Title: Experiences with Ad Hoc and P2P Networking
1Experiences with Ad Hoc and P2P Networking
- Dr. Milena Radenkovic
- PhD, Computer Science, Nottingham, UK
- Dipl Ing., MSc, Electrical and Electronic
Engineering, Nis, Serbia - BA in Computer Science, American University in
Bulgaria
2Research Overview
- Research interests centre on self-organised
network architectures that support interactive
multiuser applications in unstable and
heterogeneous environments - Particular concern is with the design and
deployment of novel mobile ad-hoc, delay tolerant
network and P2P architectures for data store and
query and routing protocols - Multiple applications in location based pervasive
gaming, wearable medical and veterinary
applications and mass environmental monitoring - A Novel Routing Protocol for Large Scale
Disconnected (PI, EPSRC), - Developing Advanced Collaborative Environments
for Life Science Community (PI, EPSRC) - Participate (CI, EPSRC),
- myGrid (CI, EPSRC)
- IPERG, (WPLead, EU), MIAS (WPLead, EPSRC)
3Supporting Collaborative Applications(Games)
(past current projects PhD)
- Collaborative Virtual Environments (CVEs),
Inhabited TV, Mixed Reality Environments, (e.g.
games and TV shows) - Merging physical and virtual worlds in mobile
wireless systems - Extreme end system and network heterogeneity
convergence of media - Large number of simultaneous users and
simultaneous live A/V streams but also
heterogeneous sensor data - PhD concerned with the challenges for scaleable
network multimedia architectures
4Remote sensing with e-Science
- Focus on science in the field
- Scientists remote from the grid
- Access to grid facilities when connections are
limited or occasional - Environmental e-Science
- In Antarctic
- Ice thickness, light intensity, water saltiness,
GPS, weather info - and in the city
- CO and pedestrian movement
- Remote Medical Monitoring
- Supplement medical information
- respiratory, heart, blood, temperature
- with physical information
- Movement
- Location
- Posture
5Distributed Partial Mixing (DPM) Approach
(International Patent (WO 02/17579 A1) 2002, ACM
Multimedia 2002, IEEE Telsiks 2001, MIT Press
PRESENCE, 2004)
Application driven
End system resource driven
Network driven
- Support for
- the most natural and spontaneous verbal
communication - packet loss management and delays
- maximal flexibility for audio tailoring at the
end users - heterogeneous networks and machines
- efficient distribution of audio/video streams in
the network - congestion control adaptability, inter-protocol
fairness
6Self-organised, ad-hoc, fully distributed DPM
(ACM VRST 2002, MIT Press PRESENCE 2004)
C7
- Unmanaged deployment domain frequent and severe
fluctuations in link quality - DPM placed in end systems
- On-demand DPM initiation
- Distributed collaborative controlling process
nodes continuously evaluate contribution of each
node - Adaptive topology congruent with the underlying
physical network
C8
Congested link
C6
C4
C5
DPM
New group
C3
DPM
C2
C1
New group
7PARTICIPATE (CI)
- Continues to explore convergence in pervasive,
online and broadcast media to create new kinds
of mass-participatory events in which the public
contributes to and accesses contextual content. - Aims to support participants understanding of
individual impact on the environment AND to
support change. - Develop an architecture that integrates diverse
media, devices and networks - My Focus
- How to support mass-scale sensor data capture and
query in challenged environments - Investigate novel overlays that can help build
applications on the top of mobile, unstable and
unreliable environments - How do we support the querying of partially
defined data (i.e. range search queries)?
8(No Transcript)
9ScienceScope sensor and data logger, with screen
shots from the GeoMobSens application (collecting
environmental audio and carbon monoxide
levels).
10Collected sound levels visualised on Google Earth
11Carbon monoxide levels from the collected data
12Mass-scale sensor data capture, route and query
in challenged environments (ASWN 06, WONS 07,
ICN 08, ICN 09, WINET 09)
- Novel locality preserving DHT overlays optimised
for mobility and disconnections - New policies for forwarding and replication that
utilise heterogeneity - Opportunistic utilization of locally available
resources - Novel DHT substrates (Layer 3 routing) optimised
for mobility and disconnections - Utilises self organised caching and mobility to
improve dissemination of data (e.g. compared to
other substrates) - Novel mass Scale DTN Routing
- Novel hybrid MANET and DTN routing protocols with
DHT naming scheme - Use Bluetooth logs to indentify contact
opportunities and mobility patterns in order to
discover groups and profiles of users to design
optimal forwarding and routing policies
13A Possible Deployment Scenario
PSN
MANET
DHT overlay across publicly owned infrastructure
Mobile Phone
Game Logic
ContextPhone
DTN
P2P Node
Game Logic
WiFi
147
15Time zones of Friend, Acquaintance and Stranger
Contact Clusters (digital footprint 1)
Node with the majority of Friend contacts
considered more reliable and good to be a data
mule or gateway
16Time zones of Friend, Acquaintance and Stranger
Contact Clusters (digital footprint 2)
Node with the majority of Stranger contacts
suitable for data dissemination to a wide
community
17Cost Effective Mass Games in Unstable
Environments (WONS 2007)
- Hybrid Pastry
- Exploits locality and high knowledge about
neighbours - 3 types of nodes to account for heterogeneity
- Regular Clients (RCs)
- Super Clients (SCs)
- Application Servers (ASs)
- Hybrid Pastry outperforms Pastry in terms of SR
for average and low densities. Average delays are
not increased.
