The Homework project has examined redesign of existing home network infrastructures to better support the needs and requirements of actual home users. Integrating results from several ethnographic studies, we have designed and built a home networking platform providing detailed per-flow measurement and management capabilities supporting several novel management interfaces. This demo specifically shows these new visualization and control interfaces, and describes the broader benefits of taking an integrated view of the networking infrastructure, realised through our router's augmented measurement and control APIs.



Aspects of this work have been published: the Homework Database in Internet Management (IM) 2011 and implications of the ethnographic results are to appear at the SIGCOMM W-MUST workshop 2011. Separate, more detailed expositions of the interface elements and system performance and implications are currently under submission at other venues. A partial code release is already available and we anticipate fuller public beta release by Q4 2011

Bedwell, B.

Glover, K.

Koliousis, A.

Lodge, T.

Moore, A.

Mortier, R.

Rodden, T.

Rotsos, C.

Sventek, J.

English

Enlighten: Publications

Enlighten – Research publications by members of the University of Glasgow 
http://eprints.gla.ac.uk 
 
 
 
 
 
 
 
Mortier, R., Bedwell, B., Glover, K., Lodge, T., Rodden, T., Rotsos, C., 
Moore, A., Koliousis, A. , and Sventek, J. (2011) Supporting novel home 
network management interfaces with Openflow and NOX. In: SIGCOMM 
2011, 15-19 Aug 2011, Toronto, Ontario, Canada. 
 
http://eprints.gla.ac.uk/69030/ 
 
 
Deposited on: 7th September 2012 
 
 
Supporting Novel Home Network Management Interfaces
with Openflow and NOX
Richard Mortier,
Ben Bedwell,
Kevin Glover, Tom Lodge,
Tom Rodden
University of Nottingham, UK
first.last@nottingham.ac.uk
Charalampos Rotsos,
Andrew W. Moore
University of Cambridge, UK
first.last@cl.cam.ac.uk
Alexandros Koliousis,
Joseph Sventek
University of Glasgow, UK
first.last@glasgow.ac.uk
ABSTRACT
The Homework project1 has examined redesign of existing
home network infrastructures to better support the needs
and requirements of actual home users. Integrating results
from several ethnographic studies, we have designed and
built a home networking platform providing detailed per-
flow measurement and management capabilities supporting
several novel management interfaces. This demo specifically
shows these new visualization and control interfaces (§1),
and describes the broader benefits of taking an integrated
view of the networking infrastructure, realised through our
router’s augmented measurement and control APIs (§2).
Aspects of this work have been published: the Homework
Database in Internet Management (IM) 2011 [3] and im-
plications of the ethnographic results are to appear at the
SIGCOMM W-MUST workshop 2011 [2]. Separate, more
detailed expositions of the interface elements and system
performance and implications are currently under submis-
sion at other venues. A partial code release is already avail-
able2 and we anticipate fuller public beta release by Q4 2011.
Categories and Subject Descriptors:
C.2.6 [Computer-Communication Networks]: Routers
General Terms:
Management, Design, Security, Human Factors
Keywords: Home networks; Network management; DHCP;
NOX; OpenFlow
1. USER INTERFACES
The first two interfaces make use of the hwdb stream-
ing database for visualization. The first, Figure 1, runs on
an iPhone/iTouch device and simply displays the per-device
per-protocol bandwidth consumption. This allows users to
focus on how their devices and their applications, to the ex-
tent permitted by the imperfect application–protocol map-
ping, are using the network.
The second, Figure 2, is a custom hardware interface based
on the Arduino platform3 enabling awareness of the network
as a whole rather than specific devices. Via its LEDs, It
1http://www.homenetworks.ac.uk/
2https://github.com/homework/
3http://www.arduino.cc/
Copyright is held by the author/owner(s).
SIGCOMM’11, August 15–19, 2011, Toronto, Ontario, Canada.
ACM 978-1-4503-0797-0/11/08.
Figure 1: Per-device bandwidth consumption. 
 
information plane and updated in real-time, allowing users 
to view the impact of their actions on the network as they 
change their behavior (e.g., by pausing applications).  
 
