Sight

Vision Impairment

Being registered blind or vision impaired does not mean that the student is unable to see. While you will encounter students that have no sight. For many It does mean their sight is sufficiently impaired that they will require considerable support. Different nations use differing legal terms regarding vision impairment. Such as legally blind or visually impaired, this section of the site covers the most common accommodations for anyone with notable sight loss.

Like many disabilities - there is no one solution fits all. However, many solutions described in this site will support many of the students you may encounter.

Stop!

Before you rush ahead and read on - please stop and think. Before you have read the content and believe that you have all the answers (which you won't). Please do take the time to speak with the student - their supporters and anyone who may have taught them in the past.

Often the vision impaired are the experts. Not you the teacher - this site aims to offer you the tools to start the conversation and have a little back information at your disposal.

The Impact of Vision Impairment

Vision impairment, also known as visual impairment, vision loss or commonly blindness, is the decreased ability to see beyond the scope that is fixable by glasses. Typically, the term blindness is used for complete or nearly complete vision loss. Definitions and terminology varies according to national health legislature in each nation. While there is considerable common ground, it may be worth checking what your nation defines in terms of vision loss and blindness. Vision impairment may cause people difficulties with normal daily activities such as driving, reading, socialising and walking.

The following is a summary from Wikipedia, (extracted late 2018):

  • The most common causes of vision impairment globally are uncorrected refractive errors (43%), cataracts (33%), and glaucoma (2%).

  • The World Health Organisation (WHO) estimates that 80% of vision impairment is either preventable or curable with treatment.

  • As of 2015 there were 940 million people with some degree of vision loss. 246 million had low vision and 39 million were blind.

The above figures cover the entire global population, while many of us endure sight loss related to advanced age. The number of people of encounter sight loss or vision impairment during their educational or working years is not insignificant.

Graphics

All computer displayed images require written (text based) descriptions. They must be written from the perspective of anyone with sight loss. This means that image or icon/element location (which is important for anyone with sight) is often irrelevant, positions such as left, right, top bottom are meaningless. For example, with networking diagrams - interconnections are more important than the diagrammatic position of a router.

They do not care if it is to the left!

Nor do they care if it is over to the right!

All descriptions must be done from a top down perspective, ideally present an overview then dive into the details. The information must be divided into logical blocks - such as focusing on each router as a separate block of information. Vision impaired students - typically perceive networks in a list format.

NetAcad provide descriptions for their images and are continually working on improving the descriptive content. However, there is room for descriptive improvements within their curriculum. Your students can switch on each description within the NetAcad content by pressing the transcript ‘speech bubble’ icon/button. This is accessible to screen readers and is suitably labelled.

The challenge is that many descriptions on offer are considered to be verbose and written from a sighted perspective

Example

The following image represents reasonable practice ... for anyone using a screen reader. The alternative (alt) screen reader text is also in the paragraph after the image. So that sighted readers can appreciate what is required.

The hidden alternative text is as follows:

This image represents a network with four devices. There are two personal computers and two switches. They are all connected. PC 0 is connected by a straight cable to Switch 0 - PC 0 uses port F a 0, the cable connected to port F a 0 slash 1 on Switch 0. Switch 0 is connected via a crossover cable to Switch 1. This is via port F a 0 slash 2 on Switch 0 and port F a 0 slash 1 on Switch 1. Switch 1 is connected to PC 1 via a straight cable. This is on port F a 0 slash 2 on Switch 1 and port F a 0 on PC 1. A connections are up and active - this is shown by a green circle on each end of each cable.

There are many writing styles for descriptive text. There is no 'exact' right way - however, we acknowledge there are many that are wrong.

Remember : it is top to bottom, left or right have no meaning. Try to describe your image, in a top down sequenced list format.

Note: did you see how we unpacked the port and device descriptions.

Video

Over time, since inception of NetAcad, Cisco have reduced the video content within their courses. However, there remains some invaluable video items. Which present different challenges. Many of these videos are typically ignored by vision impaired students.

Anyone with vision impairment requires a transcript. While they can (often) hear the dialogue - they need to know what is happening in the background. Subtitles also known as closed captions - offered on many media formats for many films and other visual content, also exists. While often used by the hearing impaired - some versions include additional information (such as where, what, who and what they are doing) for the viewer.

The quality of transcripts and subtitles is variable. You have to treat a video as if it has to be fully described for hearing and vision loss. Including both full dialogue and especially activity. The longer the video the greater the work commitment.

As a teacher - you have to decide how critical the video content is for your vision impaired student. In terms of their likelihood to require this additional information to pass the course.

