Telephone
people have devised methods for communicating over long distances. The earliest methods involved crude systems such as drum beating or smoke signaling. These systems evolved into optical telegraphy, and by the early 1800s, electric telegraphy. The first simple telephones, which were comprised of a long string and two cans, were known in the early eighteenth century.
A working electrical voice-transmission system was first demonstrated by Johann Philipp Reis in 1863. His machine consisted of a vibrating membrane that opened or closed an electric circuit. While Reis only used his machine to demonstrate the nature of sound, other inventors tried to find more practical applications of this technology. They were found by Alexander Graham Bell in 1876 when he was awarded a patent for the first operational telephone. This invention proved to revolutionize the way people communicate throughout the world.
Bell's interest in telephony was primarily derived from his background in vocal physiology and his speech instruction to the deaf. His breakthrough experiment occurred on June 2, 1875. He and his assistant, Thomas Watson, were working on a harmonic telegraph. When a reed stuck on Watson's transmitter an intermittent current was converted to a continuous current. Bell was able to hear the sound on his receiver confirming his belief that sound could be transmitted and reconverted through an electric wire by using a continuous electric current.
The original telephone design that Bell patented was much different than the phone we know today. In a real sense, it was just a modified version of a telegraph. The primary difference was that it could transmit true sound. Bell continued to improve upon his design. After two years, he created a magnetic telephone which was the precursor to modern phones. This design consisted of a transmitter, receiver, and a magnet. The transmitter and receiver each contained a diaphragm, which is a metal disk. During a phone call, the vibrations of the caller's voice caused the diaphragm in the transmitter to move. This motion was transferred along the phone line to the receiver. The receiving diaphragm began vibrating thereby producing sound and completing the call.
While the magnetic phone was an important breakthrough, it had significant drawbacks. For example, callers had to shout to overcome noise and voice distortions. Additionally, there was a time lapse in the transmission which resulted in nearly incoherent conversations. These problems were eventually solved as the telephone underwent numerous design changes. The first phones made available to consumers used a single microphone. This required the user to speak into it and then put it to the ear to listen. Thomas Edison introduced a model that had a moveable listening earpiece and stationary speaking tube. When placing a call, the receiver was lifted and the user was connected directly to an operator who would then switch wires manually to transmit. In 1878, the first manual telephone exchange was opened. It served 21 customers in New Haven, Connecticut. Use of the telephone spread rapidly and in 1891, the first automatic number calling mechanism was introduced.
Long-distance service was first made available in 1881. However, the transmission rates were not good and it was difficult to hear. In 1900, two workers at Bell System designed loading coils that could minimize distortions. In 1912, the vacuum tube was adapted to the phone as an amplifier. This made it possible to have a transcontinental phone line, first demonstrated in 1915. In 1956, a submarine cable was laid across the Atlantic to allow transatlantic telephone communication. The telecommunication industry was revolutionized in 1962 when orbiting communication satellites were utilized. In 1980, a fiber-optic system was introduced, again revolutionizing the industry.
Background
Telephones still operate on the same basic principles that Bell introduced over one hundred years ago. If a person wishes to make a call, they pick up the handset. This causes the phone to be connected to a routing network. When the numbers are pressed on a touch-tone keypad, signals are sent down the phone line to the routing station. Here, each digit is recognized as a combination of tone frequencies. The specific number combination causes a signal to be sent to another phone causing it to ring. When that phone is picked up, a connection between the two phones is initiated.
The mouthpiece acts as a microphone. Sound waves from the user's voice cause a thin, plastic disk inside the phone to vibrate. This changes the distance between the plastic disk and another metal disk. The intensity of an electric field between the two disks is changed as a result and a varying electric current is sent down the phone line. The receiver on the other phone picks up this current. As it enters the receiver, it passes through a set of electromagnets. These magnets cause a metal diaphragm to vibrate. This vibration reproduces the voice that initiated the current. An amplifier in the receiver makes it easier to hear. When one of the phones is hung up the electric current is broken, causing all of the routing connections to be released.
Eiisha Gray
Elisha Gray was Alexander Graham Bell's principle rival, first for invention of the harmonic telegraph and then of the telephone. He was a prolific inventor, granted some 70 patents during his lifetime. Born in Barnesville, Ohio, on August 2, 1935, and brought up on a farm, Gray had to leave school early when his father died but later continued his studies at Oberlin College, where he concentrated on physical sciences, especially electricity, and supported himself as a carpenter.
After leaving Oberlin, Gray continued his electrical experiments, concentrating on telegraphy. In 1867, he patented an improved telegraph relay, and later, a telegraph switch, an "annunciator" for hotels and large business offices, a telegraphic repeater, and a telegraph line printer. He also experimented with ways to transmit multiple, separate messages simultaneously across a single wire, a subject that was also engaging the efforts of Bell. Gray prevailed, filing his harmonic telegraph patent application in February 1875, two days before Bell's similar application.
Gray now began investigating ways to transmit voice messages, soon developing a telephone design that featured a liquid transmitter and variable resistance. In one of the most remarkable coincidences in the history of invention, Gray filed notice of his intent to patent his device on February 14, 1876—just two hours after Bell had filed his own telephone patent at the same office. Western Union Telegraph Company purchased the rights to Gray's telephone and went into the telephone business; the Bell Telephone Company launched a bitter lawsuit in return.
Meanwhile, Gray had been a founding partner in 1869 of Gray and Barton, an electric-equipment shop in Cleveland, Ohio. This became Western Electric Manufacturing of Chicago in 1872, which evolved into Western Electric Company, which, ironically, became the largest single component of Bell Telephone in 1881.
