Authentication Authorization Accounting and Auditing Open Issues for

Authentication Authorization Accounting and Auditing Open Issues for irtf AAAARCH working group IWS 2000 February 16, 2000 John Vollbrecht Director, Merit AAA Server Consortium [email protected] edu Merit Network Inc.

AAARCH irtf working group– goals and objectives • Research rather than engineering group – Long term architecture group, related to AAA working group • Architecture and models for AAA/A in 9 -12 months • Feed full requirements to AAA wg in early 2001 As opposed to • AAA ietf wg goals – • to have an “interim” protocol requirements by end of March (Adelaide ietf) • Hope to recharter as a Protocol selection group and have interim protocol by early 2001 [email protected] edu IWS 2000 !6 Feb. 2000

AAA infrastructure – vision for the future User org AAA Appl with AAA Broker AAA Broker User org AAA User Appl with AAA [email protected] edu IWS 2000 !6 Feb. 2000

AAA irtf basic concepts • Focus on inter-organization issue • Service provider and user-organization each “own” policy • Push, Pull, Agent sequences for Authorization • Brokers and Proxies as intermediaries between service providers and userorganizations [email protected] edu IWS 2000 !6 Feb. 2000

Brokers and Proxies • Different types of intermediaries • Brokers aggregate applications and/or “user-orgs” – Facilitate inter-organization cooperation • Proxies promote interaction between AAA servers within an administrative domain – Often translate between organization specific and standard interface • Much of AAA work deals with how Brokers and Proxies fit with AAA protocols [email protected] edu IWS 2000 !6 Feb. 2000

Brokers and Proxies – Requirementstentative definitions • Brokers have business relationship with multiple organizations – Implies enough trust to do business – Perhaps not “complete” trust – Requires audit friendly AAA system • Proxies interact with AAA servers in the same organization – Implies organizational trust (not network/security trust) – Typically uses • translate between AAA protocols • aggregate AAA servers in an organization • Interface to AAA servers in other organizations [email protected] edu IWS 2000 !6 Feb. 2000

AAAARCH –Open Issues • • • Data representation Data security Interaction between accounting and authorization State maintenance with no single point of failure Distributed policy – Storage/ evaluation/ enforcement – Policy description • Auditing requirements [email protected] edu IWS 2000 !6 Feb. 2000

Data Representation • • • Groups of objects Groups of groups Integrity by group Identify originating and destination server(s) Data Object contents could be – Policy description – Policy “data” – Policy evaluation • Possibly Self defining syntax for objects jrv. [email protected] edu IWS 2000 !6 Feb. 2000

Data Objects (DO 1) (AAA-HDR) Service AAA (DO 1) (DO 2)(AAA-HDR) Broker AAA (AAA-HDR)(DO 3)(DO 4) User-org AAA (AAA-HDR)(DO 3)

Data Object Security • Integrity – Role of mac vs. signatures – Role of intermediary • Broker • Trusted 3 rd party – Performance and business model [email protected] edu IWS 2000 !6 Feb. 2000

Data Object Security • Confidentiality – When is it required • Examples – Clear text password – Session key for FA/HA in Mobile. IP – What is required • Some external authority trusted by originator and receiver of confidential data object [email protected] edu IWS 2000 !6 Feb. 2000

Accounting and Authorization • Authorization can include Accounting Policy • Accounting to demonstrate that requested policy was implemented ( i. e. that QOS requested was delivered) • Requirement for a “session id” to identify Accounting and Authorization activity for the same session [email protected] edu IWS 2000 !6 Feb. 2000

State Maintenance • State is what is known about a session – often most important is whether the session is currently “up” • Information about state of session may be maintained in multiple AAA servers • There is one source of authoritative information about each state element of the session • Making sure that what is kept in AAA server matches authoritative source is tricky and has led to systems with difficulty doing fail over between a primary and backup server [email protected] edu IWS 2000 !6 Feb. 2000

Distributed Session State (proposal) Request/reply State request Primary AAA Server NAS State update Backup AAA Server Sess state [email protected] edu IWS 2000 !6 Feb. 2000

Distributed Policy • Policy Description – Repository maintained by organizational owner • Policy Data – Data to be evaluated by policy • Policy Enforcement – Doing what the Policy describes • Owner of policy may not be owner of Policy Data • Enforcement of Policy decision may be by different organization than the one defining policy [email protected] edu IWS 2000 !6 Feb. 2000

Distributed Policy Repository User-org AAA User info db Broker AAA Policy Repository Broker agreements db Application AAA Device PEP Policy Repository Application state db

Auditing • With multi-organization process, each organization must trust that others are doing what is expected • Auditing verifies that processes are reasonable, appropriate for expected results • Equivalent to what CPA would require for standard business systems • Expands network management to multiorganization process [email protected] edu IWS 2000 !6 Feb. 2000

Some Audit Mechanisms • Logging signed requests and session status records • Logging by trusted 3 rd party of appropriate records • Real time “check” that appropriate programs are running • Comparing log entries from cooperating servers [email protected] edu IWS 2000 !6 Feb. 2000

Summary • Active Group working on AAA issues • Goal is to find and define a simple mechanism that permits complex services • Open mail group • We encourage interested people to join the group (mail to [email protected] edu or [email protected] uu. nl) • Questions/ comments? (Thanks)