Grid Services Overview & Introduction Ian Foster Argonne National Laboratory University of Chicago Univa Corporation OOSTech, Baltimore, October 26, 2005

2 What’s This About “Grid Services”? l I will describe Web service interfaces that implement useful behaviors u Primitives: resources, state, security u Services: program execution, data movement, data access, … l I will also describe open source software that implements those interfaces u In particular, Globus Toolkit (GT4) l This is all standard Web services! u “Grid is a use case for Web services, focused on resource management”

3 R R R R R R R R R R What Grid is About: Aggregation in Virtual Organizations Distributed resources and people Linked by networks, crossing admin domains Sharing resources, common goals Dynamic behaviors VO-B VO-A R R R R

4 R R R R R R R R R R R R VO-B Distributed resources and people Linked by networks, crossing admin domains Sharing resources, common goals Dynamic behaviors Fault tolerant What Grid is About: Aggregation in Virtual Organizations

5 Grid Technology: Take Services Seriously l Model the world as a collection of services u Computations, computers, instruments, storage, data, communities, agreements, … l Focus on what these things have in common u E.g., state modeling & lifecycle: Negotiation, deployment/creation, modeling, monitoring, management, termination u E.g., security: Authentication, authorization, audit, …  Result is Grid infrastructure u Using Web services as a platform

6 “Stateless” vs. “Stateful” Services l Without state, how does client: u Determine what happened (success/failure)? u Find out how many files completed? u Receive updates when interesting events arise? u Terminate a request? l Few useful services are truly “stateless”, but WS interfaces alone do not provide built-in support for state Client FileTransfer Service move (A to B) move

7 FileTransferService (without WSRF) l Developer reinvents wheel for each new service u Custom management and identification of state: transferID u Custom operations to inspect state synchronously (whatHappen) and asynchronously (tellMeWhen) u Custom lifetime operation (cancel) Client FileTransfer Service move (A to B) : transferID move state whatHappen tellMeWhen cancel

8 WSRF in a Nutshell l Service l State representation u Resource u Resource Property l State identification u Endpoint Reference l State Interfaces u GetRP, QueryRPs, GetMultipleRPs, SetRP l Lifetime Interfaces u SetTerminationTime u ImmediateDestruction l Notification Interfaces u Subscribe u Notify l ServiceGroups RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR

9 FileTransferService (w/ WSRF) l Developer specifies custom method to createResource and leaves the rest to WSRF standards: u State exposed as Resource + Resource Properties and identified by Endpoint Reference (EPR) u State inspected by standard interfaces (GetRP, QueryRPs) u Lifetime management by standard interfaces (Destroy) Client FileTransferService createResource (A to B) : EPR createResource RPs Transfer getRP queryRPs destroy

10 Grid Infrastructure: Open Standards Web services (WSDL, SOAP, WS-Security, WS-ReliableMessaging, …) WS-Resource Framework & WS-Notification* (Resource identity, lifetime, inspection, subscription, …) WS-Agreement (Agreement negotiation) WS Distributed Management (Lifecycle, monitoring, …) Applications of the framework (Compute, network, storage provisioning, job reservation & submission, data management, application service QoS, …) *WS-Transfer, WS-Enumeration, WS-Eventing, WS-Management define similar functions

11 Data Mgmt Security Common Runtime Execution Mgmt Info Services GridFTP Authentication Authorization Reliable File Transfer Data Access & Integration Grid Resource Allocation & Management Index Community Authorization Data Replication Community Scheduling Framework Delegation Replica Location Trigger Java Runtime C Runtime Python Runtime WebMDS Workspace Management Grid Telecontrol Protocol Globus Toolkit v4 Credential Mgmt Globus Toolkit: Open Source Grid Infrastructure Tools for building WSRF services

12 GT4 WS Core in a Nutshell RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR Implementation of WSRF: Resources, EndpointReferences, ResourceProperties Operation Providers: pre-build implementations of WSRF operations Notification implementation: Topics, TopicSet, Embedded Notification Consumer service Implementations of Resources (ReflectionResource, PersistentReflectionResource) and ResourceProperties (SimpleResourceProperty, ReflectionResourceProperty)