The system of transmission presented describes what happens during a local call. It varies slightly for other types of calls such as long distance or cellular. Long distance calls are not always connected directly through wires. In some cases, the signal is converted
The electronic components of the telephone are sophisticated and use the latest in electronic processing technology. The circuit board is produced the same way that boards are made for other types of electronic equipment. The preprinted, nonconductive board is passed through a series of machines that place the appropriate chips, diodes, capacitors, and other electronic parts in the appropriate places. To affix the electronic parts to the board, a wave soldering machine is used.
to a satellite dish signal and transmitted via a satellite. For cellular phones, the signal is sent to a cellular antenna. Here, it is sent via radio waves to the appropriate cell phone.
Eiisha Gray
Elisha Gray was Alexander Graham Bell's principle rival, first for invention of the harmonic telegraph and then of the telephone. He was a prolific inventor, granted some 70 patents during his lifetime. Born in Barnesville, Ohio, on August 2, 1935, and brought up on a farm, Gray had to leave school early when his father died but later continued his studies at Oberlin College, where he concentrated on physical sciences, especially electricity, and supported himself as a carpenter.
After leaving Oberlin, Gray continued his electrical experiments, concentrating on telegraphy. In 1867, he patented an improved telegraph relay, and later, a telegraph switch, an "annunciator" for hotels and large business offices, a telegraphic repeater, and a telegraph line printer. He also experimented with ways to transmit multiple, separate messages simultaneously across a single wire, a subject that was also engaging the efforts of Bell. Gray prevailed, filing his harmonic telegraph patent application in February 1875, two days before Bell's similar application.
Gray now began investigating ways to transmit voice messages, soon developing a telephone design that featured a liquid transmitter and variable resistance. In one of the most remarkable coincidences in the history of invention, Gray filed notice of his intent to patent his device on February 14, 1876—just two hours after Bell had filed his own telephone patent at the same office. Western Union Telegraph Company purchased the rights to Gray's telephone and went into the telephone business; the Bell Telephone Company launched a bitter lawsuit in return.
Meanwhile, Gray had been a founding partner in 1869 of Gray and Barton, an electric-equipment shop in Cleveland, Ohio. This became Western Electric Manufacturing of Chicago in 1872, which evolved into Western Electric Company, which, ironically, became the largest single component of Bell Telephone in 1881.
The electronic components of the telephone are sophisticated and use the latest in electronic processing technology. The circuit board is produced the same way that boards are made for other types of electronic equipment. The preprinted, nonconductive board is passed through a series of machines that place the appropriate chips, diodes, capacitors, and other electronic parts in the appropriate places. To affix the electronic parts to the board, a wave soldering machine is used.
Raw Materials
A variety of raw materials are used for making telephones. Materials range from glass, ceramics, paper, metals, rubber and plastics. The primary components on the circuit board are made from silicon. The outer housing of the phone is typically made of a strong, high-impact resistant polymer. To modify the characteristics of this polymer, various fillers and colorants are used. The speakers require magnetic materials.
Design
Modern telephones come in many shapes and sizes, but they all have the same general features. They consist of a single handset which contains both the transmitter and receiver. The handset rests on the base when the phone is not in use. They also have a dialing system which is either a rotary dial or a touch-tone keypad. Recently, rotary phones have been phased out in favor of the more useful keypad. To alert the consumer that they have an incoming call, phones are equipped with ringers. A wide variety of specialized phones are also produced. Speaker phones are made to allow the consumer to carry on a telephone conversation
The individual parts of the telephone are assembled both automatically and manually. The transmitter and receiver are put together by machines. These parts are then fed onto the main assembly line and inserted into the molded headset. Similarly, the internal electronics, including the touch-tone pad, are inserted into the main housing and attached with screws.
without holding the handset. Cordless phones are also available. These models do not require direct connection of the handset to the base. Instead the user's voice is converted to radio waves and then sent to the phone base. This, in turn, gets converted to an electric signal and sent down the phone lines. Another type of common phone is the cellular phone. These phones use radio waves and an antenna system to communicate between phones.
The individual parts of the telephone are assembled both automatically and manually. The transmitter and receiver are put together by machines. These parts are then fed onto the main assembly line and inserted into the molded headset. Similarly, the internal electronics, including the touch-tone pad, are inserted into the main housing and attached with screws.
The Manufacturing
Process
Since there are so many different parts that go into making a telephone, the components are typically produced by different companies and then assembled by the phone manufacturer. The main components include the internal electronics, the handset, and the various plastic parts.
Plastic parts
- 1 To produce the plastic parts like the base, handset casing, and push buttons, injection molding is typically done. In this process, pellets of plastic polymer are put into the hopper of an injection molding machine. They then pass through a hydraulically controlled screw and are melted. While the screw rotates, the melted plastic is moved through a nozzle and injected into a mold. Just prior to this injection, the two halves of a mold are brought together to form a cavity which matches the shape of the telephone part. While inside the mold, the plastic is held under pressure for a set amount of time and then allowed to cool. As it cools, it hardens and forms into the shape of the part. This mold is coated with chromium to create a shiny surface.
- 2 After a short while, the mold halves are opened and the part is ejected. The mold then closes again and the process begins again. At this point in process, many of the parts are manually inspected to ensure that no significantly damaged parts are used. If there are damaged parts, they are set aside to be remelted and reformed into new parts.