18DHT substrate to address disconnections(ASWN
2006, IEEE Multimedia 2008)
- State
- Contains data related to animals health and
location - Is identified by animals id and timestamp
- Every node stores its own state and up to k
states from other nodes
- Results
- Success ratio twice as high as EKTAs in the case
of increased mobility and disconnections while
not increasing network overhead
19Delay Tolerant Mass Scale Cattle Monitoring(ICNS
2006, ICN 2007, ICN 2008, WiNET 2009)
- Identify realistic requirements
- Strong demands for detecting oestrus, lameness,
animal diseases - Trails with bluetooth GPS, mobile phones, video
footage - Enable continuous and delay tolerant
multi-dimensional parameter monitoring - Utilises existing infrastructure but also works
in fully ad-hoc mode - Retention of data, in-situ and remote queries and
notifications - Increases fairness and decreases energy
utilization
20Energy Efficient Route Discovery(ICN 2007, ICN
2008, WINET 2009)
- Low data traffic but unstable path
- Save energy on path discovery (i.e. having more
stable paths) - Minimizing and balancing energy utilisation
- Adaptive control of transmitter power
- Passive Clustering with Delayed intelligence
(flood control) - Selecting routes with longest lifetime
- Least number of hops, Least number of
deteriorating links, Minimal total power - Delaying non urgent data exchanges waiting for
acquisition of a valid route to a target node
from overheard or forwarded packets - Using movement patterns
- less mobile gt more stable paths gt more forward
- faster animals gt better message carriers
- Significant energy saving compared to ESDSR, more
fair energy consumption and shorter delays
21myGrid(CI), (ICWI 2003, CCGRID 2003, GADA 2005,
SAG 2004, AHM 2005)
- Open Source Upper Middleware for Bioinformatics
- Developing high level services for data intensive
integration rather than computationally intensive
problems - Workflows, Provenance
- Semantic-based resource discovery and matching.
- My focus on the deployment perspective
- Personalised semantic driven notification service
- Semantic driven web portal and gateway
- Integration with WSRF
- P2P Access Grid
22Data at the centre
Workflows that could use this data
People who have registered an interest in this
data
Related Data
Provenance of the data
Ontologies describing data
23myGrid Services
Work bench
Taverna workflow environment
Talisman application
Portal
Gateway
Personalisation
Service and Workflow Discovery
myGrid Information Repository
Provenance mgt
Ontology Mgt
Event Notification
Metadata Mgt
Workflow enactment engine
Distributed Query Processor
Soaplab
Communication fabric
Bio Services
Text Extraction Service AMBIT
Bio Services
24myGrid deployment perspective
25Future research
- Infrastructure and protocols that support true
convergence of pervasive, online and broadcast
media on the global scale - Embrace radically heterogeneous networking
- Two end-systems should be able to communicate
even if they have nothing in common protocols,
address realms, semantics (Jon Crowcroft) - P2P, DTNs, PSNs but learn from Grids and WSs
- Proposals in preparation
- Trust, Reputation and support for security in
disconnected worlds - Self organized security in DTNs in collaboration
with Watson IBM - Aim to extend DTN security bundle with novel
flexible and fluid trust building, negotiation
and propagation mechanisms based on behavioral
modeling, anomalous behavior across
disconnections and non consensus asynchronous
partial trust claiming and resolving - Congestion Control and QoS in disconnected worlds
- Self organized congestion control in DTNs in
collaboration with Watson IBM - Source driven and receiver driven feedback and
rate adaptation - Application domains
- Medical, Military, Environmental, Social
26Observed Movement Patterns
27Realistic Parameters
- Communication parameters
- Infrequent in-situ queries (field trials)
- Delivering data to sinks every 2-4 hours (field
trials) - Low amount of data (literature)
- Movement patterns
- Typical speed 0.6 m/s (literature)
- Rarely faster than 0.8 m/s (field trials)
- Stocking density on pastures 2-7 animals/ha
(literature) - Drinking, eating and milking patterns (field
trials) - Movement patterns difficult to predict (field
trials)
28Simulation Results
- Beacons, sinks. selecting routes with
min.transmitter power requirements considerably
decrease energy usage of mobile nodes during data
transfers compared to ESDSR - At the cost of the increasing the delays of
delivering data to sinks and energy usage of
sinks
29Simulation Results
- Energy consumption of the new approach up to 40
lower than in the old approach - New approach offers more fair energy consumption
and shorter delays
30This time its personal
- my services
- my favourite services
- my opinion of those services
- my workflows
- my data
- my notes
- my queries
- my logs of what I did
- The events I care about
31Notification Personalisation
- Dynamic creation of personal data sets in mIR
- Personal views over repositories.
- Personalisation of workflows.
- Personal notification
- Annotation of datasets and workflows.
- Personalised service registries what I think
the service does, which services can GSK
employees use
- Has PDB changed since I last ran this?
- Has the record I derived my record from changed?
- Has the workflow I adapted my workflow from
changed? - Did the provenance record change?
- Has a service I am using right now gone? Has an
equivalent one sprung up? - Event notification service.
32Simulation Results (Hybrid Pastry)
33Simulation Results (DHT substrate)
- Passive caching
- Always increases success ratio (as expected)
- Decreases network overhead in sparse topologies
(better results than expected) - Increases scalability
- Proactive caching
- Appropriate in case of very high mobility
- Anticipated long periods of limited or no query
traffic. - Does not increase success ratio as much as
expected - Literature informed simulation parameters (no. of
nodes, velocities)