13 GT4 WS Core in a Nutshell RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR ResourceHome ResourceHome: The home “owns” the Resource instances in the service SingletonResourceHome: manages single instance of Resource ServiceResourceHome: for services that support a single Resource instance ResourceHomeImpl: manages multiple Resource instances. Supports resources with in- memory state and resources with persistent (on disk) state

14 Service Container GT4 WS Core in a Nutshell RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR ResourceHome RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR ResourceHome RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR ResourceHome Service Container: host multiple services in container; one JVM process …more details: based on AXIS service container, processes SOAP messages, ResourceContext extension.

15 Service Container GT4 WS Core in a Nutshell RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR ResourceHome RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR ResourceHome RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR ResourceHome Secure Communication: Transport, Message, Conversation (Transport demonstrates best performance) PIP PDP Configurable Security Policies: Policy Information Points (PIPs), Policy Decision Points (PDP) -- chained Example authorization PDPs: GridMap, SAML implementations, XACML policies

16 Service Container GT4 WS Core in a Nutshell RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR ResourceHome RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR ResourceHome RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR ResourceHome PIP PDP WorkManagerDB Conn Pool JNDI Directory WorkManager: “thread pool”, site independent “work” manager Apache Database Connection Pool library (JDBC “DataSource” implementation) JNDI Directory: manages internal, shared objects (ResourceHomes, WorkManager, Configuration objects,…)

17 Apache Tomcat Service Container GT4 WS Core in a Nutshell RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR ResourceHome RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR ResourceHome RPs Resource Service GetRP GetMultRPs SetRP QueryRPs Subscribe SetTermTime Destroy EPR ResourceHome PIP PDP WorkManagerDB Conn Pool JNDI Directory Deploy Service Container “standalone” or within Apache Tomcat

18 Data Mgmt Security Common Runtime Execution Mgmt Info Services GridFTP Authentication Authorization Reliable File Transfer Data Access & Integration Grid Resource Allocation & Management Index Community Authorization Data Replication Community Scheduling Framework Delegation Replica Location Trigger Java Runtime C Runtime Python Runtime WebMDS Workspace Management Grid Telecontrol Protocol Globus Toolkit v4 Credential Mgmt Globus Toolkit: Open Source Grid Infrastructure

19 GT4 Security l Public-key-based authentication l Extensible authorization framework based on Web services standards u SAML-based authorization callout l As specified in GGF OGSA-Authz WG u Integrated policy decision engine l XACML policy language, per-operation policies, pluggable l Credential management service u MyProxy (One time password support) l Community Authorization Service l Standalone delegation service

20 GT4 Use of Security Standards Supported, Supported, Fastest, but slow but insecure so default

21 GT-XACML Integration l eXtensible Access Control Markup Language u OASIS standard, open source implementations l XACML: sophisticated policy language l Globus Toolkit ships with XACML runtime u Included in every client and server built on GT u Turned-on through configuration l … that can be called transparently from runtime and/or explicitly from application … l … and we use the XACML-”model” for our Authz Processing Framework

22 Data Mgmt Security Common Runtime Execution Mgmt Info Services GridFTP Authentication Authorization Reliable File Transfer Data Access & Integration Grid Resource Allocation & Management Index Community Authorization Data Replication Community Scheduling Framework Delegation Replica Location Trigger Java Runtime C Runtime Python Runtime WebMDS Workspace Management Grid Telecontrol Protocol Globus Toolkit v4 Credential Mgmt I. Foster, Globus Toolkit Version 4: Software for Service-Oriented Systems, LNCS 3779, 2-13, 2005 Globus Toolkit: Open Source Grid Infrastructure

23 Managing Computers & Computation l GRAM (Grid Resource Allocation & Management) service u Negotiate access u Stage code u Monitor service u Manage service u Collect accounting data l Can negotiate access to clusters, creation of virtual machines, establishment of virtual networks, … GRAM Client