Internal electronics
- 3 The electronic components of the telephone are sophisticated and use the latest in electronic processing technology. The circuit board is produced the same way that boards are made for other types of electronic equipment. The process begins with a board made of non-conducting material that has the electronic configuration printed on it using a conducting material. This board is then passed through a series of machines that place the appropriate chips, diodes, capacitors and other electronic parts in the appropriate places. To prevent damage caused by dust, the process is completed in a specially cleaned room. When completed, it is sent to the next step for soldering.
- 4 To affix the electronic parts to the board, a wave soldering machine is used. Before being put into the machine, the board is washed to remove contaminants. Upon entering, the board is heated using infrared heat. The underside of the board is passed over a wave of molten solder and through capillary action, all of the necessary spots are filled. As the board is allowed to cool, the solder hardens and the pieces stay in place. This creates an electrical connection between the printed circuits and the components.
Assembly and Packaging
- 5 The individual parts are assembled both automatically and manually. The transmitter and receiver are put together by machines. These parts are then fed onto the main assembly line and inserted into the molded headset. Similarly, the internal electronics, including the touch-tone pad, are inserted into the main housing and attached with screws. The headset is then put on the phone base and the phone chord may also be put on.
- 6 After all of the phone pieces are assembled, the completed phones are put in final packaging. Typically, they are wrapped in plastic and put in boxes. A packaging material such as polystyrene is also included to protect the device from damage during shipping. An owner's manual or other literature is included and the box is sealed with tape. The boxes are stacked on pallets, shipped to distributors and finally, customers.
Quality Control
To ensure the quality of each telephone, visual and electrical inspections are done throughout the entire production process and most flaws are detected. Additionally, the each completed phone is tested to make sure it works. Often these tests are done under different environmental conditions such as excessive heat and humidity to simulate the extremes that are experienced in a real life setting. Plastic parts are given torture tests to ensure they will still function even after a level of consumer abuse. For example, the numbers on a touch tone pad are put under a rubber-finger that taps the buttons enough times that it equals forty years of dialing. Since many of the parts that make up the telephone are produced by subcontractors, telephone manufacturers rely heavily on these suppliers for good quality. To ensure consistent manufacturing, most telephone makers set quality specifications for individual parts that the suppliers must meet.
The Future
Telephone technology is improving rapidly. In the future, cordless phones will be designed to be smaller and lighter. They will have wider transmission and better reception ranges. The sound quality will also be improved. Other technologies that integrate the phone with computers and cable television will be commonplace. Dialing systems will also be improved. In a recent demonstration, one company showed a technology that accepted voice command to dial a phone number.
XXX . V Mobile Phones
Mobile phones are very useful for people with low vision and there are plenty of models to choose from with different levels of functionality.
If a mobile is primarily required for making phone calls, a simple phone with basic functions is ideal. It should have large, high contrast keys and display, loud ring tones and emergency call functions. Some phones can be personalised to have just a few pre-programmed numbers that are accessible at the push of a single button.
If a mobile is primarily required for making phone calls, a simple phone with basic functions is ideal. It should have large, high contrast keys and display, loud ring tones and emergency call functions. Some phones can be personalised to have just a few pre-programmed numbers that are accessible at the push of a single button.
If a mobile phone is needed for additional functions, select a model with screen reader software. The phone will then speak all of the information on the screen, including contacts, caller information and text messages. It should also have a screen enlargement function, to increase the font size on the screen, and a high contrast display panel for easier reading.
Smart Phones, such as the Apple iPhones, have a broad range of features including functions to support people with low vision. Some of these features are magnification and speech accessibility for voice navigation commands.In addition to the usual tools of phone, email and web accessibility, smart phones can provide GPS navigation and support applications such as talking books.
XXX . V0 TELEVISION AND RADIO
Television and Radio
When it comes to watching television, there are many large screen options available, along with universal remote controls that have large buttons. When choosing a television, consider an LED TV, which offers more vibrant colours and sharper contrast.
Some televisions now come with built-in voice guidance. Voice guidance speaks aloud onscreen information using text-to-speech technology and enables blind and visually impaired viewers to control their TV by voice, for example, changing channels and searching for programs.
Digital radios provide very clear sound output. There is now a wide range to choose from including those with large print, large buttons and high colour contrast.
Radio for the Print Handicapped (RPH) provides a radio reading service for people who cannot see, handle or understand printed material. Programming includes readings from daily newspapers and articles from magazines as well as book readings and extracts from a variety of publications on topics such as health, music, art, entertainment, science.
Audio Technology Audio books Audio books, or talking books, can be sourced from a range of providers including low vision agencies, council libraries and audio book websites. The content can be played on a range of devices including standard CD players, MP3 devices and tablet computers. Some newspapers are also available in audio format. Navigator audio book The Navigator is a ‘low tech’ portable audio book device. Digital files of books or newspapers are loaded on to the Navigator from a computer. It can hold an average of five books in its memory (approximately thirty hours of listening). The Navigator is available from Macular Disease Foundation Australia and also in selected libraries around Australia and some low vision organisations. Macular Disease Foundation Australia’s Navigator Home Access Program allows users to access audio books and newspapers from a website and download them onto the Navigator audio book unit. The download process requires some computer experience so some people with low vision may require assistance from family or friends. Once loaded, the Navigator is very easy to use and, as it is light and portable, it can be used at home or out and about
XXX . V00 Computers and Software
XXX . V000 Electronic Magnifiers
Some televisions now come with built-in voice guidance. Voice guidance speaks aloud onscreen information using text-to-speech technology and enables blind and visually impaired viewers to control their TV by voice, for example, changing channels and searching for programs.
