Connect. Communicate. Collaborate Federated peering the NREN way: eduGAIN and eduroam Diego R. Lopez (RedIRIS) Klaas Wierenga (SURFnet)

Connect. Communicate. Collaborate

Federated peering the NREN way:eduGAIN and eduroam

Diego R. Lopez (RedIRIS)

Klaas Wierenga (SURFnet)

Connect. Communicate. CollaborateContents

• The drivers for

(con-)federations (Diego)• The eduroam case (Klaas)• The eduGAIN case (Diego)• Universal single signon aka

DAMe (Klaas)


The drivers for con-federations

Giving federations a taste of their own medicine

Connect. Communicate. CollaborateAs Federations Grow

• The risk of dying of success– Do we really need to go on selling the federated idea?

• Different communities, different needs– Not even talking about international collaboration– Different (but mostly alike) solutions– Grids and libraries as current examples– And many to come: Governments, professional

associations, commercial operators,…• Don’t hold your breath waiting for the Real And Only Global

Federation


ConfederationsFederate Federations

• Same federating principles applied to federations themselves– Own policies and technologies are locally applied

• Independent management– Identity and authentication-authorization must be properly

handled by the participating federations• Commonly agreed policy

– Linking individual federation policies– Coarser than them

• Trust fabric entangling participants– Through each federation’s fabric– P2P trust must be dynamically built

Connect. Communicate. CollaborateFirst Steps

• Simplifying user collaboration across whatever border is an

excellent selling argument

– Making the whole promise of the VO idea

– eduroam fast worldwide success is a clear example

• Following a middle-both-ways approach

– Top-down: projects like GEANT2

– Bottom-up: initiatives like ShibEnableºº

Connect. Communicate. CollaborateTechnologies

• Lingua franca– Syntax: SAML (converging to 2.0) Shibboleth and

eduGAIN profiles– Semantics: eduPerson, SCHAC

• Trust fabric– Public key technologies (if not infrastructures)– Component identifiers and registries– Metadata repositories

Connect. Communicate. CollaboratePolicy and Legal Matters

• The PMA model has proven extremely useful– Consensual set of guidelines– Peer-reviewed accreditation

• Legal matters: Hic sunt leones– For techies like us– Privacy– Liability– More or less manageable in the case of (national)

federations


The eduroam case

Confederation avant-la-lettre

Connect. Communicate. CollaborateThe goal of eduroam

• “open your laptop and be online”

• To build an interoperable, scalable and secure authentication infrastructure that will be used all over the world enabling seamless sharing of network resources

Connect. Communicate. Collaborateeduroam concepts

• Based on reciprocal (free) access• NREN community• Authentication at home• Authorisation at visited institution


eduroam: Ubiquitous Network Access Connect. Communicate. Collaborate

RADIUS server

University B

RADIUS server

University A

SURFnet

Central RADIUS

Proxy server

Authenticator

(AP or switch) User DB

User DB

Supplicant

Gast

piet@university_b.nl

StudentVLAN

CommercialVLAN

EmployeeVLAN

data

signalling

• Trust based on RADIUS plus policy documents

• 802.1X

• (VLAN assignment)


A General model for eduroam interactions Connect. Communicate. Collaborate

RADIUS@visited RADIUS@home

Id RepositoryResource (AP)

RADIUS + TLS Channel(s)

Tue Oct 10 00:05:15 2006: DEBUG: Packet dump:*** Received from 145.99.133.194 port 1025 ....Code: Access-RequestIdentifier: 1Authentic: k<145><206><152><185><0><0><0><249><26><0><0><208>D<1><16>Attributes: User-Name = "[email protected]" NAS-IP-Address = 145.99.133.194 Called-Station-Id = "001217d45bc7" Calling-Station-Id = "0012f0906ccb" NAS-Identifier = "001217d45bc7" NAS-Port = 55 Framed-MTU = 1400 NAS-Port-Type = Wireless-IEEE-802-11 EAP-Message = <2><0><0>-<1>[email protected] Message-Authenticator = <27>`-y<208><232><252><177>.<160><230><177>I<218><243>\

