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Future of Networking, 20061Gregor v. Bochmann, University of Ottawa

Presentation given at the e-Science Institute, Edinburgh

September 14, 2006

Gregor v. Bochmann

School of Information Technology and Engineering (SITE)University of OttawaCanada

http://www.site.uottawa.ca/~bochmann/talks/FutureNetworking

Challenges

for the Future of Networking


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Abstract

The technical foundations for the Internet were developed more than 30years ago. Since over 10 years, it has developed into a generalcommunication infrastructure used by people and industry for a varietyof applications. While e-mail and the Web were first the most importantapplications, newer developments have introduced wirelesscommunication and new applications, including multimedia, e-commerce, etc. Certain applications, e.g. in the area of e-science, have

extreme requirements in terms of bandwidth or delay that cannot beprovided by the current Internet. - This talk will give a personal view ofthe challenges that must be faced for the future of the Internet and thedistributed applications using it, including managerial and technicalaspects. Some of these issues are (1) the integration of wireless LANsand ad-hoc networks with the wired network, (2) fast optical switching,

(3) user-empowered network management, (4) security and trustmanagement, (5) standards for distributed applications (e.g. ServiceOriented Architecture) and (6) ubiquitous computing. The talk willprovide a general discussion of these issues and present certainexamples of innovative applications.


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Overview

The current Internet and applications Research management - Grand

Challenges

Research issues in networking

Optical networks (the physical level)

Issues for distributed applications

Conclusions


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Internet: Some Characteristics

Packet switching Buffered in each router or switch (delay)

IP : connection-less Logically simple, but requiring address look-up for each packet Connection-oriented service allows for more efficient switching, e.g. new

MPLS technology

There are not enough addresses. Solutions: use of internal addresses and address translation (NAT); however, internal

addresses are not reachable or better: use IPv6

TCP : controls flow between end-systems Provides reliable information flow Many applications need a logical connection between processes running in

different hosts Not suitable for interactive voice or video traffic (retransmission introduces

delays) Not suitable for very large bandwidths (order of Gbps)

UDP : non-reliable alternative to TCP


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Some extreme applications

Large bandwidth and low delay : Videoteleconference (e.g. round-trip delay of0.1 sec at 10 000 km)

Need for multicasting: video broadcasting

(e.g. 10 Mbps to 10 000 users : 100 Gbps) Extreme large bandwidth: e.g. 10 Gbps for

e-science applications

Extremely low delays: tele-manipulation(e.g. eye surgery training); distributedmusic ensemble

Ad hoc networking (without fixed

infrastructure) people in local meeting


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7/61Future of Networking, 20067Gregor v. Bochmann, University of Ottawa

Network management and scalability

Need for interworking between differentdomains (subnetworks belonging todifferent organizations) Limited visibility

Service level agreements (static dynamic)

Large number of (scalability) Domains

Routers / switches

Host computers

Communicating devices (terminals, phones, TVs, kitchen stoves, etc.)

Security and reliability A faulty behavior of a single router should only have local impact;

idem for failures



R&D - a long path:From new idea to market place

Typical time : 20 years Example: Modeling distributed systems by state transition

diagrams 1969: Bartlett describes a communication protocol with finite state

machines (FSM) 1976: First version of SDL includes FSM notation 1977: Bochmann and Gecsei propose Extended FSMs for modeling

communication protocols 1980ies: Standardization of formal description techniques (FDTs) by

ISO and ITU, including SDL; university-based tool development 1987: Harel proposes State Charts (including certain extensions of

above notations) 1990ies: Commercial development of software tools supporting

these notations 1995 ?: Unified Modeling Language (UML) defined by OMG Around 2005: Integration between SDL and UML Version 2


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The research planning process (B)

Community-based research planning Consensus building: through mailing lists, discussions

at workshops / conferences, research collaborations

Examples:

The UK Grand Challenges: a perspective on long-term basic andapplied research

NSF (USA) Workshop on Overcoming Barriers to DisruptiveInnovation in Networks

Research program of E-NEXT (a EU - FP6 Network ofExcellence)

CoNEXT conference in Toulouse, Oct. 2005 http://dmi.ensica.fr/conext/

Canadian research network on Agile All-Photonic Networks(AAPN, funded by NSERC and 6 industrial partners)

G d Ch ll i i t
http://dmi.ensica.fr/conext/http://dmi.ensica.fr/conext/



Grand Challenges e ine in t eUK)

See http://www.ukcrc.org.uk/grand_challenges/index.cfm Definition of a Grand Challenge

A grand challenge should be defined as to have international scope, so thatcontributions by a single nation to its achievement will raise ourinternational profile.