Digital radios provide very clear sound output. There is now a wide range to choose from including those with large print, large buttons and high colour contrast.
Radio for the Print Handicapped (RPH) provides a radio reading service for people who cannot see, handle or understand printed material. Programming includes readings from daily newspapers and articles from magazines as well as book readings and extracts from a variety of publications on topics such as health, music, art, entertainment, science.
Audio Technology Audio books Audio books, or talking books, can be sourced from a range of providers including low vision agencies, council libraries and audio book websites. The content can be played on a range of devices including standard CD players, MP3 devices and tablet computers. Some newspapers are also available in audio format. Navigator audio book The Navigator is a ‘low tech’ portable audio book device. Digital files of books or newspapers are loaded on to the Navigator from a computer. It can hold an average of five books in its memory (approximately thirty hours of listening). The Navigator is available from Macular Disease Foundation Australia and also in selected libraries around Australia and some low vision organisations. Macular Disease Foundation Australia’s Navigator Home Access Program allows users to access audio books and newspapers from a website and download them onto the Navigator audio book unit. The download process requires some computer experience so some people with low vision may require assistance from family or friends. Once loaded, the Navigator is very easy to use and, as it is light and portable, it can be used at home or out and about
XXX . V00 Computers and Software
Technology has changed the way we undertake many tasks, from accessing information to driving a car.
Even if it hasn’t been part of your education or life experience so far, it is possible to learn the skills necessary to make use of computer technology and software. Talk to one of the many low vision service providers about computer training programs and typing courses. Local Computer Pals clubs for seniors, which offer a fun and supportive environment, may also be suitable for learning computer skills. Technical Aid to the Disabled (TAD) can help to provide affordable computer packages for people with a disability.
Another excellent resource is Media Access Australia (MAA). MAA is a not-for-profit organisation devoted to increasing access to media for people with disabilities. Their website contains information on assistive technology.
Additionally, starting with both magnification and a reader may simplify the transition to speech only if vision deteriorates further.
Some of the popular screen magnifiers and readers are Guide, Zoom Text and Jaws.
Guide
Guide is a good program to use for those who are not familiar with using the computer but want to learn to send and receive emails and browse the Iinternet. It is specifically designed for beginners, with an easy to use menu, built in magnification, colour contrast and text-to-speech capability.
Zoom Text
Zoom Text is suitable for people using Windows operating systems who need to magnify images on the computer. It has magnification capabilities up to 60x, as well as enhanced mouse pointers and cursors. Zoom Text also has the ability to change background colours to increase contrast, and an optional text-to-speech output.
JAWS
JAWS works with computers to provide access to operating systems, software applications and the internet. JAWS has a text-to-speech application that vocalises everything on screen in an orderly way. It also supports a large number of Braille applications.
Microsoft Windows has a built-in narrator, and has third party software support, which allows for greater access.
Apple Mac has built-in full-screen magnification, a voice over feature that converts text-to-speech, voice command capability and high-contrast settings.
Non-Visual Desktop Access – or NVDA - provides Windows users with a free text-to-speech program.
Web Anywhere is a text-to-speech tool that integrates into the web browser in virtually any operating system, providing free basic voice access to the internet. The voice software can work on almost any computer with sound and will start almost immediately after download.
System Access to Go is an online screen reader, available from any Internet Explorer connected Windows Computer.
Even if it hasn’t been part of your education or life experience so far, it is possible to learn the skills necessary to make use of computer technology and software. Talk to one of the many low vision service providers about computer training programs and typing courses. Local Computer Pals clubs for seniors, which offer a fun and supportive environment, may also be suitable for learning computer skills. Technical Aid to the Disabled (TAD) can help to provide affordable computer packages for people with a disability.
Another excellent resource is Media Access Australia (MAA). MAA is a not-for-profit organisation devoted to increasing access to media for people with disabilities. Their website contains information on assistive technology.
Maximising vision using computer technology
There are many ways you can maximise remaining vision by using technology, including choosing a large screen to increase the viewing area and increasing the size of items displayed on the screen.
To make type easier to read, choose simple fonts without decorative curves, such as Arial or Calibri, and type in upper and lower case instead of all capitals. Add extra space between words and lines of text.
To make type easier to read, choose simple fonts without decorative curves, such as Arial or Calibri, and type in upper and lower case instead of all capitals. Add extra space between words and lines of text.
The following modifications will help you get the most from your computer:
- A large monitor to increase your viewing area
- A large print keyboard or large font keyboard stickers applied to the keys
- Software that increases the cursor size
- If the mouse or cursor is difficult to use, it may be easier to learn to touch type and use keyboard commands
- Enlarge the toolbar display
- Change the colour contrast
Computer technology for people with low vision
Electronic note takers
An electronic note taker is basically an adapted personal data service. Users can do the same tasks that a typical personal data device allows including: taking notes, reading email, diary functions, calculator, playing music, or digital books and data transfer to or from computers. Because the electronic note takers are adapted for persons who are blind or vision impaired, they have built in speech output.Tablets and small personal computers
Netbooks, ultrabooks, and tablet personal computers are essentially just small computers. They are highly portable which means that those with low vision can readily access low vision technology when out and about.Software options for people with low vision
Screen magnification software
Screen magnification software increases the size of the image displayed on the screen. This means only a portion of the original screen image can be seen at one time. The mouse or keyboard can then be used to move the magnified window to view other parts of the original screen image.Screen reading software
Screen reading software is also available to translate text into speech and is designed for people with very little usable vision. They may also be built in to some websites such as this one – by pressing the ‘Listen’ button at the top of the screen, the text will be read aloud.Screen magnifier and reader
At times, a program with a screen magnifier AND speech reader may help. For example, Type Echo - hearing text as it is typed can be useful for new or slow typists. Listening to long documents or web pages may be less tiring than reading with a screen magnifier.Additionally, starting with both magnification and a reader may simplify the transition to speech only if vision deteriorates further.