Tue Oct 10 00:17:32 2006: DEBUG: Handling request with Handler 'TunnelledByTTLS=1, Realm=/guest.showcase.surfnet.nl/i'Tue Oct 10 00:17:32 2006: DEBUG: Deleting session for [email protected], 145.99.133.194,Tue Oct 10 00:17:32 2006: DEBUG: Handling with Radius::AuthFILE: SC-GUEST-IDTue Oct 10 00:17:32 2006: DEBUG: Reading users file /etc/radiator/db/showcase-guest-usersTue Oct 10 00:17:32 2006: DEBUG: Radius::AuthFILE looks for match with [email protected] [[email protected]]Tue Oct 10 00:17:32 2006: DEBUG: Radius::AuthFILE ACCEPT: : [email protected] [[email protected]]Tue Oct 10 00:17:32 2006: DEBUG: AuthBy FILE result: ACCEPT,Tue Oct 10 00:17:32 2006: DEBUG: Access accepted for [email protected] Oct 10 00:17:32 2006: DEBUG: Returned TTLS tunnelled Diameter Packet dump:Code: Access-Accept

Connect. Communicate. Collaborateeduroam Hierarchy Connect. Communicate. Collaborate

(virtual) eduroam root

APAN rootEuropean root (America’s root). . . .

.nl

.ac.uk

.dk

. . .

.au

.cn

. . .

.edu

.us

. . .

.hr

.es

. . .

Connect. Communicate. Collaborateeduroam Confederations

• Regions have their own stage of development and pace• Regions have their own regional policies (with delegation to national federations)• Policies will be aligned as much as possible


The European eduroam Policy

• Mutual access• Home institutions are/remain responsible for their users

abroad • Members are European NRENs• Members guarantee required security levels by their

participants• Members promote eduroam in their countries• European eduroam may peer with other regions

Connect. Communicate. CollaborateNational Policies

• Mutual access• Members are connected institutions• Home institution is/remains responsible for its users

behaviour.• Home institution is responsible for proper user

management• Home and visited institution must keep sufficient logdata• Appropriate security levels

Connect. Communicate. CollaborateLimitations

• Authentication = authorisation• Hierarchical trust establishment AND hierarchical routing of

access requests• Transitive trust• No dynamic trust establishment• Use of UDP• Use of shared secrets

Connect. Communicate. Collaborateeduroam-ng

• After evaluating Diameter, RadSec and DNSROAM:

• Introduction of RadSec (if possible)– TCP instead of UDP– TLS between RADIUS-servers instead of shared secrets

• Possibly at later stage introduction of DNSROAM– Support for direct peer interaction– How about firewalls / access lists?

• Eventually Diameter?


The eduGAIN case

Exercising the confederation concepts

Connect. Communicate. CollaborateThe AAI Goal in GÉANT2

• To build an interoperable authentication and authorisation infrastructure that will be used all over Europe enabling seamless sharing of e-science resources

• We started from– Scattered AAI (pilot) implementations in the EU and

abroad– The basic idea of federating them, preserving hard-

won achievements


Applying Confederation Concepts

• An eduGAIN confederation is a loosely-coupled set of cooperating identity federations– That handle identity management, authentication and

authorization using their own policies• Trust between any two participants in different federations

is dynamically established– Members of a participant federation do not know in

advance about members in the other federations• Syntax and semantics are adapted to a common language

– Through an abstract service definition

Connect. Communicate. CollaborateThe eduGAIN Components

• Bridging Elements (BE)– Interconnection points– Federation-wide (LFA) or distributed (LA)

• Federation Peering Point (FPP)– Able to announce BE metadata

• The Metadata Service (MDS)– Publishing interface (to FPPs)– Querying interface (to BEs)

Connect. Communicate. CollaborateThe eduGAIN Model Connect. Communicate. Collaborate

Id Repository(ies)Resource(s)

MDS

R-FPP

MetadataPublish

R-BE

MetadataQuery

AAInteraction

H-FPP

MetadataPublish

H-BE

AAInteraction

AA Interaction

Connect. Communicate. CollaborateComponent Identifiers

• eduGAIN operations strongly depend on having unique, structured and well-defined component identifiers

• Based on URNs delegated by the eduGAIN registry to the participating federation

• Identifiers establish the kind of component they apply to by means of normalized prefixes

• Identifiers follow the hierarchy of the trust establishing process

Connect. Communicate. CollaborateThe (X.509) Trust Fabric

• Validation procedures include– Normal certificate validation

• Trust path evaluation, signatures, revocation,…– Peer identification

• Certificates hold the component identifier• It must match the appropriate metadata

• Applicable to– TLS connections between components

• Two-way validation is mandatory– Verification of signed XML assertions


A general model for eduGAIN interactions Connect. Communicate. Collaborate

Requester Responder

Id RepositoryResource

TLS Channel(s)

MDS

TLS Channel

https://mds.geant.net/ ?cid=someURN <EntityDescriptor . . .

entityID= ”urn:geant2:..:responder">. . .<SingleSignOnService . . . Location= “https://responder.dom/” /> . . .

