Authorization of a QoS pathbased on Generic AAA

SC2002 Baltimore NOV 16-22

Bas van OudenaardeAdvanced Internet Research Group

University of Amsterdamoudenaar@science.uva.nl

EU IST-2001-32459

Content

● Introduction

● Concepts of Generic Authorization, Authentication & Accounting (AAA)

● Authorization / Control models

● Authorized path discovery

● AAA server authorization interaction

● Test bed / Bandwidth on Demand Server

● Conclusions

Introduction:● Users require guaranteed high bandwidth connections ● Project: middleware solution for authorization of Quality of Service (QoS) path● As network resources need to be managed with different security systems and policies, this project identifies the major problems and tries to find inter-Grid level mechanisms capable to interoperate with the administrative domain specific authentication, authorization and management rules and procedures ● Protoytpe:Bandwidth on Demand server based on Generic AAA

Generic AAA:● AAA Server: may be involved in: Authorization, Authentication, Accounting

● AAA request < > Driving Policy

● Behavior of the generic part is determined by the combination of Driving policies, ASM's and AAA requests

...Continue, Generic AAA

● Group has been participating on defining concepts for Generic AAA since march 1999 when AAA WG was formed at IETF-44.● Work became IRTF subject later on (AAAARCH RG).● RFC’s 2903 – 2906 describes framework, architecture, example applications and requirements.● Optical Networking within grid environment is a research application for Generic AAA.

Generic AAA Architecture – RFC2903

PolicyDecision

Point

PolicyEnforcement

Point

Fundamental idea’sinspired by work of the IETF RAP WGthat in RFC 2753 describes a frameworkfor Policy-basedAdmission Control.

Foundation for COPS

The point where policy

decisions are made.

The point where the policydecisions are actually enforced.

RequestDecision

PolicyRepository

Basic Goal Generic AAA: Allow policy decisions to be made by multiple PDP’s belonging to different administrative domains.

Generic AAA Architecture – RFC2903

ApplicationSpecificModule

PolicyEnforcement

Point

Achieve goal by separating the logical decision process fromthe application specificparts within the PDP.

RequestDecision

RuleBasedEngine

PolicyRepository

PDP

Generic AAA Architecture – RFC2903

ApplicationSpecificModule

PolicyEnforcement

Point- allow RBE’s to talk to each other andexchange messages that can only have"boolean answers".- Policies are hidden from original requestor.

RequestDecision

RuleBasedEngine Policy

RepositoryApplicationSpecificModule

RuleBasedEngine

PolicyRepository

Users

ApplicationSpecificModule

RuleBasedEngine

PolicyRepository

Budgets

HR Dept.Finance Dept.

Service Provider

User A

AAAServer

AAAServer

AAAServer

Institute / Enterprise

Generic AAA Framework – RFC2904

3 fundamentally different user initiated authorization sequences.

Service

AAA

User

Service

AAA

User

Service

AAA

User

Pull sequence

NAS, RSVP

Agent sequence

Brokers, agents.

Push sequence.

Token Based AccessKerberos Tickets

1

11

22

2

3 3 3

4

4

4

Generic AAA Framework – RFC2904

Separating the User Awareness from the Serviceyield Roaming Models: Example roaming pull model.

Service

AAA

User1 2 5

6

AAA

3 4

User HomeOrganization

ServiceProvider

Authorization / Control models

● Network nodes & network links; where the relevant parameters are under the control of an AAA Server

● Parameters are governed by a set of policies

● Consider; Simple unidirectional QoS path between two nodes:

Individual Control modelPartial Control modelFull Control model

Individual Control model

N0

AAA

AAA

N1

AAA

Partial Control model

N0

AAA

N1

AAA

Full Control model

N0

AAA

N1

Authorized path discovery

N0

AAA0

Nn

ĩ

• QoS path through multiple administrative domains

• AAA servers > Mechanism for advertising the connections they can establish

• Start with simplest QoS path > Full Control model

• Logical network link ĩ iso physical network link

•Decision tree for authorization of QoS elements

Example of AAA server authorization interactions

AAA1,2

AAA1

AAA2

N1

N2ĩ

D0

AAA0

N0

Nnl

2,nl0,1

D1 D

0

Test bed / Bandwidth on Demand

• Focus on optical networks; layer 1, 2 technologies

• 802.1Q VLAN switches

• Construct a private network

Cabletron SS 6000

802.1Q VLANSwitch

AAA client

ControlPort

Grid Domain A

Optical N/WProvider

FE NetworkPorts

FE NetworkPorts

Cabletron SS 6000

802.1Q VLANSwitch

SNMP ControlPort

Lightpath

1GB

Grid Domain B

Generic AAA BoD: Agent sequence; Full Control modelauthorizing QoS path access via VLAN’s

“Internet”

Globus

AAA clientGlob

us

AAA clientAAA ServerAAA clientGlob

usGlob

usGlob

usXML/SOAP

XML/SOAP

Grid Domain A

Optical N/WProviderProxy

GB NetworkPorts

GB NetworkPorts

CLI or XML

Grid Domain B

Replace fiber for GMPLS / or DWDM technology

“Internet”

GMPLS

AAA clientGlob

us

AAA clientGlob

us

AAA clientAAA ServerAAA clientGlob

usGlob

usGlob

us

Optimized TCP/IPOptimized TCP/IP

Example BoD request

-<AAARequest version="0.1" type="BoD">- <AuthorizationData>   <Credential type=”simple”> <ID>person1</ID> <Key>1#fdjkj9#esn34k</Key> </Credential> </AuthorizationData> <BodData> <Source>100.10.20.30</Source>   <Destination>110.1.2.3</Destination>   <Bandwidth>2500</Bandwidth>   <StartTime>now</StartTime>   <Duration>3600</Duration>  </BodData></AAARequest>

Example of BoD driving Policy

if( ( ASM::Authorizer.authorize( Request::AuthorizationData.Credential.ID, Request::AuthorizationData.Credential.Key ))then( ASM::RM.BoD( Request::ServiceData.SwitchData.Source, Request::ServiceData.SwitchData.Destination, Request::ServiceData.SwitchData.Bandwidth, Request::ServiceData.SwitchData.StartTime, Request::ServiceData.SwitchData.Duration ) ; Reply::Answer.Message = "Request successful")else( Reply::Error.Message = "Request failed")

Summary / Conclusions

● AAA server behavior > ASMs, policies, AAA msg● RBE only takes logical decisions ( multi domain )● Implement ASMs for difficult tasks to support RBE

● Multi domain challenge > policies, AAA msg● ASM template supporting services, switching technologies● Building complex decision network <> scalability, stability and performance

Thank you !