The ambition of a grand challenge can be far greater than what can beachieved by a single research team in the span of a single research grant.

The grand challenge should be directed towards a revolutionary advance,rather than the evolutionary improvement of legacy products that isappropriate for industrial funding and support.

The topic for a grand challenge should emerge from a consensus of thegeneral scientific community, to serve as a focus for curiosity-drivenresearch or engineering ambition, and to support activities in which they

personally wish to engage, independent of funding policy or politicalconsiderations. (Note: the quotes, here and in subsequent slides, indicatethat the text is copied from the source documentation)

The following two slides are from Robin Milners talkA scientifichorizon for computingat the World Congres 2004 of the InternationalFederation for Information Processing (IFIP), held in Toulouse.
http://www.ukcrc.org.uk/grand_challenges/index.cfmhttp://www.ukcrc.org.uk/grand_challenges/index.cfm



Grand Challenge Exercise



UK Grand Challenge Proposals

Note: No GC is dedicated to networking issues



Ubiquitous ComputingGrand Challenge

Combination of GC 2 and GC 4 See http://www-dse.doc.ic.ac.uk/Projects/UbiNet/GC/index.html

Objective:We propose to develop scientific theory and the designprinciples ofGlobal Ubiquitous Computingtogether, in a tight

experimental loop.

Engineering challenges: design devices to work from solar power, are aware of their

location and what other devices are nearby, and form cheap,efficient, secure, complex, changing groupings and interconnectionswith other devices;

engineer systems that are self-configuring and manage their own

exceptions; devise methods to filter and aggregate information so as to cope

with large volumes of data, and to certify its provenience.

business model for ubiquitous computing, and other human-levelinteractions.

b
http://www-dse.doc.ic.ac.uk/Projects/UbiNet/GC/index.htmlhttp://www-dse.doc.ic.ac.uk/Projects/UbiNet/GC/index.htmlhttp://www-dse.doc.ic.ac.uk/Projects/UbiNet/GC/index.htmlhttp://www-dse.doc.ic.ac.uk/Projects/UbiNet/GC/index.html



Ubiquitous ComputingGrand Challenge (ii)

Scientific challenges: discover mathematical models for space and mobility, and develop their

theories; devise mathematical tools for the analysis of dynamic networks; develop model checking, as well as techniques to analyse stochastic

aspects of systems, as these are pervasive in ubiquitous computing; devise models of trust and its dynamics;

design programming languages for ubiquitous computing. A comment: It is not clear where in the context of

ubiquitous computingNetworkingstops and Computingstarts. In fact, networking involves much distributedsystems management (including databases); and for theInternet applications, the application layer protocols arejust as important as (if not more than) the underlyingnetworking protocols.

Note:Milner has developed a new description formalism Bigraphs forMobile Processes

( see http://www.cl.cam.ac.uk/users/rm135/ )
http://www.cl.cam.ac.uk/users/rm135/http://www.cl.cam.ac.uk/users/rm135/



Research topics in Networking

Issues Network layer:

new wireless technologies: cellular, LAN, PAN, ad-hoc, sensor, etc. Integration with wire-line Internet Higher bandwidth

Inter-layer control and management according to application needs

Physical layer: technology push Faster electronic components, e.g. 10 Gbps Ethernet Fast optical switching Trend: IP over Dense Wavelength Division Multiplexing (DWDM); elimination of

intermediate layers of ATM, SONET; however, it may be IP over MPLS over DWDM.