<samlp:Request . . . RequestID=”e70c3e9e6…” IssueInstant=“2006-06…”> . . .</samlp:Request>

<samlp:Response . . . ResponseID=”092e50a08…” InResponseTo=“e70c3e9e…”> . . .</samlp:Response>

urn:geant2:...:responder

urn:geant2:...:requester

Connect. Communicate. CollaborateOperation Mapping

• Maps the abstract service definition into actual protocols• Current version is based on SAML 1.1

– Profiling the standard to fit abstract parameters• A SAML 2.0 implementation will be available along the

lifetime of the project– The abstract service specification protects components

and applications from these changes• Authentication assertions and attribute exchange

mechanisms are designed to be Shibboleth 1.3 compatible– And Shibboleth 2 in the future

Connect. Communicate. CollaborateMetadata Service

• Based on REST interfaces transporting SAML 2.0 metadata• Metadata are published through POST operations• Metadata are retrieved through GET operations• URLs are built as

MDSBaseURL/FederationID/entityID?queryString– Using component names– The query string transports data intended to locate the appropriate

home BE (Home Locators)• Hints provided by the user• Contents of certificate extensions

(SubjectInformationAccess)

Connect. Communicate. CollaborateeduGAIN Profiles

• Three profiles defined so far– Web SSO (Shibboleth compatible)– Automated client (no human interaction)– Non-web client (use of SASL-CA)

• Others envisaged– Extended Web SSO (allowing the send of POST data)– eduGAIN usage from roaming clients (DAMe)

• Based on SAML 1.1– Mapping to SAML 2.0 profiles along the transition period

Connect. Communicate. CollaborateA Sample Profile Connect. Communicate. Collaborate


DAMe

aka “The holy grail”


Deploying Authorization Mechanisms for Federated Services in eduroam (DAMe)

• DAME is a project that builds upon:

– eduroam, which defines an inter-NREN roaming architecture

based on AAA servers (RADIUS) and the 802.1X standard,

– Shibboleth and eduGAIN

– NAS-SAML, a network access control approach for AAA

environments, developed by the University of Murcia (Spain),

based on the SAML (Security Assertion Markup Language) and

the XACML (eXtensible Access Control Markup Language)

standards.

Connect. Communicate. CollaborateFirst Goal: extNAFirst Goal: Extension of eduroam Using NAS-SAML Connect. Communicate. Collaborate

Gast

piet@university_b.nl

RADIUS server

University B

RADIUS server

University A

SURFnet

Central RADIUS

Proxy server

Authenticator

(AP or switch) User DB

User DB

Supplicant

data

• User mobility controlled by assertions and policies expressed in SAML and XACML

XACML

Policy Decision Point

SAML

Source Attribute Authority

Signaling

Connect. Communicate. CollaborateFirst Goal: extNASecond Goal: eduGAIN as AuthN and AuthR Backend Connect. Communicate. Collaborate

• Link between the AAA servers (now acting as Service Providers) and eduGAIN

Connect. Communicate. CollaborateFirst Goal: extNAThird Goal: Universal Single Sign On Connect. Communicate. Collaborate

• Users will be authenticated once, during the network access control phase

• The eduGAIN authentication would be bootstrapped from the NAS-SAML

• New method for delivering authentication credentials and new security middleware


Summary and conclusions

Connect. Communicate. CollaborateSummary

• Educational federations are happening– And suffering their first growing pains

• Convergence to (small number of) standards– In the SAML orbit

• International confederations are emerging– eduroam– Géant2 AAI (eduGAIN)– The twain will ever meet– Using the same principles and standards

Documents

Connect. Communicate. Collaborate Federated peering the NREN way: eduGAIN and eduroam Diego R. Lopez (RedIRIS) Klaas Wierenga (SURFnet)