 
Physical Probe 
Out final ma ifestation takes the f rm of th  physical arti-
fact shown in Figure 6, providing bo h an ambient aware-
ness of network activity as a whole (in contrast to the more 
precise view provided by graphical displays) and the ability 
to uncover hidden aspects of the network’s topology. The 
artifact contains a series of RGB LEDs that respond to key 
network characteristics. The current artifact supports three 
distinct modes: 
• Mode 1. Wireless signal strength from the artifact to the 
hub is mapped to the number of lit LEDs, allowing the 
user to carry the artifact around to expose areas of high 
or low signal strength in the home.  
• Mode 2. The current total bandwidth usage of the net-
work as a proportion of peak usage observed in the last 
day is mapped to animation of the LEDs, causing lights 
to appear to move more quickly across the face of the ar-
tifact if more bandwidth is used. 
• Mode 3. DHCP leases granted and revoked are signaled 
by a series of flashes in either green or blue respectively, 
while high proportions of packet retries for any machine 
on the network are signaled by a series of red flashes. 
 
The latter two modes are intended to act as situated ambient 
display of the underlying network. The first mode seeks to 
allow people to use the artifact to uncover the wireless to-
pology of the house. As users move the device through the 
home, the received signal strength (RSSI) for the artifact is 
reflected by the measurement plane and mapped to the pro-
portion of LEDs lit, showing the signal strength to this part 
of the home from the router’s viewpoint. 
One of our interests is how these different manifestations of 
the network might be used in tandem. Our infrastructure 
has allowed these different displays to connect to the same 
measurement plane and be dynamically updated from the 
active database.  
CONTROLLING THE INFRASTRUCTURE  
Our router’s measurement infrastructure is complemented 
by a set of control mechanisms enabling interactive man-
agement of the network. As with our measurement ap-
proach, we seek to provide management through the infra-
structure with minimal presumptions as to the type of ma-
chine that will be connected to the network. Our control 
infrastructure treats the Homework Router as an OpenFlow 
device using the Open vSwitch and NOX implementations. 
OpenFlow, Open vSwitch & NOX 
OpenFlow is a switching standard developed by the Stan-
ford Clean Slate Networking program [7]. It provides an 
open protocol that enables distributed control of the flow 
tables contained within Ethernet switches in a network. An 
OpenFlow switch has three parts: a datapath, a secure 
channel connecting to a controller, and the OpenFlow pro-
tocol used by the controller to talk to the switch. 
Each OpenFlow datapath contains a set of physical ports, 
plus a flow table and a set of actions associated with each 
flow entry. Flows are defined in terms of the input datapath 
and selected values of packet header fields. There are four 
basic types of action, ranging from simply dropping or 
forwarding the packet, to forwarding it to the controller for 
further processing, to forwarding it through the switch’s 
normal processing pipeline. Packets can be modified as 
they are forwarded. 
  
Figure 5. Bandwidth consumption per machine 
(left-hand side) and usage per protocol for ʻTomʼs 
Mac Airʼ (right-hand side). 
  