Application layer many new applications: importance of multimedia application will increase New protocols for organizing applications: Web Services, Grid, peer-to-peer New ways for identifying and searching services, including concern for security and

trust

Networkservice

Architectural levels of Networking Technologya narrow-waisted hourglass model:

O i B i



Overcoming Barriers toDisruptive Innovation in Networks

Workshop organized by NSF (USA) Overcoming Barriers to Disruptive Innovation in

Networking(Jan. 2005) see http://www.arl.wustl.edu/netv/noBarriers_final_report.pdf

Starting point: The Internet is ossified: Adopting a new

architecture not only requires modifications to routers andhost software, but given the multi-provider nature of theInternet, also requires that ISPs jointly agree on thatarchitecture. The need for consensus is doubly damning;not only is agreement among the many providers hard to

reach, it also removes any competitive advantage fromarchitectural innovation. This discouraging combination ofdifficulty reaching consensus, lack of incentives fordeployment, and substantial costs of upgrading theinfrastructure leaves little hope for fundamentalarchitectural change.
http://www.arl.wustl.edu/netv/noBarriers_final_report.pdfhttp://www.arl.wustl.edu/netv/noBarriers_final_report.pdf


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NSF workshop (ii)

Requirements for the new Internet: Minimize trust assumptions: the Internet originally viewed network

traffic as fundamentally friendly, but should view it as adversarial; Enable user choice: the Internet was originally developed independent of

any commercial considerations, but today the network architecture musttake competition and economic incentives into account;

Allow for edge diversity: the Internet originally assumed host computerswere connected to the edges of the network, but host-centric assumptionsare not appropriate in a world with an increasing number of sensors andmobile devices;

Design for network transparency: the Internet originally did notexpose information about its internal configuration, but there is value toboth users and network administrators in making the network more

transparent; and Meet application requirements: the Internet originally provided only a

best-effort packet delivery service, but there is value in enhancing (addingfunctionality to) the network to meet application requirements.

Identified 7 areas of research (see next slides)


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7 research areas:

Security Economic incentives

Address binding

End-host assumptions

User-level route choice

Control and management

Meeting application requirements

(see next slides)


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Security

Problem indications traffic must be viewed as adversarial rather than cooperative To take one example, a single mistyped command at a router at one ISP

recently caused widespread, cascading disruption of Internet connectivityacross many of its neighbors.

Benefits of better security1. improve network robustness through protocols that work despite

misbehaving participants,2. enable security problems to be addressed quickly once identified,3. isolate ISPs, organizations, and users from inadvertent errors or attacks;4. prevent epidemic-style attacks such as worms, viruses, and distributed

denial of service;5. enable or simplify deployment of new high-value applications and critical

services that rely on Internet communication such as power grid control,on-line trading networks, or an Internet emergency communicationchannel; and

6. reduce lost productivity currently aimed at coping with security problemsvia patching holes, recovering from attacks, or identifying attackers.


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Security (ii)

Interesting architectural approaches: prevent denial of service by allowing a receiver to

control who can send packets to it making firewalls a fully recognized component of the

architecture instead of an add-on that is either turned

off or gets in the way of deploying new applications. Aclean specification for security that makes clear thebalance of responsibility for routers, for operatingsystems and for applications can move us from thehodge-podge of security building blocks we have today

to a real security architecture A careful design of mechanisms for identity can

balance, in an intentional way rather than by accident,the goals of privacy and accountability. Ideally, thedesign will permit us to apply real world consequences(e.g. legal or financial) for misbehavior.


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Economic incentives

Proposition:A future design for an Internet should take into

account that a network architecture induces anindustry structure, and the economic structure

of that industry. The architecture can use userchoice (to impose the discipline of competitionon the players), indications of value flow (tomake explicit the right direction of payment

flow), and careful attention to what informationis revealed and what is kept hidden (to shapethe nature of transactions across a competitiveboundary).


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Address binding

Problem with IP addresses There are not enough solution: IPv6 They serve as machine identity (instead of only identifying the

network attachment point, the location) this leads to difficulties for mobile devices (e.g. Mobile IP routing is not

straightforward IP address changing dynamically)

IP address (as machine identifier) also used for security Proposed solution approaches

Host Identity Protocol It provides secure host identification Routing is based on IP addresses that are treated only as ephemeral

locators

end-points (as equated with physical machines or operatingsystems) need not have any globally known identity at all. Instead,application level entities have shared identities , and higher levelname spaces such as a redesigned DNS are used to give globalnames to services, so that they can be found.


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End host assumptions

Issues with sensor networks sensors may be intermittently connected

routing may be based on data values

Solution approaches: Overlay networks Overlay for realizing special routing functions,

e.g. diffusion routing

Overlay for delay-tolerant routing (e.g. for e-mail; also allowing access in a variety ofimpoverished and poorly connected regions )


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User-level route choice

Objectives:increase the users choice andintroduce more competition Instead of applying a "one-size-fits-all" policy to their

traffic, ISPs could perform routing and trafficengineering based upon the user traffic preferences offer unique policies such as keeping all traffic withinthe continental United States for security reasons.