| Function | ||
| Program | Screen magnifier | Screen reader |
| Guide Zoom Text MAGic | ✔ | ✔ |
| Magnifying Glass Pro Mouse Magnifier Utility Lightning | ✔ | |
| JAWS Windows-Eyes Thunder Dragon Dictate | ✔ | |
Popular screen magnifiers and readers
Some of the popular screen magnifiers and readers are Guide, Zoom Text and Jaws.Guide
Guide is a good program to use for those who are not familiar with using the computer but want to learn to send and receive emails and browse the Iinternet. It is specifically designed for beginners, with an easy to use menu, built in magnification, colour contrast and text-to-speech capability.
Zoom Text
Zoom Text is suitable for people using Windows operating systems who need to magnify images on the computer. It has magnification capabilities up to 60x, as well as enhanced mouse pointers and cursors. Zoom Text also has the ability to change background colours to increase contrast, and an optional text-to-speech output.
JAWS
JAWS works with computers to provide access to operating systems, software applications and the internet. JAWS has a text-to-speech application that vocalises everything on screen in an orderly way. It also supports a large number of Braille applications.
Free software options
There are a number of free software options to choose from, provided by suppliers that include Microsoft, Apple and Linux.Microsoft Windows has a built-in narrator, and has third party software support, which allows for greater access.
Apple Mac has built-in full-screen magnification, a voice over feature that converts text-to-speech, voice command capability and high-contrast settings.
Non-Visual Desktop Access – or NVDA - provides Windows users with a free text-to-speech program.
Web Anywhere is a text-to-speech tool that integrates into the web browser in virtually any operating system, providing free basic voice access to the internet. The voice software can work on almost any computer with sound and will start almost immediately after download.
System Access to Go is an online screen reader, available from any Internet Explorer connected Windows Computer.
Web browsers
Whether you use Windows or Mac, you access the Internet through a web browser. There are several web browsers available, the most popular being Internet Explorer, Mozilla Firefox and Chrome. Each contains a variety of features which can help people with low vision who rely on the use of a keyboard or need to make a webpage easier to see.XXX . V000 Electronic Magnifiers
Hand held electronic magnification
Hand held electronic magnification provides distortion-free viewing as well as the ability to change background and foreground colours for glare reduction. They are useful for people who have progressed from hand held optical devices, for identifying objects and reading. Hand held electronic magnifiers require a medium amount of training with little follow up support. Products available are the Compact+, Compact Mini and Looky, which all operate with standard or rechargeable batteries. Pricing ranges from approximately $500 to $1,100.
The Farview Hand Held Electronic Distance magnifier greatly assists mobility by capturing and magnifying distant images. This small rectangular unit is also used in education for capturing information on whiteboards. Of value is the ability to scan an entire page then scroll around the page once the image is captured.
Hand held electronic distance magnifiers
Students and active seniors find that hand held electronic distance magnifiers, which capture and magnify distant images, greatly assist mobility. They can be used to capture information on whiteboards and to scan whole pages of information then scroll around the page once the information is captured.
Hand held electronic distance magnifiers cost around $4,000.
Training is important and a low level of support will be required. The unit is powered by rechargeable batteries.
Computer connectable – optical camera
The ClearNote and ClearNote Plus are optical cameras on a flexible arm that connect to the computer. They offer high flexibility for near and distance viewing and very high magnification levels. Images can be captured and stored on the PC then magnified and enhanced for display on the computer screen. These products are useful for students and seniors with a PC, for study, craft and distance viewing.
The ClearNote and ClearNote Plus require batteries and a USB. Pricing is around $4,000 to $5,000 and, while training is required support requirements after training are low.
Computer connectable - digital cameras
Computer connectable - digital cameras enable text to be captured quickly, and converted to large print and speech on a PC. Words are highlighted as they are spoken. Speech files can also be saved and used on MP3 type devices. Currently available are the Pearl, Zoom-Ex and Zoom-Twix computer connectable digital cameras, which are useful for students and seniors with a PC.
Pricing ranges widely from $2,000 - $5,000 for these units, which run on mains power and require a USB. A high degree of training is required with moderate ongoing support.
Desktop electronic magnifiers
Desktop electronic magnifiers are by far the most commonly used aid for reading, writing, and handicrafts. The source material is simply inserted onto a flat bed scanner and the image projects onto the screen. There are various options available for screen sizes, reading modes, non-reflective screens and high definition. ClearView and ViVA are two desktop electronic magnifers, which greatly enhance independent living skills. They are suitable for anyone with low vision, run on mains power and require minimal training. Prices range from $3,000 to $6,000.
The desktop electronic magnifier PC offers the same basic design and functionality as regular desktop electronic magnifiers. However it has the additional flexibility of connecting to a PC. Users can choose to use the magnifier’s screen, the PC screen, or both. Split screen options facilitate study and employment opportunities.
