel free to write to us from contact us form or comment over here!!!

Assignment Help: Phases of the Moon Exercise...

In this exercise, you will investigate the cause of the phases of the Moon. The figure below shows an orbital diagram of the Earth-Moon system as viewed from above the Earth's north pole. Light from the Sun is coming from the left. Note that the drawing is not to scale.

Section I

Shade in the part of the Moon that is in shadow and the part that is not observable from Earth in each of the eight numbered positions. The first has been completed as an example. (Use dark shading for the shadow, light cross-hatch for the unobservable side.) 

To be continued based on the request, please feel free to contact us or comment on this post for more info on this question/answer

Chemistry Homework Help: How much more soluble is...

(a) How much more soluble is AgCl in 1 Molar NH3 than in water?
(b) How much more soluble is CaSO4 in 1 Molar HNO3 than in water?

Sol:

1) A chloride solution of metal reacts with silver nitrate solution to produce a precipitate. The precipitate is soluble in Ammonia solution:

Actually, NH3 complexes silver to make Ag (NH3)2, and this reaction is favorable enough to make AgCl dissolve (but not the much more insoluble Agcl. Hence Agcl is soluble in 1 molar NH3 to some extent.

2Agcl + 4NH3 ==> 2Ag (NH3)2 + cl2

2) CaSO4 is infinitely much more soluble in 1 molar HNO3. The reason is that the CaSO4 (mostly insoluble in water) is converted to Ca (NO3)2 which is very much soluble in water. As a result calcium sulphate is infinitely very much soluble in nitric acid.

CaSO4 +2HNO3 ==> Ca(NO3)2 + H2SO4

Assignment Help: VLSI, Electronic Design, Transisor & Wireless Telecommunication References

A Small Assignment on wireless telecommunications & few of its references:

Wireless Telecommunications

The growth in the field of wireless technology is very wide such that most of the stuffs in the world works as wireless, such that the expectation of the public in the world started increasing and the hard work started reducing since they expect the things to be done or executed easily without much hard work.

The development in the field of wireless telecommunication resulted in the development of the business in the field of information technology. This advancement helped the world to improve the communication between different countries and different cities. This resulted in fastest transfer of information between the public.

Due to the advancement in the field of wireless telecommunication, the wired communication started becoming outdated and the market for the mobile phones and wireless service providers started improving. Also the competition for the wireless service providers resulted in reduction of call rates in the wireless telecommunications which was quite high at the starting stages.

Capture interdependence in-between traffic, transmission technology, and spectrum as well as infrastructure and service quality

Here we are talking about the traffic during the peak hours of data transmission, where it might also result in congestion. The advancement in the field of wireless telecommunications resulted in capturing the interdependence in between traffic, where the channels allocated for the wireless communication is not fixed, but it’s dynamic. Hence there is reduction of traffic in case of wireless communication when compared to wired communication. The transmission technologies are used to transmit the wireless signals using the wireless towers so that the wireless devices will be able to capture the signals within the limits defined. Initial investment for the infrastructure related to the set up of the wireless communication systems will be bit high but later on it will be very easy to maintain as well as the amount of revenue generated from it will be very high.

Incorporate congestion and also minimum infrastructure needs

But due to development in the field of information technology the ideas related to cost cutting was gathered and customized to form various models. These models resulted in delivering better and minimum infrastructure need along with small investments to set up wireless systems and also these models resulted in very cheap local and international calls which are congestion free. Hence minimum infrastructure needs resulted in lesser investments for wireless service providers and these service providers made the service available to almost all the general public by reducing the initial cost of purchase of the devices and also by keeping lesser price for calls.

Relative profits and revenue as well as return on assets and market share to the changes in demand and transmission technology

The above developed model also helped in knowing about the relative profits earned by the wireless service providers for the initial investment made. As the market share and return on assets started reflecting due to the changes in the demand for the service, which also resulted in the further research and advancement in the technology of wireless telecommunications.

Finally we can say wireless communication is the boom for the field of technology and communications.

References on wireless telecommunications:

1) Tse, David; Viswanath, Pramod (2005). Fundamentals of Wireless Communication. Cambridge University Press. ISBN 0521845270.

2) Rappaport, Theodore (2002). Wireless telecommunications: Principles and Practice. Prentice Hall. ISBN 0130422320.

3) Molisch, Andreas (2005). Wireless telecommunications. Wiley-IEEE Press. ISBN 047084888X.

4) Goldsmith, Andrea (2005). Wireless Communications. Cambridge University Press. ISBN 0521837162.

5) ^ "Wireless Communication". sintef.no. Retrieved 2008-03-16.

6) Story, Alfred Thomas (1904). A story of wireless telegraphy. New York, D. Appleton and Co..

7) Hotspot (Wi-Fi), Wireless energy transfer, True wireless, Wireless security, Wireless access point

8) "Heinrich Rudolf Hertz". chem.ch.huji.ac.il. Retrieved 2008-03-16.