This selection creates a more complex economic

environment; it offers potential rewards in user choiceand competition, but requires solutions to issues ofaccounting, pricing, billing, and inter-ISP contracts.


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Control and management

Statement: Management of the Internet is very complex(for all parties involved)

Solutions: not clear (there are references to ongoingwork)

One problem: limited visibility of internal parameters fromoutside the network (opaqueness) A network should support communication of operationally relevant

information to each other. Such information could be aggregatedand analyzed, thereby facilitating load balancing, fault diagnosis,anomaly detection, application optimization, and other traffic

engineering and network management functions. One needs a compromise between information hiding and visibility

for management.


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Meeting application requirements

Protocol layer architecture is a narrow-waisted hourglass model

Additional requirements: QoS control, multicast, anycast,

policy-based routing, data caching

Possible solutions: Add more functions to IP layer

Use overlay networks to provide additional functions

IP Networkservice


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Some personal comments

Overlay networks Principle: A certain number of servers connected to the Internet

play the role of virtual routers in the overlay network. Note: Thisis the way MBone implements multicasting over the current IP Internetservice.

The NSF workshop stresses the use of overlay networks for

experimentation with new approaches Could such architectures present the final solution ?

NO, overlay technology, such as peer-to-peer computing, may be useful forcertain applications, but cannot be a solution for building a network

Existing well-known applications

Napster and BitTorrent media distribution, and other peer-to-peerapplications

Multicasting of multimedia presentations, possibly including differentquality variants

A Testbed: US-based Planetlab http://planet-lab.org/; see alsohttp://www.arl.wustl.edu/netv/main.html
http://planet-lab.org/http://www.arl.wustl.edu/netv/main.htmlhttp://www.arl.wustl.edu/netv/main.htmlhttp://planet-lab.org/http://planet-lab.org/http://planet-lab.org/


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Some personal comments (2)

Lightpaths -Underlay Networks ? Experimental research networks provide high-bandwidth

lightpaths between different sites for e-science and otherapplications that require guaranteed high-bandwidth connections. For an overview of current applications, see

http://www.internet2.edu/presentations/fall05/20050920-lambdas-sauver.htm

User-Controlled Lightpath Provisioning (UCLP) allows the e-scienceusers to establish lightpaths dynamically through a graphic userinterface. Note: UCLP has been initiated in Canada with partial funding from

Canarie (the Canadian research network), see for instancehttp://www.uclp.ca

These networks make use of user-owned fibers and condominiumfacilities for long-haul transmission and switching

This is not an overlay, but also provides a new networkingservice, independently from the existing Internet. TheInternet can be built on top of it.
http://www.internet2.edu/presentations/fall05/20050920-lambdas-sauver.htmhttp://www.internet2.edu/presentations/fall05/20050920-lambdas-sauver.htmhttp://www.uclp.ca/http://www.uclp.ca/http://www.uclp.ca/http://www.internet2.edu/presentations/fall05/20050920-lambdas-sauver.htmhttp://www.internet2.edu/presentations/fall05/20050920-lambdas-sauver.htmhttp://www.internet2.edu/presentations/fall05/20050920-lambdas-sauver.htmhttp://www.internet2.edu/presentations/fall05/20050920-lambdas-sauver.htmhttp://www.internet2.edu/presentations/fall05/20050920-lambdas-sauver.htm


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Packets vs. (virtual) connections The old debate between packet switching and circuit switching

(from the 1970ies) is not dead !! Distinction: In packet switching, the header of the

packet/frame/cell/burst contains the destination address; in circuitswitching, it contains a number (label) identifying the circuit (in TDM,this number is the timing position).

MPLS (label switching) provides packet switching over dynamicallyestablished paths (virtual connections)

Optical lightpaths are connection-oriented. It is expected thatexisting ROADM (Reconfigurable optical add/drop multiplexers)technology will be widely deployed within a few years; see for instancehttp://lw.pennnet.com/Articles/Article_Display.cfm?Section=ARTCL&ARTICLE_ID=203231&VERSION_NUM=1

An optical lightpath at a given wavelength is very large, typically 10Gbps. Sub-multiplexing of a lightpath in the time domain isproposed by many research projects; Sharing between packets or virtual connections ??
http://lw.pennnet.com/Articles/Article_Display.cfm?Section=ARTCL&ARTICLE_ID=203231&VERSION_NUM=1http://lw.pennnet.com/Articles/Article_Display.cfm?Section=ARTCL&ARTICLE_ID=203231&VERSION_NUM=1


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Appearently contradictory approaches IP : packet-oriented switching The concept of virtual connections are natural for

providing QoS guarantees. The lower layers of broadband wireline networks appear

to use connection-oriented technologies. The overlay networks would like to obtain more visibility

about the performance aspects of the underlying IPservice.