Video Example

Below, is a short promotional video from Cisco. It runs for 1 minute and 7 seconds. It has excellent subtitling and is very accessible. It comes with a transcript (below) and you can watch it on both YouTube or this page.

Video Transcript

On the main site, you can see the full transcript running in a separate pane to the right (depending on screen size) - if you activate this option. The full text (copyright of Cisco) is as follows:

  1. 00:00 [Music]

  2. 00:04 Libbie global is the largest TV and

  3. 00:07 broadband company in the world we have

  4. 00:09 about 22 million customers across Europe

  5. 00:11 using our video and broadband services

  6. 00:14 so specifically what we're using is

  7. 00:17 Cisco's unified contact center

  8. 00:19 enterprise product there is of course

  9. 00:21 the element of the platform the

  10. 00:23 capabilities but there's another aspect

  11. 00:25 it's also the professional services that

  12. 00:27 are provided by Cisco I'm a services

  13. 00:30 perspective we looked around in the

  14. 00:31 market about you know looking at

  15. 00:33 partners that could potentially give us

  16. 00:35 the services that were required and

  17. 00:37 Cisco came to the forefront of that they

  18. 00:41 have been exceeding our expectation it's

  19. 00:44 been a pleasure working with these guys

  20. 00:45 very professional always open to

  21. 00:48 actually take on something outside of

  22. 00:51 their envelope and actually I think

  23. 00:53 that's also one of the key elements that

  24. 00:56 we've seen that made this program - its

  25. 00:58 accessories

  26. 00:59 [Music]

As you can read, there is no reference to any of the visual information in the background. Taking the first 20 seconds, you can adapt the transcript with:

  1. 00:00 [Music]

  2. Scenes of a large office environment

  3. 00:04 Libbie global is the largest TV and

  4. Middle aged white male sitting beside boardroom table - Captioned as Brian Matulin VP of Transformation Delivery - Liberty Global

  5. 00:07 broadband company in the world we have

  6. 00:09 about 22 million customers across Europe

  7. Woman walking through security barrier

  8. 00:11 using our video and broadband services

  9. 00:14 so specifically what we're using is

  10. Close up talking head of White Male (Brian Matulin) from earlier scene

  11. 00:17 Cisco's unified contact center

  12. 00:19 enterprise product there is of course

  13. Scene change to two white men in distance looking at screen

We have emboldened the text for emphasis. As is clear, information has been missed - including who is doing the talking.

Did you notice the typo! It isn't ours, this is copied from the full transcript. Unfortunately these are commonplace.

Tactile Adaptations

Both the Royal National College for the Blind and Curtin University (in Perth, Western Australia) have worked on the creation of teaching artefacts that students can use as representations of diagrams. Instead of having to work hard to create audio descriptions of every network diagram. They use 3D printed or foam cut outs of all of the standard icons and cable types.

As soon as any diagram is encountered in the curriculum, a lab exercise or on Packet Tracer. The teaching team member, learning support or in some cases one of the more able students. Creates a tactile copy of the network seen in the diagram.

Another commonplace example, is the teaching of Binary, IP addressing and Subnetworking via pin boards. Below is a shot of Iain (Instructor at Curtin University) and Leanne (Instructor at Royal National College for the Blind). Each working on the pin board in the centre of the image.

This is easy to create - pins can be raw plugs (used in DIY), the pins can be measured and corresponding holes drilled into most plywoods. As many of you are experienced teachers - we are sure that you may have already recognised that these adaptations can also be used for all manner of other students. Often younger students enjoy tactile learning. Also, with so many struggling with IP addressing and binary - the use of a peg board may make the difference

two people in a room, with a binary wooden pin board
a pin board, with 8 times 4 sets of pins and wooden dowel pins

Tactile Tools

Grahame Allen and Leanne Moore from the Royal National College for the Blind, based in Hereford, United Kingdom. Have been working on a range of tactile networking affordances. Taking the diagrams out of NetAcad into the hands (literally) of the vision impaired students.

Below is a simple example, demonstrating waveforms. With physical affordances (think velcro, lego, etc) you can recreate a multitude of conceptual networking diagrams.

Grahame showing a tactile sine wave - this was accomplished by taking some coated copper wire and shaping it to a normal sine.

Three examples of 'wire frame' waves, on the left (for the sighted) is a square, then a sine and to the right an example of signal noise.

Screen Reader

NVDA and Jaws are the two ‘recommended’ readers (there are others, however these two have been found to be the most consistent). The NetAcad content is not fully optimised for screen readers. While there have been some recent improvements from NetAcad, there remains a number of challenges that must be overcome before a student can fully engage with the NetAcad experience and the course content.

