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Streaming Media in the Classroom Jacob E. Larsen
Emerging Technology Specialist, Information Technology Services
March 2014
Executive Summary Streaming of digital media such as audio, video, and photos to a classroom provides a simple and easy
way of integrating these sources into a course. To facilitate this, instructors may use a streaming media
device which is capable of playing locally or remotely stored media files. Testing conducted by the
Information Technology Services unit found that the Roku 3 and Western Digital TV Live streaming
media devices may be good options for adding streaming media capabilities to an ISU classroom. It was
also found that the Plex Media Server is a viable solution for hosting and serving these media files to
either device.
Introduction Over the past few years Iowa State University (ISU) Information Technology Services (ITS) has seen an
increase in faculty requests for media streaming capabilities in classrooms. Typically, users have
approached ITS with a desire to display digital video in their classrooms. This video would normally come
from one of three sources: Online, on the user’s own computer, or on a USB flash drive. In order to
determine how ITS can best support these usage scenarios a review was conducted of four commercial
media streaming devices with a view to identifying the best option(s). This white paper contains the
results of this review together with an overview of the concept of media streaming. The review also
touches upon the various network, security, and usability issues associated with offering this capability
in classrooms. Lastly, device recommendations are provided.
Media Streaming Devices and Software Media streaming devices have been on the market for several years now as have different kinds of
media server software. However, before diving into a review of the devices and software it is useful to
gain an understanding of the different associated concepts.
Streaming Media
Streaming media is defined as “multimedia that is constantly received by and presented to an end-user
while being delivered by a provider…. A client media player can begin playing the data (such as a movie)
before the entire file has been transmitted” (Streaming Media, 2014, paras. 1-2). This can be compared
to other media systems that are inherently non-streaming, such as books, DVD movies and CD audio
(Streaming Media, 2014, para. 2).
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Movie and Audio Formats
Movies and audio that is stored digitally and streamed to various receiving devices come in a variety of
formats. An early and well-known audio format is MP3. Many different digital media formats exist for
movies and audio such as MPEG-2, used for DVDs, MPEG-4, used for online distribution of large videos,
and H.264, which is the format high-definition Blu-ray discs are encoded in (Multimedia Container
Formats, 2014, para. 5).
Another aspect of streaming video and audio concerns the ‘container formats’. These are represented
by the file extensions often referred to and seen appended at the end of files, such as the
aforementioned MPEG-1 or MPEG-2 Audio Layer III (MP3) (Wikipedia, 2014, para. 1), Flash Video (FLV),
Matroska (MKV), QuickTime File Format (MOV), and MPEG-4 (MP4) (Multimedia Container Formats,
2014, para. 5)
These formats are relevant because a streaming media player is only able to play certain built-in
formats. Thus, it is desirable that a player is able to handle as many formats as possible in order to
accommodate the various formats that users may wish to use. Alternatively, a file server must be used
that can read these various file formats and decode, or translate, them into a format that a player can
understand. For more on this, see the discussion of the Plex Media Server in the following section.
Media Server Software
Many users with extensive digital movie libraries like to use various kinds of software to categorize and
deliver them to their monitors or TV screens. One example of such a piece of software is Plex Media
Server which can be installed on a central computer or server and set up to deliver streaming audio and
video to streaming media receivers or devices. A big advantage of the Plex Media Server is that it can
transcode (change the format of) media before it is streamed in order to reduce bandwidth
requirements or for compatibility with the device being streamed to (Plex, 2014, para. 12).
Another example of media server software is the kind of capability that a Digital Living Network Alliance
(DLNA) compatible device has. DLNA server capability is built into the Windows operating system
through its home network file sharing options. A DLNA server may also be a dedicated server computer
set up to serve media to many computers at the same time. One advantage of DLNA servers is that
most consumer digital devices are able to connect to them and receive content. However, a
disadvantage is that they do not always support transcoding of the media. This may result in very large
files being streamed on the network in their original size, leading to network slow-downs and stuttering
or extensive buffering, lasting several minutes, when trying to view the media.
Considering that users who have digital video files on their computers or on removable media, such as
USB flash drives, will need a way of delivering these files to the streaming media devices a central
repository for this media would be a desirable option. It is not feasible or sustainable for instructors or
faculty to share files over the campus network from their own computers, whether on-campus or off-
campus. Furthermore, given the multitude of potential file formats that users might wish to play, it
makes sense to have a media server solution that can handle most available formats while being
securely connected to the classroom streaming media devices.
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In order for streaming media devices to play media from a streaming media server, they need to be
compatible. Different devices are able to connect to different media servers with the most common
ones being the Plex Media Server and those using the DLNA standard. Apple TV can only receive streams
from software or servers that use the Digital Audio Access Protocol (DAAP), such as iTunes.