Suggestion: Maybe there should be more visibility atthe IP service level about the underlying virtual andphysical circuits that exist within the network and theirperformance parameters; and the application shouldhave some choice about the routing of its data.


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Optical networks

Currently deployed: optical transmission with DWDM

Some optical switching

Note: most optical switches convert the opticalsignal into the electrical domain and perform theswitching in the electrical domain.

Expected to be deployed:

ROADM used for transparent optical switching inthe millisecond speed range; good for protectionswitching and bandwidth on demand.


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Burst switching

Question:Can one do packet switching in the opticaldomain (without oeo conversion)?

At a switching speed of 1 s, one could switch bursts of10 s length (typically containing many packets)

Traditional packet switching involves packet buffering inthe switching nodes. Should one introduce optical buffersin the form of delay lines?

The term burst switching originally meant nobuffering: in case of conflict for an output port, one of

the incoming bursts would be dropped.

Note:Burst switching allows to share the large opticalbandwidth among several virtual connections.


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AAPN

An NSERCResearch Network

The Agile

All-Photonic Network

Project leader: David Plant, McGill University

Theme 1: Network architecturesGregor v. Bochmann, University of Ottawa

Theme 2: Device technologies for transmission and

switching


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AAPN Professors (Theme 1 in red)

McGill: Lawrence Chen, Mark Coats,Andrew Kirk, LorneMason, David Plant (Theme #2 Lead), and Richard Vickers

U. of Ottawa: Xiaoyi Bao, Gregor Bochmann (Theme #1Lead), Trevor Hall, and Oliver Yang

U. of Toronto: Stewart AitchisonandTed Sargent McMaster: Wei-Ping Huang

Queens: John Cartledge (Theme #3 Lead)

Note: Theme 2 deals with device technologies fortransmission and switchingFor further information see: http://www.aapn.mcgill.ca/


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The AAPN research network

Our vision: Connectivity at the end of thestreet to a dynamically reconfigurablephotonic network that supports highbandwidth telecommunication services.

Technical approach: Simplified network architecture (overlaid stars) Specific version of burst switching

Fixed burst size, coordinated switching at core node for all inputports (this requires precise synchronization between edge nodes

and the core) See for instance

http://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Hall05a.pdf

Burst switching with reservation per flow (virtual connection),either fixed or dynamically varying

See for instancehttp://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Agus05a.pdf
http://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Hall05a.pdfhttp://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Hall05a.pdfhttp://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Agus05a.pdfhttp://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Agus05a.pdfhttp://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Hall05a.pdf


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Future of Networking, Lausanne, 200537

Edge node with slotted transmission(e.g. 10 Gb/s capacity per wavelength)

Opto-electronic interface

Fast photonic core switch

(one space switch per wavelength)

-Provisions sub-multiples of a

wavelength

- Large number of

edge nodes

Agile All-Photonic Network

Overlaid stars architecture


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Starting Assumptions

Avoid difficult technologies such as Wavelength conversion

Optical memory

Optical packet header recognition and replacement

Current state of the art for data rates,channel spacing, and optical bandwidth

Simplified topology based on overlaid stars

Edge based control in small/medium sizeedge nodes


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Starting Assumptions (ii)

No distinction between long-haul and metronetworks

Fast optical space switching (


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Bandwidth allocation schemes

For flows between edge nodes Optical wavelength: Whole wavelength (for

large bandwidth flows) like the PetaWeb explored byNortel Networks

Optical circuit: One or several time slots withineach TDM frame

Burst switching: individual bursts (with orwithout reservation)

Coordination by controller at core node Signaling protocol between edge and core node

(suitable for metro and long-haul networks)


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Integration higher layer (MPLS and IP)

MPLS flows passing through the AAPN With N edge nodes, there are N x N links

in the AAPN (scalability problem for IProuting protocol)

Virtual router star architecture

OSPF sub-areas How to find optimal inter-area route

(work sponsored

by Telus)


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Deployment aspects - Questions

Long-haul or Metro ? connectivity at the end of the street; to a server farm

AANP as a backbone network ?