The ClearView PC (include image) is suitable for anyone with low vision, for home use, study or in the office. It requires mains power, needs little training and is priced at around $4,000.
Magnification Software (include image) for PC by ZoomText, MAGic, and iZoom provide useful access to computing and Internet for all low vision users. This software requires a high level of training with moderate levels of ongoing support.
XXX . V0000 Mobile security
Mobile security, or more specifically mobile device security, has become increasingly important in mobile computing. Of particular concern is the security of personal and business information now stored on smartphones.
More and more users and businesses use smartphones to communicate, but also to plan and organize their users' work and also private life. Within companies, these technologies are causing profound changes in the organization of information systems and therefore they have become the source of new risks. Indeed, smartphones collect and compile an increasing amount of sensitive information to which access must be controlled to protect the privacy of the user and the intellectual property of the company.
All smartphones, as computers, are preferred targets of attacks. These attacks exploit weaknesses inherent in smartphones that can come from the communication mode—like Short Message Service (SMS, aka text messaging), Multimedia Messaging Service (MMS), wifi, Bluetooth and GSM, the de facto global standard for mobile communications. There are also exploits that target software vulnerabilities in the browser or operating system. And some malicious software relies on the weak knowledge of an average user. According to a finding by McAfee in 2008, 11.6% users had heard of someone else being affected by mobile malware, but only 2.1% had personal experience on such problem.[1] However, this number is expected to grow.
Security countermeasures are being developed and applied to smartphones, from security in different layers of software to the dissemination of information to end users. There are good practices to be observed at all levels, from design to use, through the development of operating systems, software layers, and downloadable apps.
XXX . V00000 Challenges of mobile security
Threats
A smartphone user is exposed to various threats when they use their phone. In just the last two-quarters of 2012, the number of unique mobile threats grew by 261%, according to ABI Research.[2] These threats can disrupt the operation of the smartphone, and transmit or modify user data. So applications must guarantee privacy and integrity of the information they handle. In addition, since some apps could themselves be malware, their functionality and activities should be limited (for example, restricting the apps from accessing location information via GPS, blocking access to the user's address book, preventing the transmission of data on the network, sending SMS messages that are billed to the user, etc.).
There are three prime targets for attackers:[3]
- Data: smartphones are devices for data management, and may contain sensitive data like credit card numbers, authentication information, private information, activity logs (calendar, call logs);
- Identity: smartphones are highly customizable, so the device or its contents can easily be associated with a specific person. For example, every mobile device can transmit information related to the owner of the mobile phone contract, and an attacker may want to steal the identity of the owner of a smartphone to commit other offenses;
- Availability: attacking a smartphone can limit access to it and deprive the owner of its use.
There are a number of threats to mobile devices, including annoyance, stealing money, invading privacy, propagation, and malicious tools.[4]
- Botnets: attackers infect multiple machines with malware that victims generally acquire via e-mail attachments or from compromised applications or websites. The malware then gives hackers remote control of "zombie" devices, which can then be instructed to perform harmful acts.[4]
- Malicious applications: hackers upload malicious programs or games to third-party smartphone application marketplaces. The programs steal personal information and open backdoor communication channels to install additional applications and cause other problems.[4]
- Malicious links on social networks: an effective way to spread malware where hackers can place Trojans, spyware, and backdoors.[4]
- Spyware: hackers use this to hijack phones, allowing them to hear calls, see text messages and e-mails as well as track someone's location through GPS updates.[4]
The source of these attacks are the same actors found in the non-mobile computing space:[3]
- Professionals, whether commercial or military, who focus on the three targets mentioned above. They steal sensitive data from the general public, as well as undertake industrial espionage. They will also use the identity of those attacked to achieve other attacks;
- Thieves who want to gain income through data or identities they have stolen. The thieves will attack many people to increase their potential income;
- Black hat hackers who specifically attack availability.[5] Their goal is to develop viruses, and cause damage to the device.[6] In some cases, hackers have an interest in stealing data on devices.
- Grey hat hackers who reveal vulnerabilities.[7] Their goal is to expose vulnerabilities of the device.[8] Grey hat hackers do not intend on damaging the device or stealing data.
Consequences
When a smartphone is infected by an attacker, the attacker can attempt several things:
- The attacker can manipulate the smartphone as a zombie machine, that is to say, a machine with which the attacker can communicate and send commands which will be used to send unsolicited messages (spam) via sms or email;[10]
- The attacker can easily force the smartphone to make phone calls. For example, one can use the API (library that contains the basic functions not present in the smartphone) PhoneMakeCall by Microsoft, which collects telephone numbers from any source such as yellow pages, and then call them.[10] But the attacker can also use this method to call paid services, resulting in a charge to the owner of the smartphone. It is also very dangerous because the smartphone could call emergency services and thus disrupt those services;[10]
- A compromised smartphone can record conversations between the user and others and send them to a third party.[10] This can cause user privacy and industrial security problems;
- An attacker can also steal a user's identity, usurp their identity (with a copy of the user's sim card or even the telephone itself), and thus impersonate the owner. This raises security concerns in countries where smartphones can be used to place orders, view bank accounts or are used as an identity card;[10]
- The attacker can reduce the utility of the smartphone, by discharging the battery.[11] For example, they can launch an application that will run continuously on the smartphone processor, requiring a lot of energy and draining the battery. One factor that distinguishes mobile computing from traditional desktop PCs is their limited performance. Frank Stajano and Ross Anderson first described this form of attack, calling it an attack of "battery exhaustion" or "sleep deprivation torture";[12]
- The attacker can prevent the operation and/or be starting of the smartphone by making it unusable.[13] This attack can either delete the boot scripts, resulting in a phone without a functioning OS, or modify certain files to make it unusable (e.g. a script that launches at startup that forces the smartphone to restart) or even embed a startup application that would empty the battery;[12]
- The attacker can remove the personal (photos, music, videos, etc.) or professional data (contacts, calendars, notes) of the user.[13]
Attacks based on communication
Attack based on SMS and MMS
Some attacks derive from flaws in the management of SMS and MMS.