Device Evaluation In order to try to decide which media streaming devices might work best in a variety of ISU classrooms
ITS researched popular home-user devices online. Based on online reviews, four devices were evaluated:
Roku 3, Apple TV (Gen. 3), Western Digital Live TV, and Google Chromecast. The devices were
subsequently evaluated according to the following criteria:
Ease of setup and classroom integration
Ease of use
Media format capabilities
Video server connectivity and playback
Device Recommendations While the four devices each excelled at different tasks and in different environments the Roku 3, in
conjunction with the Plex Media Server software, provided a winning combination. This setup allowed
for stutter-free playback of a wide variety of different media formats while providing easy setup and
linking between the Plex Media Server and the Roku 3 via its dedicated Plex channel. The Roku 3 also
had the best user interface, quick navigation, the best remote control and the greatest selection of free
internet radio and TV channels. It should also be noted that the Roku 3 has a USB port that allows users
to connect an external USB flash drive or hard drive and play some of the most common movie formats,
such as MPEG-4 and H.264. Lastly, even if a Plex Media Server is not available, the Roku 3 will stream
media from a DLNA server.
The Western Digital TV Live was the test runner-up due to a strong set of features that includes network
and USB playback of a multitude of formats (several more than the Roku 3), while providing a good user
interface. While the WD TV LIVE is able to connect to DLNA servers for playback of streaming media, this
protocol is susceptible to stuttering during playback of large, high-bitrate files. Consequently, the WD TV
Live is useful when it comes to supporting different file types locally, but falls a bit short in terms of
streaming media files from a server.
The Apple TV and Google Chromecast both serve different home user niches. However, they miss
several features that would make them well-suited to a large campus network. For example, the Apple
TV will only stream video from the internet, such as Netflix or YouTube, or from a networked Mac or PC
computer with an iTunes account. Considering that iTunes accounts are typically very personalized, this
is not ideal for use in an institutional networking setting with potentially hundreds of users. In addition,
its networking protocol, Bonjour, is designed for home networks and does not work well with large-scale
institutional networks such as ISU’s. This is a well-known problem that many IT professionals from public
and private institutions have petitioned Apple to fix, though so far without any luck (Faas, 2012).
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The Chromecast, on the other hand, is severely limited in its ability to play media that is streaming on
the local network, as opposed to from the internet. All content playback must be initiated from a
connected device, such as a smartphone, tablet or laptop. Only media which plays in the Chrome
Browser or on the Chromecast app for mobile devices will work. Furthermore, it is purely wireless,
which makes it more susceptible to influence from network connections compared to the other devices,
which can all connect via Ethernet.
It should also be noted that during classroom testing the Roku was not able to access the DLNA test
server running on a desktop computer in another building. Because of this, any DLNA servers on the ISU
network may need to be set up and connected to the Roku 3 by an IT networking professional.
Consequently, ITS recommends using a Roku 3 and the Plex Media Server. Alternatively, if the content to
be played is available on portable media, the WD TV Live device is an option. If this function is desired in
a general assignment classroom managed by FPM & ITS, contact ([email protected]) to request
installation.
Limitations The testing that was done on these streaming media devices was rigorous and tried to take into
consideration different user needs, operating environments, and a selection of different file formats.
However, it is very difficult to predict all possible scenarios. In addition, technology changes fast and the
devices reviewed may gain or lose features in future models. Consequently, users may wish to conduct
some testing with their chosen device in their actual teaching environment(s) before committing to a
solution. ITS is happy to help with this and is available for questions.
References and Resources Digital Living Network Alliance (2014). In Wikipedia. Retrieved from
http://en.wikipedia.org/wiki/Digital_Living_Network_Alliance.
Faas, R. (Aug. 6th, 2012). Education IT Pros Petition Apple To “Fix” Bonjour. Retrieved from
http://www.cultofmac.com/182919/education-it-pros-petition-apple-to-fix-
bonjour/#9u0UdlSDQw42TLLX.99.
Multimedia Container Formats (2014). In Wikipedia. Retrieved from
http://en.wikipedia.org/wiki/Digital_container_format#Multimedia_container_formats.
Plex (software), (2014). In Wikipedia. Retrieved from
http://en.wikipedia.org/wiki/Plex_%28software%29.
Plex Media Server (2014). Plex: Plex Media Server (version 0.9.818.290) [Software]. Available from
https://plex.tv/.
Streaming Media (2014). In Wikipedia. Retrieved from http://en.wikipedia.org/wiki/Streaming_media.