Talk @ Universität Zürich

1. Universität Zürich
Information-Centric Networking in
Mobile Networks
Torsten Braun, Universität Bern, Switzerland
braun@iam.unibe.ch, cds.unibe.ch

2. Torsten Braun: Information-Centric Networking in Mobile Networks
Overview
> Future Internet
> Information-Centric Networking (ICN)
— Content-Centric Networking
— Service-Centric Networking
— ICN and Cloud Computing
> ICN in Mobile / Wireless Networks
— Mobility
— Delay/Disruption-Tolerant and Opportunistic Networks
> Conclusions
Zürich, 22.02.2013 2

3. Torsten Braun: Information-Centric Networking in Mobile Networks
Future Internet
> The current Internet is based on principles
of the 1960s with the main purpose to
interconnect large computers.
> Today, Internet users are mainly interested
in retrieving content and accessing services
with increasing demand for mobility & security
> Increasing bandwidth demand due to
— (personalized) multimedia data streams
— Cloud computing and storage,
visualization on (mobile / high-resolution) end systems
— Huge amounts of data from measurements and scientific experiments
— Internet of Things, Internet of Services, …
> New approaches, e.g., Information-Centric Networking,
need more research, development, testing etc.
Zürich, 22.02.2013 3

4. Torsten Braun: Information-Centric Networking in Mobile Networks
Motivation for
Information-Centric Networking
> Today’s network traffic is dominated by information retrieval
rather than point-to-point communication between machines
or humans.
> Circuit communication model is not considered as appropriate
any more.
> Future communication architecture should focus on
information objects instead of nodes.
> Today, wires and memories solve complimentary aspects of
the same problem:
— Wires move information in space.
— Memories move information in time.
> Future communications architecture should unify both issues.
> Flash crowds are difficult to avoid in IP-based networks.
Zürich, 22.02.2013 4

5. Torsten Braun: Information-Centric Networking in Mobile Networks
Traditional Web Retrieval / Web Services
search engine /
service registry
user’s end system
web server /
web service
DNS server
Zürich, 22.02.2013 5

6. Torsten Braun: Information-Centric Networking in Mobile Networks
Key Principles and Functions of ICN
> Naming of content rather than hosts/interfaces
— Content independent of devices that store it
— Naming is location independent (receiver mobility support !)
> Receivers (subscribers) request content.
> Senders (publishers) advertise and deliver content.
> Receivers and senders do not have to be aware of each
other and are decoupled in time.
> Functions needed
— Name resolution to match subscriptions and publications
— Routing and path formation
— Forwarding content from publisher to subscriber
Pentikousis, K.; Chemouil, P.; Nichols, K.; Pavlou, G.; Massey, D.; "Information-centric networking",
IEEE Communications Magazine, vol.50, no.7, pp.22-25, July 2012
Zürich, 22.02.2013 6

7. Torsten Braun: Information-Centric Networking in Mobile Networks
Content Distribution with ICN
/unibe.ch/braun/lecture/os/20130219
1
2 3
4 5 6 7
Zürich, 22.02.2013 7

8. Torsten Braun: Information-Centric Networking in Mobile Networks
Naming Approaches
> Human-readable, hierarchical names
— supports aggregation
— needs coordination
— Example: CCN
> Flat (self-certifying) names
— Often based on hashing content name and/or owner’s public key
— Aggregation more difficult but more flexible.
— Example: PSI
Zürich, 22.02.2013 8

9. Torsten Braun: Information-Centric Networking in Mobile Networks
Name Resolution and Data Transport
> Decoupled
— Name resolution and data transport are independent of each
other, cf. DNS, with possibly different nodes for resolution and
data transport
— allows different, possibly already existing transport mechanisms,
also multi-path
— Example: PSI
> Coupled
— Nodes for both name resolution and data transport with inverse
data path compared to search path
— rather disruptive technology
— Local routing procedures advantageous in case of short link
disruptions
— Example: CCN
Zürich, 22.02.2013 9