Some mobile phone models have problems in managing binary SMS messages. It is possible, by sending an ill-formed block, to cause the phone to restart, leading to the denial of service attacks. If a user with a Siemens S55 received a text message containing a Chinese character, it would lead to a denial of service.[14] In another case, while the standard requires that the maximum size of a Nokia Mail address is 32 characters, some Nokia phones did not verify this standard, so if a user enters an email address over 32 characters, that leads to complete dysfunction of the e-mail handler and puts it out of commission. This attack is called "curse of silence". A study on the safety of the SMS infrastructure revealed that SMS messages sent from the Internet can be used to perform a distributed denial of service (DDoS) attack against the mobile telecommunications infrastructure of a big city. The attack exploits the delays in the delivery of messages to overload the network.[15]
Another potential attack could begin with a phone that sends an MMS to other phones, with an attachment. This attachment is infected with a virus. Upon receipt of the MMS, the user can choose to open the attachment. If it is opened, the phone is infected, and the virus sends an MMS with an infected attachment to all the contacts in the address book. There is a real-world example of this attack: the virus Commwarrior[13] uses the address book and sends MMS messages including an infected file to recipients. A user installs the software, as received via MMS message. Then, the virus began to send messages to recipients taken from the address book.
Attacks based on communication networks
Attacks based on the GSM networks
The attacker may try to break the encryption of the mobile network. The GSM network encryption algorithms belong to the family of algorithms called A5. Due to the policy of security through obscurity it has not been possible to openly test the robustness of these algorithms. There were originally two variants of the algorithm: A5/1 and A5/2 (stream ciphers), where the former was designed to be relatively strong, and the latter was designed to be weak on purpose to allow easy cryptanalysis and eavesdropping. ETSI forced some countries (typically outside Europe) to use A5/2. Since the encryption algorithm was made public, it was proved it was possible to break the encryption: A5/2 could be broken on the fly, and A5/1 in about 6 hours .[16] In July 2007, the 3GPP approved a change request to prohibit the implementation of A5/2 in any new mobile phones, which means that it has been decommissioned and is no longer implemented in mobile phones. Stronger public algorithms have been added to the GSM standard, the A5/3 and A5/4 (Block ciphers), otherwise known as KASUMI or UEA1[17] published by the ETSI. If the network does not support A5/1, or any other A5 algorithm implemented by the phone, then the base station can specify A5/0 which is the null-algorithm, whereby the radio traffic is sent unencrypted. Even in case mobile phones are able to use 3G or 4G which have much stronger encryption than 2G GSM, the base station can downgrade the radio communication to 2G GSM and specify A5/0 (no encryption) .[18] This is the basis for eavesdropping attacks on mobile radio networks using a fake base station commonly called an IMSI catcher.
In addition, tracing of mobile terminals is difficult since each time the mobile terminal is accessing or being accessed by the network, a new temporary identity (TMSI) is allocated to the mobile terminal. The TSMI is used as the identity of the mobile terminal the next time it accesses the network. The TMSI is sent to the mobile terminal in encrypted messages.
Once the encryption algorithm of GSM is broken, the attacker can intercept all unencrypted communications made by the victim's smartphone.
Attacks based on Wi-Fi Wi-Fi § Network_security
An attacker can try to eavesdrop on Wi-Fi communications to derive information (e.g. username, password). This type of attack is not unique to smartphones, but they are very vulnerable to these attacks because very often the Wi-Fi is the only means of communication they have to access the internet. The security of wireless networks (WLAN) is thus an important subject. Initially, wireless networks were secured by WEP keys. The weakness of WEP is a short encryption key which is the same for all connected clients. In addition, several reductions in the search space of the keys have been found by researchers. Now, most wireless networks are protected by the WPA security protocol. WPA is based on the "Temporal Key Integrity Protocol (TKIP)" which was designed to allow migration from WEP to WPA on the equipment already deployed. The major improvements in security are the dynamic encryption keys. For small networks, the WPA is a "pre-shared key" which is based on a shared key. Encryption can be vulnerable if the length of the shared key is short. With limited opportunities for input (i.e. only the numeric keypad), mobile phone users might define short encryption keys that contain only numbers. This increases the likelihood that an attacker succeeds with a brute-force attack. The successor to WPA, called WPA2, is supposed to be safe enough to withstand a brute force attack.
As with GSM, if the attacker succeeds in breaking the identification key, it will be possible to attack not only the phone but also the entire network it is connected to.
Many smartphones for wireless LANs remember they are already connected, and this mechanism prevents the user from having to re-identify with each connection. However, an attacker could create a WIFI access point twin with the same parameters and characteristics as the real network. Using the fact that some smartphones remember the networks, they could confuse the two networks and connect to the network of the attacker who can intercept data if it does not transmit its data in encrypted form.
Lasco is a worm that initially infects a remote device using the SIS file format.[22] SIS file format (Software Installation Script) is a script file that can be executed by the system without user interaction. The smartphone thus believes the file to come from a trusted source and downloads it, infecting the machine.
