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Network Composition between Ambient Networks

Cornelia Kappler, Siemens AG

ITG Fachgruppentreffen in Aachen, 4./5. Mai 2006

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Outline

Motivation for CompositionComposition ExamplesComposition ProcessGANS ProtocolIdentifiers in Composition Detailed Use CaseStandardizationSummary

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Motivation: Why Composition? Number and heterogeneity of networks increases Common interface for data communication (IP)

exists

But what about control signalling? Networks have different capabilities/resources

How to extend the capabilities/resources of networks?

Networks are moving

How to attach/detach moving networks? Radio resources are not the bottleneck

But how to exploit them?

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Motivation: What is Composition

A central concept of Ambient Networks is Composition

Composition is… a uniform, dynamic procedure for network interworking on the control plane

Control Plane Interworking regarding routing, addressing, mobility, QoS, security, charging,..

Uniform procedure independent of network type and technology

Dynamic procedure minimize human intervention

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Composition Examples

Creation of PAN 1BlueTooth

WLAN

WLAN Access Network in a Café

Cellular Operator Network A

Cellular Operator Network B

Automatic establishment or dynamic update of Roaming Agreements

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to th

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N 2

WLAN

UM

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Composition Examples Types of Composition

Network Integration• Involved networks merge into one common network

• E.g. creation of a PAN

Control Delegation• One AN delegates certain control functions to the other AN

• 3GPP-WLAN interworking:WLAN delegates authentication, authorization and charging to 3GPP network

• Mobility delegation a la nemo

Network Interworking• Cooperation but no control delegation

• E.g. dynamic roaming agreements

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ng c

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Network A+B

Composition Procedure

AmbientConnectivity

FE 4FE 3

CompositionFE

FE1

FE4

AmbientAmbientNetworkNetworkInterfaceInterface

AmbientAmbientNetworkNetworkInterfaceInterface

AmbientAmbientServiceServiceInterfaceInterface

AmbientAmbientResourceResourceInterfaceInterface

Ambient Control SpaceAmbient Control Space

MobilityFE

QoS-FE

FE: Functional Entity

AmbientConnectivity

FE 4FE 3

FE5

CompositionFE

FE1

FE6FE2

Ambient Control SpaceAmbient Control Space

AmbientConnectivity

FE 4FE 3

FE5

CompositionFE

FE1

FE6FE2

Ambient Control SpaceAmbient Control Space

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Security and InternetworkingEstablishment

Composition Procedure

Communication of Functional Entities (FEs) across ANI

ANI

FE A1

AN 2AN 1

GANS

Media sense

Discovery /

Composition

Media Sense

Discovery / Advertisement

Composition Agreement Negotiation

Composition Agreement Realization

FE B1

FE C1

FE A2

AN 2

FE B2

FE C2

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GANS Signaling

Protocol for communication of FEs across ANI (and intra-AN) To facilitate composition

• E.g. QoS FEs negotiate SLA Is backwards compatible with NSIS protocols

standardized by NSIS (Next Steps In Signaling) WG of IETF NSIS is a general protocol suite control signaling

• Modular and extensible• Signaling flow-related • Signaling to entities on the flow path

GANS generalization Signaling composition related rather than flow-related control signaling between FEs rather than along data path Symbolic addressing of FEs

ANI

FE yFE x

AN 2AN 1

GANS

10GANSNSIS

GANS Signaling Two layer approach:Lower layer for transporting signaling messages and common functionsUpper layer for signaling applications

• Upper layer GSLPs (Application Layer)Actual signaling application, e.g. SLA negotiation

• Lower layer GTLP (Transport Layer) provides common message transport services

– Resolves abstract name (“FEy.AN1”) into host ID/locator (e.g. IP address)

– Locates signaling peer, i.e. FE in other ANEstablishes security association between pairs of signaling FEsEstablishes signaling relation between pairs of signaling FEs

• maintained if a peer FE is relocated/reconfigured

Lower NSIS / GANS Layer

QoS NSIS Application

SLS Negotiation GANS Application

NAT/FW NSIS Application

Other GANS Applications

Abstract Addressing Resolution

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Identifiers in Composition

ProblemHow identify entities as belonging to a particular

AN• E.g. nodes, FEs,…

How dynamically change this identification upon composition?