9) O'Brien, J. & Marakas, G.M.(2008) Management Information Systems (pp. 239). New York, NY: McGraw-Hill Irwin

10)         J.C. Bose, Collected Physical Papers. New York, N.Y.: Longmans, Green and Co., 1927

References on VISI design and EDA

1) VLSI design, 2007

2) VLSI Series, 2008

3) VLSI Design Reviews,2009

4) VLSI design methods, 2008

5) VLSI Design architecture, 2009

6) Electronic Design Automation Channels,2008

7) Kirti Sikri Desai (2006). "EDA Innovation through Merger and Acquisitions". EDA Cafe. Retrieved March 23, 2010.

8) Combinatorial Algorithms for Integrated Circuit Layout, by Thomas Lengauer, ISBN 3-519-02110-2, Teubner Verlag, 1997.

9) Electronic Design Automation For Integrated Circuits Handbook, by Lavagno, Martin, and Scheffer, ISBN 0-8493-3096-3, 2006

10)         The Electronic Design Automation Handbook, by Dirk Jansen et al., Kluwer Academic Publishers, ISBN 1-4020-7502-2, 2003

References for Transistors, amplifiers and analogue circuits design

1) "transistor". American Heritage Dictionary (3rd ed.). Boston: Houghton Mifflin. 1992.

2) J. Chelikowski, "Introduction: Silicon in all its Forms", Silicon: evolution and future of a technology (Editors: P. Siffert, E. F. Krimmel), p.1, Springer, 2004 ISBN 3-540-40546-1.

3) Lilienfeld, Julius Edgar, "Method and apparatus for controlling electric current" U.S. Patent 1,745,175 1930-01-28 (filed in Canada 1925-10-22, in US 1926-10-08).

4) "Transistor Example". 071003 bcae1.com

5) W. Heywang, K. H. Zaininger, "Silicon: The Semiconductor Material", Silicon: evolution and future of a technology (Editors: P. Siffert, E. F. Krimmel), p.36, Springer, 2004 ISBN 3-540-40546-1.

6) Verhoeven CJM, van Staveren A, Monna GLE, Kouwenhoven MHL and Yildiz E (2003). Structured electronic design: negative feedback amplifiers. Boston/Dordrecht: Kluwer Academic. pp. 10. ISBN 1-4020-7590-1.

7) Robert S. Symons (1998). "Tubes: Still vital after all these years". IEEE Spectrum 35 (4): 52–63. doi:10.1109/6.666962.

8) Singmin, Andrew (2001). Beginning digital electronics through projects. Newnes. p. 9. ISBN 0750672696. "Signals come from transducers..."

9) Carr, Joseph J. (2000). Secrets of RF circuit design. McGraw-Hill Professional. p. 423. ISBN 0071370677. "It is common in microwave systems..."

10)         Chen, Wai-Kai (2005). The electrical engineering handbook. Academic Press. p. 101. ISBN 0121709600. "Noise from an analog (or small-signal) perspective..."

References for Linear control systems.

1) Linear Control Systems, System overview 2009

2) Linear Control Systems, the complete reference, 2008

3) Introduction to Linear Control Systems, the introduction 2008

4) Numerical Methods for linear systems, Numerical methods 2008

5) Stability of linear control systems, Stability of LCS, 2008

6) Hierarchies of Linear control Systems, LC hierarchy 2007

7) Control Systems Overview, CS overview, 2007

8) Linear Control Systems with Matlab, Matlab implementation in LC 2008

9) Time scales of Linear Control Systems, LCS time scales 2007

10)         LCS with Laboratory, LCS and laboratory, 2008

Write-Ups Assignment Help: What is a little-know secret to the profitability of Amazon.com?

The below are few of the topics on which the write-ups of 300 to 500 words are expected:

1) What is a little-know secret to the profitability of Amazon.com?

2) Which of these characterized the strategies is the early days (and somewhat, still today) of electronic commerce?

3)Q)“Words carry the message. They would carry the same meanings with or without paragraphing. Therefore, paragraphing has no effect on communication.” Discuss your view of this statement and provide an example which supports your analysis. 

4)What is access matrix? For what purpose is access matrix used in general purpose OS?

4)Many people feel that the American government is out of touch with its public. Look at the branches of government and analyze this statement. 

Need an answer, Please comment on this post!!!

Write-Ups Assignment Help: JIT logistics/supply chain management for what...

Q) JIT logistics/supply chain management for what (now defunct) America automaker.

Sol:

JUST-IN-TIME LOGISTICS SUPPORT IS USED FOR THE AUTOMOBILE INDUSTRY since JIT drastically reduces the investment as well as also the total cost of the operation. In the early 1970s the United States automobile industry realized that the advantage of adopting the JIT would bring the US automakers where they were carrying $775 worth of the work in the process inventory for each of the car they built, but the Japanese carried only $150 of the amount. The only very existence of the Unites states auto industry which depended on the adopting of the JIT philosophy. Very efficient way of transportation methods were one of the critical to the effective JIT process.

Key issues of the transportation before the JIT include plant locations, were the role of the transportation along with the deregulation as well as the transportation regulation. The placement of the plants also changed as a solution of the implementation of the JIT.