Principle of Bluetooth-based attacks Bluesnarfing and Bluebugging
Security issues related to Bluetooth on mobile devices have been studied and have shown numerous problems on different phones. One easy to exploit vulnerability: unregistered services do not require authentication, and vulnerable applications have a virtual serial port used to control the phone. An attacker only needed to connect to the port to take full control of the device.[23] Another example: a phone must be within reach and Bluetooth in discovery mode. The attacker sends a file via Bluetooth. If the recipient accepts, a virus is transmitted. For example: Cabir is a worm that spreads via Bluetooth connection.[13] The worm searches for nearby phones with Bluetooth in discoverable mode and sends itself to the target device. The user must accept the incoming file and install the program. After installing, the worm infects the machine.
Attacks based on vulnerabilities in software applications
Other attacks are based on flaws in the OS or applications on the phone.
Web browser Browser security
The mobile web browser is an emerging attack vector for mobile devices. Just as common Web browsers, mobile web browsers are extended from pure web navigation with widgets and plug-ins, or are completely native mobile browsers.
Jailbreaking the iPhone with firmware 1.1.1 was based entirely on vulnerabilities on the web browser.[24] As a result, the exploitation of the vulnerability described here underlines the importance of the Web browser as an attack vector for mobile devices. In this case, there was a vulnerability based on a stack-based buffer overflow in a library used by the web browser (Libtiff).
A vulnerability in the web browser for Android was discovered in October 2008. As the iPhone vulnerability above, it was due to an obsolete and vulnerable library. A significant difference with the iPhone vulnerability was Android's sandboxing architecture which limited the effects of this vulnerability to the Web browser process.
Smartphones are also victims of classic piracy related to the web: phishing, malicious websites, software that run in the background, etc. The big difference is that smartphones do not yet have strong antivirus software available.
Operating system Operating_system § Security
Sometimes it is possible to overcome the security safeguards by modifying the operating system itself. As real-world examples, this section covers the manipulation of firmware and malicious signature certificates. These attacks are difficult.
In 2004, vulnerabilities in virtual machines running on certain devices were revealed. It was possible to bypass the bytecode verifier and access the native underlying operating system The results of this research were not published in detail. The firmware security of Nokia's Symbian Platform Security Architecture (PSA) is based on a central configuration file called SWIPolicy. In 2008 it was possible to manipulate the Nokia firmware before it is installed, and in fact in some downloadable versions of it, this file was human readable, so it was possible to modify and change the image of the firmware.[25] This vulnerability has been solved by an update from Nokia.
In theory smartphones have an advantage over hard drives since the OS files are in ROM, and cannot be changed by malware. However, in some systems it was possible to circumvent this: in the Symbian OS it was possible to overwrite a file with a file of the same name.[25] On the Windows OS, it was possible to change a pointer from a general configuration file to an editable file.
When an application is installed, the signing of this application is verified by a series of certificates. One can create a valid signature without using a valid certificate and add it to the list.[26] In the Symbian OS all certificates are in the directory: c:\resource\swicertstore\dat. With firmware changes explained above it is very easy to insert a seemingly valid but malicious certificate.
Attacks based on hardware vulnerabilities
Electromagnetic Waveforms
In 2015, researchers at the French government agency Agence nationale de la sécurité des systèmes d'information (ANSSI) demonstrated the capability to trigger the voice interface of certain smartphones remotely by using "specific electromagnetic waveforms".[27] The exploit took advantage of antenna-properties of headphone wires while plugged into the audio-output jacks of the vulnerable smartphones and effectively spoofed audio input to inject commands via the audio interface.[27]
Juice Jacking Juice_jacking
Juice Jacking is a physical or hardware vulnerability specific to mobile platforms. Utilizing the dual purpose of the USB charge port, many devices have been susceptible to having data exfiltrated from, or malware installed onto a mobile device by utilizing malicious charging kiosks set up in public places or hidden in normal charge adapters.
Jail-breaking and rooting
Jail-breaking is also a physical access vulnerability, in which mobile device users initiate to hack into the devices to unlock it, and exploit weaknesses in the operating system. Mobile device users take control of their own device by jail-breaking it, and customize the interface by installing applications, change system settings that are not allowed on the devices. Thus, allowing to tweak the mobile devices operating systems processes, run programs in the background, thus devices are being expose to variety of malicious attack that can lead to compromise important private data .
Password cracking
In 2010, researcher from the University of Pennsylvania investigated the possibility of cracking a device's password through a smudge attack (literally imaging the finger smudges on the screen to discern the user's password).[29] The researchers were able to discern the device password up to 68% of the time under certain conditions.[29] Outsiders may perform over-the-shoulder on victims, such as watching specific keystrokes or pattern gestures, to unlock device password or passcode.
Malicious software (malware) Malware
As smartphones are a permanent point of access to the internet (mostly on), they can be compromised as easily as computers with malware. A malware is a computer program that aims to harm the system in which it resides. Trojans, worms and viruses are all considered malware. A Trojan is a program that is on the smartphone and allows external users to connect discreetly. A worm is a program that reproduces on multiple computers across a network. A virus is malicious software designed to spread to other computers by inserting itself into legitimate programs and running programs in parallel. However, it must be said that the malware are far less numerous and important to smartphones as they are to computers.
[30]
Nonetheless, recent studies show that the evolution of malware in smartphones have rocketed in the last few years posing a threat to analysis and detection.[31]
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