  
Figure 6. The network artifact. 
 Figure 2: Network artefact as physical interface.
displays one of (i) wireless signal strength (RSSI) based on
number lit; (ii) current total bandwidth use mapped to the
speed of animation across the device; and (iii) DHCP lease
grant ac ivity indica ed by the colour of flas es.
The next two interfaces demonstrate two control mech-
anisms available in our platform. The first, Figure 3, is a
simple contr l interfac that exercises the cont ol API to
manage DHCP allocations, accessed via a si uated display
in the home. This allows non-expert users to detect, interro-
gate and supply metadata for devices requesting access, and
to control the DHCP server on a case-by-case basis by drag-
ging the device’s tab into the appropriate permitted/denied
category.
The final interface, Figure 4, integrates physical media-
tion of control into a simple visual policy language. When
the user plugs a USB storage device with appropriate file-
system layout into the router, it enables specific devices to
464
Figure 3: Simple control interface.
Figure 4: Novel interactive policy interface.
connect to the network as well as limiting access to spec-
ified web-hosted services, e.g., Facebook. By selecting ap-
propriate options for each panel in the cartoon, non-expert
users can implement simple policies such as “the kids can
only use Facebook on weekdays after they’ve finished their
homework.” This is mapped to per-device network and DNS
access restrictions which are only lifted once a suitably re-
sponsible adult inserts the appropriate USB storage key.
2. TECHNICAL DETAILS
Our platform takes the form of a small form-factor PC
acting as the home router, exposing various APIs used by
satellite interrogation and control devices. Providing those
APIs, our software sits atop a standard Linux Ubuntu dis-
tribution running Open vSwitch4 and NOX,5 depicted in
Figure 5 with our code shown as the shaded components.
The Homework Database, hwdb, provides measurement
support as an active ephemeral stream database which stores
ephemeral events into a fixed size memory buffer. It links
events into tables and supports queries via a CQL [1] vari-
ant able to express temporal and relational operations on
data. The database supports a simple UDP-based RPC in-
terface enabling applications to subscribe to query results,
persisting output as desired. Tables used are Flows, period-
ically observed active five-tuples; Links, link-layer informa-
tion, e.g., MAC address and received signal strength (RSSI);
and Leases, mapping Ethernet to IP address.
The control API NOX module provides a simple REST-
ful web interface to the router, invoked to exercise control
over connected devices: by the Linux udev subsystem when
a suitably formatted USB storage device is inserted; and di-
rectly by the various graphical control interfaces. The con-
4http://openvswitch.org/
5http://noxrepo.org/
ovsdb-­‐
server
dns
wlan0
openvswitch_mod
...
eth0
nox
hwdb
kernel
userspace
ovs-­‐vswitchd
data
control
logging
upstream
ISPlocal	  ethernet,
wired	  or	  wireless
bridge
dp0
udev	  usb
monitor
dhcp
control	  API
Figure 5: Software architecture of the Homework
home router.
trol API configures the behaviour of our DHCP server and
DNS proxy NOX modules. The first manages DHCP allo-
cations to ensure that all traffic flows are visible to software
running on the router, avoiding direct Ethernet-layer com-
munication between devices. The second intercepts outgo-
ing DNS requests, performing reverse lookups on flows not
matching previously requested names, to ensure that up-
stream communication is only allowed between permitted
devices and sites.
ACKNOWLEDGEMENTS
The research on which this paper is based was funded by
the RCUK supported Horizon Hub, EP/G065802/1, and
EPSRC Wired and Wireless Intelligent Networked Systems
Initiative “Homework”, EP/F064276/1.
3. REFERENCES
[1] A. Arasu, S. Babu, and J. Widom. The CQL continuous
query language: semantic foundations and query
execution. The VLDB Journal, 15:121–142, June 2006.
[2] P. Brundell, A. Crabtree, R. Mortier, T. Rodden,
P. Tennent, and P. Tolmie. The network from above
and below. In Proc. ACM SIGCOMM Workshop on
Measurements Up the STack (W-MUST), Toronto,
Canada, Aug. 2011. To appear.
[3] J. Sventek, A. Koliousis, O. Sharma, N. Dulay,
D. Pediatitakis, M. Sloman, T. Rodden, T. Lodge,
B. Bedwell, K. Glover, and R. Mortier. An information
plane architecture supporting home network
management. In Proc. IFIP/IEEE International
Symposium on Integrated Network Management (IM),
Dublin, Ireland, May 2011.
465


Supporting novel home network management interfaces with Openflow and NOX

http://eprints.gla.ac.uk/69030/1/69030.pdf

Supporting novel home network management interfaces with Openflow and NOX

Abstract

Similar works

Full text

Available Versions

Enlighten: Publications