24 CMS DC04 ATLAS DC2 Usage: CPUs Dynamic Provisioning of Computational Services Open Science Grid use over 6 months

25 Dynamic Service Deployment Community A Community Z … Community scheduling logic Data distribution Community management Science services PlanetLab nodes... Requirements: Community control Persistence Resource guarantees Non- interference

26 Data Mgmt Security Common Runtime Execution Mgmt Info Services GridFTP Authentication Authorization Reliable File Transfer Data Access & Integration Grid Resource Allocation & Management Index Community Authorization Data Replication Community Scheduling Framework Delegation Replica Location Trigger Java Runtime C Runtime Python Runtime WebMDS Workspace Management Grid Telecontrol Protocol Globus Toolkit v4 Credential Mgmt Globus Toolkit: Open Source Grid Infrastructure

27 Managing Storage & Data l Service interfaces for managing storage & data movement u Storage management (SRM, NeST) u Data movement (GridFTP, RFT) u Replica management (RLS, DRS) l Service interfaces for accessing data in diverse formats u OGSA Data Access & Integration u GridFTP data access & movement

28 GridFTP in GT4 l 100% Globus code u No licensing issues u Stable, extensible l IPv6 Support l XIO for different transports l Striping  multi-Gb/sec wide area transport u 27 Gbit/s on 30 Gbit/s link l Pluggable u Front-end: e.g., future WS control channel u Back-end: e.g., HPSS, cluster file systems u Transfer: e.g., UDP, NetBLT transport Disk-to-disk on TeraGrid

29 Reliable File Transfer: Third Party Transfer RFT Service RFT Client SOAP Messages Notifications (Optional) Data Channel Protocol Interpreter Master DSI Data Channel Slave DSI IPC Receiver IPC Link Master DSI Protocol Interpreter Data Channel IPC Receiver Slave DSI Data Channel IPC Link GridFTP Server l Fire-and-forget transfer l Web services interface l Many files & directories l Integrated failure recovery l Has transferred 900K files

30 Replica Location Service l Identify location of files via logical to physical name map l Distributed indexing of names, fault tolerant update protocols l GT4 version scalable & stable l Managing ~40 million files across ~10 sites Index Local DB Update send (secs) Bloom filter (secs) Bloom filter (bits) 10K<121 M M 5 M M

31  Cardiff AEI/Golm Birmingham Reliable Wide Area Data Replication Replicating >1 Terabyte/day to 8 sites >30 million replicas so far MTBF = 1 month LIGO Gravitational Wave Observatory

32 Data Replication Service: An Example of Service Composition At requesting site, deploy: l WSRF services u Data Replication Service u Delegation Service u Reliable File Transfer Service l Pre-WSRF components u Replica Location Service (Local Replica Catalog and Replica Location Index) u GridFTP Server

33 Data Replication Service: WSDL (PortType) … … … … … … … … … … … …

34 Data Replication Service: WSDL (Resource Properties) … … … … … … … … … … … … … …

35 Data Mgmt Security Common Runtime Execution Mgmt Info Services GridFTP Authentication Authorization Reliable File Transfer Data Access & Integration Grid Resource Allocation & Management Index Community Authorization Data Replication Community Scheduling Framework Delegation Replica Location Trigger Java Runtime C Runtime Python Runtime WebMDS Workspace Management Grid Telecontrol Protocol Globus Toolkit v4 Credential Mgmt Globus Toolkit: Open Source Grid Infrastructure

36 GT4 Container GT4 Monitoring & Discovery GRAMUser MDS- Index GT4 Cont. RFT MDS- Index GT4 Container MDS- Index GridFTP adapter Registration & WSRF/WSN Access Custom protocols for non-WSRF entities Clients (e.g., WebMDS) Automated registration in container WS-ServiceGroup

37 Summary l Services are typically stateful, but WS standards did not support stateful entities l WSRF provides standards for management, identification, lifetime, inspection, & manipulation of stateful entities l GT4 WS Core provides a rich environment for developing stateful services l GT4 provides a rich set of services based on WSRF & WS-Notification

38 For More Information l Globus Alliance u l Global Grid Forum u l Background information u 2nd Edition