10. Torsten Braun: Information-Centric Networking in Wireless/Mobile Networks
Publish/Subscribe Internetworking (PSI)
> Information producer publishes information item to rendezvous
system consisting of rendezvous nodes.
> Information consumer subscribes to information item.
> Rendezvous system
— matches announcements and subscriptions
— triggers delivery from information producer to information
consumer, e.g. using OpenFlow
> Various caching strategies: on-path, off-path, replication
publication path establishment
subscription
Medellin, October 5, 2012 10

11. Torsten Braun: Information-Centric Networking in Mobile Networks
Content-Centric Networking (CCN)
> Combination of content lookup and message routing
> Idea: describe the user’s interests in the message header,
but not where to get it.
> Messages (using XML encoding)
— Interest: content name, selector
— Data: content name, signature (info), data
> Hierarchical content names
— Example: /unibe.ch/braun/lecture/os/20130219
> Related Projects
— NDN = Named Data Networking, www.named-data.net
— CCNx = Open Source Core Software Project for
Content-Centric Networking, www.ccnx.org
Van Jacobson, Diana K. Smetters, James D. Thornton, Michael F. Plass, Nicholas H. Briggs, and Rebecca L. Braynard:
Networking named content, 5th international conference on Emerging networking experiments and technologies (CoNEXT '09).
ACM, New York, NY, USA, 1-12.
Zürich, 22.02.2013 11

12. Torsten Braun: Information-Centric Networking in Mobile Networks
IP Model
FIB
FIB: Forwarding Information Base
Zürich, 22.02.2013 12

13. Torsten Braun: Information-Centric Networking in Mobile Networks
Interest Message Processing in CCN
1. Longest prefix match on content name in Content Store:
returning data and discarding Interest
2. Pending Interest Table match:
adding request to PIT and discarding Interest
3. Forwarding Information Base match:
forwarding of Interest towards data
— FIB population by announcements of content availability
Zürich, 22.02.2013 13

14. Torsten Braun: Information-Centric Networking in Mobile Networks
Match in Content Store
CS FIB
Name Data
PIT
Name
CS: Content Store
FIB: Forwarding Information Base
PIT: Pending Interest Table
Zürich, 22.02.2013 14

15. Torsten Braun: Information-Centric Networking in Mobile Networks
Match in Forwarding Information Base
CS FIB
PIT
Name
Zürich, 22.02.2013 15

16. Torsten Braun: Information-Centric Networking in Mobile Networks
Match in Pending Interest Table
Name
CS FIB
PIT
x
Zürich, 22.02.2013 16

17. Torsten Braun: Information-Centric Networking in Mobile Networks
CCN Naming
> Hierarchical naming allowing aggregation
> Examples
— /unibe.ch/braun/lecture/os/20130219
— /unibe.ch/N10/R306/Projector
> Support for simple operations
— %C1.org.ccnx.frobnicate~1~37
— command in the namespace org.ccnx
— operation is frobnicate, which takes 1 and 37 as arguments
Zürich, 22.02.2013 17

18. Torsten Braun: Information-Centric Networking in Mobile Networks
CCN Routing
> Longest Prefix Match Routing (as in IP)
> FIB entries should be populated proactively for known content.
> Alternatively, searching for content, e.g., using flooding
Zürich, 22.02.2013 18

19. Torsten Braun: Information-Centric Networking in Mobile Networks
CCN Evaluation
> Advantages
— Automatic content distribution
— Minimization of latency: < 1 round-trip-time
— Minimization of bandwidth
— Local congestion control
— Built-in security
> Challenges
— Routing protocols
— Hierarchical naming
— Source mobility
— Services
Zürich, 22.02.2013 19

20. Torsten Braun: Information-Centric Networking in Mobile Networks
Service-Centric Networking (SCN)
> ICN/CCN is content-centric and encodes a few operations on content
as extensions of names.
> Proposal: Service-Centric Networking
— Extension of content-centric networking to support services,
possibly operating on content.
— Description of a service using content naming scheme,
e.g., /google.com/file-service
— Service request (response) in Interest (Data) message
> Services
— Infrastructure services, e.g., cloud computing services
— Client-oriented services, e.g., web services
— Continuous content retrieval and streaming services,
e.g., A/V conferencing, streaming
— Event services, e.g., exceeding sensor data thresholds or stocks data
— In-network services, e.g., aggregation and filtering of (sensor) data
Braun, T.; Hilt, V.; Hofmann, M.; Rimac, I.; Steiner, M.; Varvello, M.: Service-Centric Networking, 2011 IEEE
International Conference on Communications Workshops (ICC), pp.1-6, Kyoto, 5-9 June 2011
Zürich, 22.02.2013 20