Identification includes• Authentication• Establishing a security association• …

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Solution Each security domain (e.g. ANs α and φ) is identified by a public key

• E.g. α, φ• These identifier / public keys are exchanged in the Discovery/Advertisment phase

The associated private key is located with the security manager of the AN• E.g. Nodes B, F

Each entity owns a self-generated private/public key pair• E.g. A, A*

Each entity belonging to the same AN owns a certificate by the security manager, signed with the private key

• This way entities belonging to this AN can authenticate themselves

Identifiers in Composition

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– Rearrangement of identifiers upon composition– Example: network integration, φ absorbs α

• Security manager of AN α sends list of all entities belonging to α to security manager φ • E.g. entities A, B, C

• Security manager of AN φ issues membership certificates to A, B, C• Security manager of AN φ installs the membership certificates in each A, B, C

• with an assertion from manager of AN α• Security manager of AN α removes its own membership certificates

from A, B and C

Identifiers in Composition

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Composition Use Case: Extension of an Access Networks

Café sets up WLAN network to offer Internet Access to its customers has corresponding agreement with Operator Network

Case 1: Customer is authenticated and charged by Operator Network Case 2: Customer is authenticated and charged by Café Network

Café and Operator have SLA guaranteeing access and bandwidth

Internet

OperatorNetwork

WLAN

RADIUS

DHCP

Cafe AN

RADIUS

As 3GPP-WLAN interworkingin 23.234, but plug&play and more flexible

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Discovery WLAN Access Router has preconfigured access information

• IP address of Operator gateway ->Ambient Network ID

WLAN sends discovery message to Operator gateway

Security and Internetworking Establishment Authentication and Authorisation Establishment of IPSec tunnel for control signaling On basis of pre-established shared secret

Composition Agreement preconfigured. May detail control delegation: Who is responsible for allocating addresses? Who is responsible for authentication and authorization? Who is responsible for charging? QoS (may still adjust this via SLA negotiation)

Composition Realization

Composition Use Case: Extension of an Access Networks

Mapping onto Composition Process

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Discovery WLAN-internal logic decides to send discovery messages upon

detecting Internet connectivity Protocol for such messages Operator gateway-internal logic allows acting upon reception of

discovery messages

Dynamic automated agreement establishment between Café Network and Operator Network Preconfigured Agreements Protocol for agreement establishment

Dynamic agreement realization WLAN may have to activate DHCP Server, accounting…

Composition Use Case: Extension of an Access Networks

New Functionality needed

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Composition - Standardization

The Ambient Networks Project established aStudy Item “Network Composition” in 3GPP SA1

TR 22.980 „Network composition feasibility study; (Release 7)”

Content Purpose and benefits of composition Use cases Requirement Composition Process New functionality in 3GPP networks Relation to other functionality in evolving 3GPP architecture

• AIPN,…

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Summary Composition is a uniform, dynamic procedure for network

interworking in the control plane Feasibility study in 3GPP

Composition process Discovery/ Advertisment Security and Internetworking establishment Composition Agreement negotiation Composition Agreement realization

GANS is the protocol for negotiating and realizing Composition Agreements Based on NSIS work

ANs and their members are identified by a cryptographic key Certificates based on this key identify members Certificates are updated upon composition

Composition is a Study Item in 3GPP SA1

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Any Questions?FE5

FE4

QoS-FEAmbientConnectivity

FE 4FE 3

FE5

CompositionFE

FE1

FE6FE2

Ambient Control SpaceAmbient Control SpaceFE1

FE2Mobility

FE

AmbientConnectivity

FE 4FE 3

FE5

CompositionFE

FE1

FE6FE2

Ambient Control SpaceAmbient Control Space

Decomposing

Thank you!

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Backup

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GANS Signaling – GTLP and DEEP

DEEP (Destination Endpoint Exploring Protocol) Supporting distributed name resolution of abstract name into host ID/locator (e.g. IP

address) Flexible regarding name resolution infrastructure (DNS, more dynamic mechanisms,

…) Not tied to any particular name resolution mechanism/concept

FE x

AN 1DEEP

GANS

GSLP

GTLP

name resolution

FE y

AN 2

GANS

GSLP

GTLP

name resolution

name resolution

name resolution

GANS

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Composition Agreement - Overview

The agreement made between two ANs during the composition is called the Composition Agreement Can pre-establish and re-use Composition Agreements

• E.g. for reoccurring compositions

A Composition Agreement covers Commercial and Technical issues Details of composing AN‘s relationship

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Composition Agreement - Information Model

IdentificationIdentification

Composition Agreement

Legal IssuesLegal Issues

Service descriptionService

descriptionFinancial IssuesFinancial Issues

Monitoring &performance

reporting

Monitoring &performance

reporting

QoS related partQoS related part

Other issuesOther issues

Problem reporting&

Troubleshooting

Problem reporting&

Troubleshooting

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Different Composition Agreements

Depending on compensation involved different forms of Composition Agreements may be required medium or large amount of compensation, e.g. 3GPP networks composition

• preestablished paper Composition Agreements giving legal framework, possible range of cooperation

• During composition procedure determine specific parameters

low or no amount of compensation, e.g. small AN networks, or PANs composing• electronic Composition Agreements

Electronic Composition Agreements may revolutionize network cooperation, in a way credit cards have revolutionized the way we pay!