Talk slides from Ubicomp 2011, Beijing, 20th September 2011 (Session 4 - Near and Far). Based on the paper: Reflections on the Long-term Use of an Experimental Digital Signage System by Sarah Clinch, Nigel Davies, Adrian Friday, Christos Efstratiou. Paper abstract: In this paper we reflect on our long-term experiences of developing, deploying and supporting an experimental digital signage system. Existing public display systems almost always feature a single point of control that is responsible for scheduling content for presentation on the network and provide sophisticated mechanisms for controlling play-out timing and relative ordering. Our experiences suggest that such complex feature-sets are unnecessary in many cases and may be counter productive in signage systems. We describe an alternative, simpler paradigm for encouraging widespread use of signage systems based on shared ‘content channels’ between content providers and display owners. Our system has been in continuous use for approximately 3 years. We reflect and draw lessons from how our user community has adopted and used the resulting public display network. We believe that these reflections will be of benefit to future developers of ubiquitous display networks.

1. Reflections on the Long-
term Use of an Experimental
Public Display System
Sarah Clinch1, Nigel Davies1, Adrian Friday1 and
Christos Efstratiou2
1Lancaster University, 2Cambridge University, UK.
Tuesday, 20 September 11

2. We reflect on use of e-Channels:
a system for enabling the shared use of networked
situated displays by trusted user groups
e-Campus begins [1] e-Channels in everyday use 30 displays,
81 users,
2005
2008 2011 33 groups,
3,700 pieces
[1] Public ubiquitous computing systems: Lessons from the e-campus display deployments. IEEE Pervasive Computing, 5 (3). pp. 40-47. ISSN 1536-1268 of content
Tuesday, 20 September 11

3. should this really
be our decision?
Woah!
we need to design something that scales
better...
Problem: our approval of content was a bottleneck
Need to give users ownership of displays
Design goals: simplicity & stimulate ‘a network effect’
Tuesday, 20 September 11

4. content is arranged into ‘channels’
Display
Owner
e-Channels
by users (in known groups)
Role 2
channel channel
subscriptions properties, Channels
Web UI subscriptions Scheduler
channel
properties
schedule [2]
content
Role 1 file system
changes Displays
Content
Provider
media
files
file system
dropbox
[2] Storz, Oliver and Friday, Adrian and Davies, Nigel (2006) Supporting content scheduling on situated public displays. Computers & Graphics, 30 (5). pp. 681-691
Tuesday, 20 September 11

5. User experience video
The content provider sees this...
Tuesday, 20 September 11

6. User experience video
The display owner sees this...
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7. Questions we answer
1. How did the e-Channels system get
used - are channels a useful abstraction?
2. Do users generate content to share or
are they selfish? i.e. is there a network
effect?
3. What content do they put into the
system, how is it characterised?
4. Does the system get abused, or do we
retain control?
Tuesday, 20 September 11

8. Q1: Channels are used,
flexibly
CHANNEL_ACTIVATE CHANNEL_ADD
CHANNEL_DELETE CHANNEL_SUSPEND
90
A range of channel related
60
practices
# channel events
Group content and ‘suspend’
30
used during updates
Rarely deleted just
0
suspended
Arts
Business
Careers
Chap
Dep E
Dep P
Faculty 1
Faculty 2
L. Tech.
PR
Res 1
Res 2
Res 3
Res 7
St. Exp.
St. Recruit.
St. Services
St. Union
Theatre
Volunt.
Tuesday, 20 September 11

9. 1 channel,
frequent content
little content, lots
of subscriptions
engagement stops,
with staff change
Tuesday, 20 September 11

10. Q2: Sharing
We do our
They'll
never share
ade
20
own thing
15 To our
surprise, 53%
We do both!
# channels
10
of channels are
‘shared
channels’
5
0
available to the
network
Res 1
Chap
Dep E
Estates
Faculty 1
Business
Volunt.
PR
Arts
St. Services
St. Union
St. Recruit
Shared
Just our Private
public channel
Tuesday, 20 September 11

11. Q3: Content life
Is short (7-10 days) -
23% news, 16% forthcoming events
Or long (~120 days)
11% building projects, 9% services
More content is
added than
removed!
Tuesday, 20 September 11

12. Q3: Context & Validity
Unsupported
5.3%
Web pages
4.1%
Content rarely tightly bound to
Stream
location, but often audience
Video 0.3%
7.1% 24% had no obvious time
constraints
8% had a validity of one day; 8%
< 1 week; 12% a month; 21% 2-3
Images
83.2% months, and 12% a validity of 1
year+
Tuesday, 20 September 11

13. Q4: Trust, Moderation
& Abuse
• e-Channels took per-item moderation from
us to trusted user groups, devolving control
• Only 2 abuses reported:
• decontextualisation (video with sound
during an exam)
• situated-ness (a particular message a
college dean worried would be
interpreted as theirs)
Tuesday, 20 September 11

14. Gaming the System
• We found duplicate
content across
channels - but also
within a channel!
• Also sneaky ‘static-
video-slides’
• Deliberate practice to
gain air time - shows
understanding
Tuesday, 20 September 11

15. Take home
• Reflected on how e-Channels has been
adopted & found it is effective in sharing
networked displays with many stakeholders
• Trusted content providers devolve
moderation and keep control & do generate
content for sharing
• Display owners find a balance between
monopoly and shared content
• Users continue to underestimate the cost &
effort of producing content
Tuesday, 20 September 11

16. Please see the paper for fuller explanations
of the data and the unexpurgated design
lessons
Questions
?
Adrian Friday
adrian@comp.lancs.ac.uk
http://www.comp.lancs.ac.uk/~adrian
http://pd-net.org
Partially funded by the PD-NET project: http://pd-net.org
PD-NET is a FET-Open project funded from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 244011
Tuesday, 20 September 11