High capacity (many wavelengths) or low capacity(single or few wavelengths) ?

Multiple core nodes ? For reliability

For load sharing Transmission infrastructure ?

Using dedicated fibers

Using wavelength channels provided by ROADM network

Issues for


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Issues for

Distributed applications Multimedia Ubiquitous computing and location-awareness

Service-oriented architecture and Grid

computing Making it easy for the end-user

Scalability peer-to-peer computing

Related technologies Security

Trust management

Software development technology


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Distributed multimedia applications

The basics are relatively well understood Video requires high bandwidth

Conversational applications require short transmissiondelays

In many cases, multicasting is required (possiblyprovided through the overlay approach)

Aspects to be further explored Shared virtual environments, e.g. for collaborative work

or games Tactile applications; tele-haptics require very short

delays

Quality of service management for multiple receivers;media transcoding

Example: Locating suitable


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Example: Locating suitabletranscoding servers (El-Khatib)

See http://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/ElKh04c.pdf

Ubiquitous computing and


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Ubiquitous computing andlocation-awareness

See Grand Challenge Example: Some issues encountered in our

project on teleconferencing for mobile users Problem: In ad-hoc environment (e.g. on a trip) find out what

devices may be useful to the user to establish a video-conference

with a friend in another country. Consider quality of service (QoS) negotiation to find most suitable

devices according to the users preferences and the remote site. Assumption: User has a PDA that can detect through short-range

wireless communication (e.g. Bluetooth) which devices areavailable in the environment.

Approach: We use a Home Directory to store the preferences ofthe user; it must be down-loaded into the PDA for processing (itmay be a rented PDA). Seehttp://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/ElKh04a.pdf

Example: Device selection in an
http://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/ElKh04a.pdfhttp://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/ElKh04a.pdf


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Example: Device selection in anad-hoc environment

Internet

Bobs HDA

Alices HDA

Alice

PA

(PDA)

1

2 3

4

44

75

56

5

4

4

4

555

7

Example: Session mobility


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Example: Session mobilityand QoS adaptation

QoSNegotiation

and Selection

Agent User

Context

Agent

Personal Agent

User Profile

Service

Registry

Communic-

ation Agent

Service

Discovery

Agent

Service-oriented architecture


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Service oriented architectureand Grid applications

Concepts RPC for accessing services

Directory service

Realizations: CORBA, Jini(Java environment)

WS and SOA:use similar concepts Use HTTP and SOAP (based on XML)

Workflow specifications (BPEL, etc.)

Advantages: use of HTTP (firewalls)

programming language independent (like CORBA)


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Notes on XML

text-oriented encoding of data structures (basedon SGML, like HTML)

used for storage and/or transmission

Data structure (type) definition in the form ofDTD or XML Schema

Developed by WWW Consortiumhttp://www.w3.org/

Used for a multitude of applications, see forinstance list of resources athttp://www.extensinet.com/
http://www.w3.org/http://www.extensinet.com/http://www.extensinet.com/http://www.w3.org/


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WS: Example applications

E-commerce: Historical: First e-commerce: Electronic Data Interchange (EDI)

Standards about data elements required in purchase order, invoice, shippingdocuments, etc.

Standard coding format Message transmission over telephone or leased lines

Transition to the use of the Internet: Development of SOAP (new codingstandard based on XML)

Nowadays: many new applications and developments See Electronic Business using XMLhttp://www.ebxml.org/ OASIS http://www.oasis-open.org/

Resource sharing E-science projects - Grid computing Network management, e.g. UCLP (see above)

Need for common understanding ofinformation (semantics) Work by the W3C on the Semantic Webhttp://www.w3.org/2001/sw/
http://www.ebxml.org/http://www.oasis-open.org/http://www.w3.org/2001/sw/http://www.w3.org/2001/sw/http://www.oasis-open.org/http://www.oasis-open.org/http://www.oasis-open.org/http://www.ebxml.org/


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Making it easy for the end-user

Everyday use(for our normal day activities) Content creation by the end-user

See It's A Whole New Web (Businessweek)http://www.businessweek.com/magazine/content/05_39/b3952401.htm
http://www.businessweek.com/magazine/content/05_39/b3952401.htmhttp://www.businessweek.com/magazine/content/05_39/b3952401.htm


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Peer-to-peer computing

Scalability to the millions and more Load is shared on a peer-to-peer basis

Individual servers may come and go

Robustness of the overall system Example of service:

distributed storage and search facility

Not only applicable to file sharing Note: this is an overlay system


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Related technologies Security Trust management

Software development technology


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Security

Services Privacy of message exchanges

Integrity of messages

Authentication of users and devices

Signature with non-repudiation

Cryptographic technologies Secret key encryption

Public key encryption (RCA, elliptic, etc.)