21. Torsten Braun: Information-Centric Networking in Mobile Networks
Service-Centric Network
SCN network
SCN router
Service request/response
Zürich, 22.02.2013 21

22. Torsten Braun: Information-Centric Networking in Mobile Networks
Advantages of SCN
> No service lookup and service registry
> Caching of service data
> Extended caching of multimedia data (transcoding)
> Location-based services
> Optimized service selection
Zürich, 22.02.2013 22

23. Torsten Braun: Information-Centric Networking in Mobile Networks
Uniform Naming for Services (Functions)
and Content (Data)
> Services perform (data) processing and are represented by
functions to be invoked. Content stores for data.
> Service-centric networking should support both data and functions.
> Object-orientated programming paradigm integrates
both functions and data into objects.
Method calls among objects to invoke functions.
> Proposal: Object names for both services (functions) and content
(data), e.g.,
— /youtube.com/rendering
— /unibe.ch/braun/lecture/os/20130219
> Advantages of object-oriented approach
— Uniform naming
— Services can be implemented as a set of cooperating objects
Zürich, 22.02.2013 23

24. Torsten Braun: Information-Centric Networking in Mobile Networks
SCN Object Types
function1
read
read
function2
content content
function1
data data
function3
function2
1: Content Object 2: Service Object 3: Content/Service Object
Zürich, 22.02.2013 24

25. Torsten Braun: Information-Centric Networking in Mobile Networks
Example: Real-time Audio Conferencing
Sent audio Echo Trans-
Mixing
data cancellation coding
Received audio data
Zürich, 22.02.2013 25

26. Torsten Braun: Information-Centric Networking in Mobile Networks
Real-Time Audio Conferencing Service
/echocancel
/transcode
/mix/todaysconf /transcode
/john/audiostream_original /mix/todaysconf /mix/todaysconf
/mix/todaysconf/audiostream /john/audiostream_ec /john/audiostream_trans
main main main main
/john/audiotool /echocancel /transcode /mix/todaysconf
write read write read write read write read
generated echo-cancelled transcoded
mixed audio
audio audio audio
/john/audiostream /john/ /john/audiostream /mix/todaysconf/
_original audiostream_ec _trans audiostream
Zürich, 22.02.2013 26

27. Torsten Braun: Information-Centric Networking in Mobile Networks
SCN Prototype Evaluation
publisher
4
ccndp time [s]
5 200
150
client1
1/8 3 6 100
user ccnd
1 1 2/7 CCN router 50
17/20 11/12 186 31 4
18/19 conversion 0
client2 ccndr service & 1-8 9-16 17-20
10 13/14
user 9 ccnd 15
repository
2 16 2
1-8: Client 1 retrieves bit map image (36 MB)
9-16: Client 2 retrieves JPEG image (6 MB) Torsten Braun, Andreas Mauthe, Vasilios Siris:
Service-Centric Networking Extensions,
17-20: Client 1 retrieves JPEG image 28th ACM Symposium on Applied Computing,
Coimbra, Portugal, March 18 - 22, 2013
Zürich, 22.02.2013 27

28. Torsten Braun: Information-Centric Networking in Mobile Networks
ICN and Cloud Computing
> ICN can be used to
— find/call cloud services (computation, storage)
— deploy cloud services
— support caching of data stored in the cloud
Zürich, 22.02.2013 28

29. Torsten Braun: Information-Centric Networking in Mobile Networks
EU FP7 Integrated Project:
mobile-cloud-networking.eu
> Integration of
— Radio Access Network
— Mobile Core Network
— Data Centre (computing, storage, applications)
into (decentralized) cloud computing infrastructure (management!)
> Advantages: elasticity, costs, performance, e.g., by
exploitation of user location for service provisioning → Follow Me Cloud
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30. Torsten Braun: Information-Centric Networking in Mobile Networks
Mobile Cloud Network Architecture
Zürich, 22.02.2013 30