You will discover this works for individuals with low vision as well as others with cognitive requirements (such as Dyslexia). Also, some individuals with physical impairments use screen readers in concert with their adaptive devices.

Each screen reader has to be optimised for the student, their impairment and the software/website it is attempting to access. In principle - the simpler the site format, the easier (it should be) to read. Screen readers either output as spoken audio or as braille.

With NetAcad - you must consider three navigational domains:

  • The outer NetAcad wrapper with the top level resource menus and sections such as i'm learning (this is known as LifeRay).

  • The underlying Canvas site for each course each student is enrolled within

  • Course content - which is linked to by each Canvas course you have created

It is worth noting that each course, once created has a unique URL on Netacad - share this with your students and this can offer a number of fast routes into the learning material. Saving at least the top layer of navigation.

Everything is about guiding the student to the relevant point - the screen reader will read everything - each menu, submenu and image. However, once you get the student to the content. The navigation experience becomes linear and relatively straight forward.

It is worth creating a Module 0 in Canvas, which you can always import/export and give students shortcuts and essential navigational guidance. The + (plus) in the top right of the modules section of each course allows you to accomplish this. Also, different browsers and operating system versions will have an effect on the screen reader. Where the navigation works better or for that matter worse. Sadly this means that it is a case of trial and error for each system - each course and each student. Once a student is settled into using their environment it does become easier.

Command Line Challenges

The same screen reader requirements, applies for the command line environment. This works for the shell (command prompt) in a host operating system as well as a router/switch terminal session via TeraTerm, Putty or any other freely available tool. Most screen readers, once focused on the terminal window will read the output with little difficulty.

Provided by the Vision Impairment team at Curtin University and voiced by Joshua Gilchrist. Below is a demonstration of the NVDA screen reader - interacting with the Cisco IOS command line. For anyone hearing impaired and reading this, NVDA reads out every command, letter and option.

It takes a moment to become used to the chatter - this has been slowed down for the 'sight able'. Individuals with vision impairment can cope with a considerably faster chatter rate.

Screen Format.

As you may recall from the introduction - vision impairment does not mean that you cannot see. It does clearly mean that sight is challenging. Many of us require a slightly larger font and clearer text - depending on our glasses prescription. However, for individuals with vision impairments you are not considering a slightly larger font.

Most of the NetAcad content does not work well with ctrl + '+' or command + '+' as this enlarges the entire content light box out of scope of the browser window. NetAcad do recommend that you use a screen magnifier, which is available on all operating systems in different formats.

The host operating system can be configured with different user profiles. Some suited for low vision and different retinal conditions. You may have screen zoom, invert and colour theme options that suit the student you are working with.

In addition the same applies to cursor control and the general environment. A larger cursor is often very helpful, especially on smaller laptop screens. It is worth exploring the accessibility features of each operating system you use.

  1. For Windows - take a look at Ease of Access.

  2. For Mac's - take a look at Accessibility.

  3. For Linux - while distros will vary, consider installing Orca.

Environment!

Over time, anyone with a vision impairment will learn their way around your classroom. However you have to be continually mindful of obstructions and seemingly minor changes. A moved table means nothing to most of us. However when someone with a vision impairment collides into it - on route to the router rack. We are sure they will vocally express their feelings regarding this new obstacle.

Not everyone with a vision impairment can read Braille, however - this does not mean that you cannot create tactile clues for vision impaired students. For example Grahame a vision impaired instructor at the Royal National College for the Blind in the UK. Uses clipped cable ties on the end of cables to denote which are straight, crossover and class made rollover. It's simple, one tie, two ties and three ties.

Raised stickers - especially high visibility colours work well. Remember, most individuals with vision impairment can see, albeit not very well. Your vision impaired student will memorise location, interfaces and the different technologies. So long as you are consistent, especially during the early stages they will adapt. Allow them to take their time to find their own way. You do not need to overcompensate, they can independently cable and configure routers.

Solutions!

For all disabilities - solutions come through discovery and development. We will add ideas, suggestions and solutions accumulated over time from those that know (you, and the community of NetAcad Instructors).

In terms of known solutions you can:

  • Create tactile network diagrams

  • Offer physical affordances - making modifications to cables and equipment

  • Offer comprehensive image descriptions

  • Offer comprehensive video transcripts.

  • Adapt screen readers

  • Create peg boards for binary (and addressing).

  • Adjust the operating system environment and local vision settings including magnification (zoom) and colour scheme.

Summary

For any vision impaired disabled student in a practical computing situation, you must consider both the environment and what adaptations required. Often, modest changes to the way you work and the resources you offer, will make a considerable difference to the individual.