Hash functions, etc.

Secure private and public networks

Integration of security into application layer protocols

New types of applications Electronic cash


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Trust management

trust is the outcome ofobservationsleadingto thebeliefthat the actions of another maybe relied upon, withoutexplicitguarantee,to achieve agoalin a risky situation

-- Greg ElofsonKey elements

Observations (experience, interaction)

Belief (assumption)

Goal (expectation)

Without guarantee (risk)

Subjective


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Trust: An example scenario

Alice visits her friend Bob who lives since a year in a foreigncountry. She wants to invite Bob and some of his friends forsupper. She does not know which restaurant to choose,since she wants tasty food, a nice atmosphere and goodservice.

In her own city, she has experienced many restaurants and

she knows the restaurants she would choose depending onhow important food, atmosphere and service is for theoccasion. She trusts these restaurants, based on her pastexperience.

Now she asks Bob for his experience in order to select anappropriate restaurant. She trusts Bob for telling her the

truth and for evaluating restaurants based on similarcriteria as herself. Then she selects a restaurant with good food, because the

friends find food more important than service. (Note: food isthe utility to be optimized)


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Some observations Trust is used for decision making Trust means a prediction of the outcome of a service invocation

E.g. based on the experience, we predict that the chosen restaurant will provide tastyfood.

Our trust model based on statistics and Bayesian estimationhttp://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Shi04a.pdf

The space of possible outcomes usually depends on the context in which the trust model isused

Trust is the estimation of a probability distribution over the possible outcomes of experiences

Our own experience is more reliable than the experience of peers, however,peers may have more experiences than we. Question: can we trust the recommendations of others ? Our recommendation evaluation algorithm

http://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Shi05a.pdf

Weight each recommendation according to the trust in the recommender The trust in the recommender will decrease if a given recommendation is unfair How can one determine the fairness of a recommendation ??

How detailed should the trust model be ? Should one distinguish different dimensions, e.g. food, atmosphere and service, or

simply have one evaluation category, e.g. the restaurant being either excellent, good,bad or very bad ?

Is it possible to determine the expected error of predictions?
http://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Shi04a.pdfhttp://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Shi05a.pdfhttp://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Shi05a.pdfhttp://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Shi05a.pdfhttp://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Shi04a.pdf


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Transactions based on trustExisting access control model for mobile users: Autonomic

Distributed Authorization Middleware

Systematic development of


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Systematic development ofdistributed applications

UK Grand Challenge Dependable SystemsEvolution use of assertions for defining component requirements

verifying compiler as a goal Personal comment: Is this the right approach ??

UML - formalizing its semantics Work in Ottawa:

Defining requirements by scenarios (seehttp://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Sand05a.pdf)

Using notations of Activity Diagrams or Use Case Maps (UCMs) (see

http://www.site.uottawa.ca/~damyot/pub/index.shtml ) Define semantics of these languages based on Coloured Petri nets

Consideration of performance parameters (seehttp://www.sce.carleton.ca/rads/puma/ )

Relationship to workflow modeling, transaction processing, BPEL
http://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Sand05a.pdfhttp://www.site.uottawa.ca/~damyot/pub/index.shtmlhttp://www.sce.carleton.ca/rads/puma/http://www.sce.carleton.ca/rads/puma/http://www.site.uottawa.ca/~damyot/pub/index.shtmlhttp://beethoven.site.uottawa.ca/dsrg/PublicDocuments/Publications/Sand05a.pdf


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Conclusions

Networking implies different system layers physical transmission

network services and their management

distributed applications

There is technology push (higherbandwidth, wireless transmission,computing power) and application pull(after e-mail and WWW:IP telephony and

conferencing, VOD, e-commerce, e-society) There are many interesting topics of

research relevant to the future of