31. Follow-Me Cloud

32. Torsten Braun: Information-Centric Networking in Mobile Networks
Benefits of ICN in Wireless Networks
> Broadcast property of wireless medium
→ single Interest to many neighbor nodes
> No beaconing required to learn about neighbor nodes
> Reduced delay and network load due to possible caching
> Request/Response based routing in mobile ad-hoc networks
(MANETs) could be replaced by Interest/Data exchange,
cf. Directed Diffusion
> Support of short mobile nodes’ encounters
> ICN architectures inherently support receiver mobility !
> Issues
— Source mobility
— Disruptions
Zürich, 22.02.2013 32

33. Torsten Braun: Information-Centric Networking in Mobile Networks
Source Mobility
> Problem
— Finding a source’s location at the beginning of and when source is moving during
communication.
> Solutions
— Routing-based approaches
– (Proactive) updating of routing tables in case of moving sources
→ issues on scalability and convergence
— Indirection
– (Home) agent forwards all Content Requests to mobile source, cf. Mobile IP.
→ location-based identifiers, cf. location/identity separation.
— Resolution
– Receiver requests location-based identifier for a content name in a Content Request.
– Approach adds resolution phase and requires resolution entities in visited networks.
> Conclusions and Suggestions
— Both content names and locators might be needed to efficiently support ICN
source mobility.
— Flexible use of content names / locators, possibly using late binding
Vasilios Siris, Torsten Braun et al.: Content-Centric Networking Architectures for Moving Objects, COST Action
IC0906, STSM Report, 2012, http://cost-winemo.org/
Zürich, 22.02.2013 33

34. Torsten Braun: Information-Centric Networking in Mobile Networks
CCN in Delay/Disruption-Tolerant (DTN)
and Opportunistic Networks
Name Origin of Data
Interest
/feeds.sf.tv/podcast/10vor10 me -
/youtube.com/movies/ mydaughter -
DesperateHousewives Encounter
… … …
/unibe.ch/braun/lecture/os/ me, +
20130219 mystudent
… … …
Possible message exchange at encounter
1. Exchange of interests, possibly with priority of own / friends’ interests
2. Exchange of relevant data
Zürich, 22.02.2013 34

35. Torsten Braun: Information-Centric Networking in Mobile Networks
Content-Centric Networks and
DTN/Opportunistic Networks
> Content-Centric Networks and Delay/Disruption-Tolerant
Networks seem to be a good match.
— No needs for beacons and neighbour lists
— Exploitation of wireless broadcast media
— Efficient exchange of Interests and Data
> Publish / Subscribe approaches might be less beneficial here.
> Issue: Possibly short encounters require
— Efficient data transfer
— Resume functionality
Zürich, 22.02.2013 35

36. Torsten Braun: Information-Centric Networking in Mobile Networks
CCN in Opportunistic Networks
> Scenario: 1 source and 1 consumer
> Evaluation of pipelining and resume functionality
— Resume: continuation of data transfer after disruption
— Transfer time of 5 MB file using PCEngines ALIX wireless mesh
nodes with different Data message sizes
Zürich, 22.02.2013 36

37. Torsten Braun: Information-Centric Networking in Mobile Networks
CCN in Opportunistic Networks: Pipelining
> Pipelining and TCP-lilke control of pipeline sizes
> Transfer time for different maximum pipeline sizes
Zürich, 22.02.2013 37

38. Torsten Braun: Information-Centric Networking in Mobile Networks
Conclusions
> Information-Centric Networking attracts huge research interest and
has potential to
— save bandwidth
— reduce delay
— save energy
— support receiver mobility
— operate efficiently in wireless networks
— support delay/disruption-tolerant and opportunistic networks
> Challenges
— storage in routers
— routing strategies
— source mobility
— more general services
— resume operations
Zürich, 22.02.2013 38

39. Torsten Braun: Information-Centric Networking in Mobile Networks
Thank You for Your Attention !
> braun@iam.unibe.ch
> http://cds.unibe.ch
> http://www.slideshare.net/torstenbraun
Zürich, 22.02.2013 39