MP3 Files

                             

     MP3 files are basically compressed versions of CD's. A compression system was developed by the moving picture experts group that was used for video data. One of the subsystems for this was to compress sound (MP3).  MP3 can compress a song by a factor of 10 or 12 and still have it sound close to the CD quality.The main goal of MP3 is to compress a CD quality song so it can be easily stored. A 30 megabyte sound file can be reduced into a 3 megabyte sound file in MP3 format.
     To further understand MP3, a person should understand how a CD works. Music is sampled 44,100 times per second. These samples are 2 bytes long. This means that the average 3 minute song on a CD is around 32 megabytes. This is where MP3 comes in. The 32 megabyte song is compressed into a 3 megabyte song in order to make downloading speed faster and storage easier. the biggest concern with MP3 files are if they will match the Cd quality. It is possible to compress a song and still have it sound like CD quality. this is done by using a technique called perceptual noise shaping algorithm. It is perpetual because MP3 format uses characters of the human ear to design the algorithm. Certain noises cannot be heard by the human ear and certain noises can only be heard by the human ear. By using all of these factors, parts of the song can be eliminated without hurting the quality of the song.

Source: http://computer.howstuffworks.com/mp31.htm

                             

Wireless Network Precautions

                                            

      Many people and computer companies are starting to go wireless to make internet more convenient and cut the cost on wired equipment. Wireless networks are extremely convenient because wireless internet means hot spots. Hot spots are areas that have free public wi-fi. With public wi-fi though comes problems. The problem with hot spots is that hackers can steal personal information due to the fact that no passwords are needed to hook up to the internet. The reason why hackers are able to steal information from people who use hot spots is because hot spots turn off the security.      There are ways to prevent hackers from stealing information.
     To prevent hackers from stealing personal information, internet users should take certain precautions. People who use wireless internet should passwords on their home screen to stop hackers from getting access to their home screen. Other general internet precautions include securing the computer and the router. Putting a password to the internet router secures the internet connection. The use of encryptions is also useful because it scrambles information over the web into a code that is not accessible to others. Users should also install anti-virus and anti-spy software as well as a firewall. Limiting access to a persons wireless connection allows the user to pick and choose which devices are allowed on the network.

Source: https://www.onguardonline.gov/articles/0013-securing-your-wireless-network

                                  

Cloud Computing

                               


     Cloud computing systems are divided into two different sections, the front end and the back end. These both connect to each other through a network. The front end is the end the client sees and the back end is the "cloud" section of the system. The front end includes the users computer or computer network and the application required to access the "cloud". The back end of the system consists of various computer servers and data storage systems. This creates the cloud computing system.
     A central server administrators the system. this means that the administrator monitors traffic and client demands to make sure everything is running correctly. The cloud computing system also has a protocol and uses middleware. Middleware allows networked computers to be connected. The cloud can sometime break down so copies of all of the data is made in order to recover data. The cloud actually has many different uses. Cloud computing systems allows clients to access apps from anywhere at anytime. Costs of hardware goes down as well because the cloud reduces the need for advanced hardware. It also gives companies the option to store data on someone else's hardware.

Source: http://computer.howstuffworks.com/cloud-computing/cloud-computing1.htm


                            

Internet Filters

                                


     Internet filters are software tools that help monitor web content viewed on a specific computer or network. These filters operate on a series of categories. Filter companies utilize the categories to create filter profiles. these profiles are categorized into adult filters and children filters. Adult profiles allow most content, with the exception of nudity, through the filter. children profiles allow things that are appropriate for children. this excludes violent images, nudity and explicit language. If a site is not categorized, it may be blocked.
     Librarians mainly use internet filters. Library filters allow the administrator to pick and choose what categories to block. Home filters do not really allow this access. Most filters have a mechanism in them to override blocked pages by using the administrator password. This mechanism allows the user to modify the companies filter classification systems to more closely match library settings. Parental control software allows parents to monitor what their children do on the internet. This type of software can help children stay off of porn sites, social network, and potentially keep them away from cyber bullying.

Sources: https://infopeople.org/resources/filtering/how
               http://www.microsoft.com/security/resources/internetfilters-whatis.aspx
               http://www.pcmag.com/article2/0,2817,2346997,00.asp

                        

Radio Frequency Identification

                       


     Radio frequency identification is the wireless use of electromagnetic fields to transfer data for the purpose of tracking and identifying tags attached to an item. It is somewhat like a bar code, but it does not need to be within sight of the reader. Radio frequency identification is used frequently in industries. It is used to keep track of items that are on the assembly line. It is also used track goods and track airport baggage.
     Radio frequency identification works by sending a signal between the tag and the reader. tags may be either read only or have serial numbers already build into them. There are two types of readers. these two types are active reader passive tag and active reader active tag. Active reader passive tag transmits interrogator signals and also receives authentication replies from passive tags. Active reader active tag uses active tags awoken with and interrogator signal from the active reader. It is signaled by using wave lengths.

Source: http://en.wikipedia.org/wiki/Radio-frequency_identification

                                           

Digital Image Steganography

                           

     Digital image steganography works by adding secret bits to an image file. This technique is not frequently used so many people do not know how to decode it. This makes the technique a favorite among hackers because it is hard to decode. This makes it a good method of transmitting business or personal information on many different outlets such as e-mail or social media. There are two different approaches to digital image steganography. One is by adding extra bit files and the other approach is using the the least significant bit (LSB).
     Adding bit files is one approach that is as simple as adding extra bits to a file. Hidden messages can appear in the file header, which contains information on the file. Every file has a predefined "end of file here" mark. The secret message could be attached after the end of the file. files will not be modified, but an grow in size. Outsiders with access to the original file could easily see that there is a hidden message hidden inside of the file. Using the least significant bit is the other approach. This approach is simply the replacing of unimportant bits of the file that will not alter the image.

Source: http://www.itworld.com/article/2826840/security/crash-course--digital-steganography.html
                              

Computer Forensics

                    

     Computer forensics is the application of investigation and analysis technology in order to gather and preserve evidence. In other words, computer forensics is used to gather evidence that can be used inside of a court room. The main goal of computer forensics is to perform a structural investigation while still maintaining a chain of evidence to find out who is behind who is behind the problem that is happening in the computer. Before the device is looked at, experts make sure that the computer is isolated and not contaminated.
     Once the device is isolated and clear of any sort of contamination's, investigators make a copy of the device's storage media. This is done to preserve the original copy of the storage media. once a copy has been made, it is locked in a safe to maintain it's condition. Once the condition is maintained, investigators use different techniques to examine the copy of the storage media and search for hidden folders. Any evidence that is found on the copy is documented and verified with the original copy in preparation for legal proceedings that involve discovery, depositions or litigation.

Source: http://searchsecurity.techtarget.com/definition/computer-forensics



                                        

Packet Analyzer

                                           

     A packet analyzer is used to monitor, intercept, and decode data packets as they are transmitted across different networks. They are also called packet sniffers,protocol analyzers and network analyzers.  Packet analyzers can be either hardware or software. This means that packet analyzers could be physical equipment or be already set inside of the computers processor. Packet analyzers are used to help IT teams to monitor and filter network traffic.
     Another function of packet analyzers is the fact that they can be used in the form of "attacks". These   attacks can involve someone using a packet analyzer in a promiscuous way. These attacks allow hackers to access user log in, financial information and e-mail. These attacks are ways for hackers to gain important information that would never be seen by the public. People who use free wi-fi, such as hot spots, are at a high risk for these attacks. To avoid these attacks, users should use secure internet and put a password on all of their personal devices.

Source: http://www.veracode.com/security/packet-analyzer