1. Connect. Communicate. Collaborate NTUA/GRNET Interdomain SLAs Enforcement Framework in Real QoS-Enabled Networks C. Marinos, A. Polyrakis, V. Pouli, M. Grammatikou, V. Maglaris {cmarinos, apolyr, vpouli, mary, maglaris}@netmode.ntua.gr NTUA/GRNET TNC08, Bruges, 21 May 2008

2. Connect. Communicate. Collaborate NTUA/GRNET Outline Introduction Multi-domain SLAs SLA Enforcement Framework Current work Future work

3. Connect. Communicate. Collaborate NTUA/GRNET Introduction‏ Multi-domain environment –GÉANT2, NRENs, MAN/Campus networks

4. Connect. Communicate. Collaborate NTUA/GRNET Multi-domain SLAs E2e SLA provides the technical and administrative details to perform – Maintenance – Monitoring – Troubleshooting in a multi-domain context. To define specific level of QoS across e2e paths passing through networks like GÉANT2/NRENs –Need for end-to-end network SLAs Establishment of e2e SLAs based on per-domain SLAs

5. Connect. Communicate. Collaborate NTUA/GRNET SLA: template - ALO: set of administrative-legal parameters –Contacts –Duration –Availability –Response times –Fault handling procedures - SLO: set of technical parameters –Service instance scope –Flow description –Performance guarantees –Monitoring infrastructure –Reliability guarantees: max downtime (MDT), time to repair (TTR)‏ SLA template can be divided in two objects: 1. Legal Part - Administrative Level Object (ALO) 2. Service Level Object (SLO)‏

6. Connect. Communicate. Collaborate NTUA/GRNET Merging rules for e2e SLA E2e SLA derived from the merging of the per-domain SLAs. Most of the metrics are the union of per-domain metric values. While for the e2e performance metrics apply the following rules: - C(e2e) <= min{Ci} - MTU(e2e) <= min{MTUi} - OWD(e2e) => Σ{OWDi} - IPDV(e2e) = we treat IPDV as an RMS value and use its square as an additive parameter - Packet loss: will be the sum of all the packet losses across the individual domains: PL e2e ≥ ∑{PL i }

7. Connect. Communicate. Collaborate NTUA/GRNET SLA Framework Introduce SLA Framework for automated SLA management, creation, publication in an inter-domain environment Adopted by AMPS (Advanced Multi-domain Provisioning System) of GÉANT2

8. Connect. Communicate. Collaborate NTUA/GRNET SLA Framework Architecture (1)‏ -SLA framework installed in each domain across the e2e path -Well defined APIs carry out the inter and intra domain communication -Inter: between the SLA framework of the involved domains -Intra: between intra-domain entities and the administrator responsible for the SLA management within each domain -Can be deployed in network reservation systems to provide e2e SLAs for the network reservations

9. Connect. Communicate. Collaborate NTUA/GRNET SLA Framework Architecture (2) Categorization: 3 levels - Administrative Interface: through a web interface the domain administrator can manage and configure SLA framework - SLA Communicator: responsible for the intra-domain communication of the different entities in each SLA framework. - SLA Manager: responsible for the inter-domain communication of SLA frameworks

10. Connect. Communicate. Collaborate NTUA/GRNET SLA Service Lifecycle – 3 phases 1. Creation phase 2. Publication phase 3. Delivery phase

11. Connect. Communicate. Collaborate NTUA/GRNET 1. SLA Creation phase (1) The service requests are received through the SLA Communicator by the first domain on the reservation path. They are forwarded sequentially to the rest domains in this path through the SLA Manager.

12. Connect. Communicate. Collaborate NTUA/GRNET 1. SLA Creation phase (2)‏ Each domain evaluates the network reservation request and produces the local SLA. –Fill in the corresponding Administrative Service Object and the Service Level Specification. –Store per-domain SLA in local database

13. Connect. Communicate. Collaborate NTUA/GRNET 2. SLA publication phase Each domain responds backwards through the SLA Manager to the 1 st domain in the path by sending its own SLA.

14. Connect. Communicate. Collaborate NTUA/GRNET 3. Delivery phase The first domain on the chain collects the SLAs of all the SLA Frameworks on the chain in order to produce the end-to-end SLA. The e2e SLA is stored in a database among with the per-domain SLAs and other internal data. The data can be viewed and edited via the administrative functions of the Administrative Interface. If a domain in the path does not deliver its respective SLA, the first SLA Framework informs the client that an SLA cannot be delivered for the requested IP service, so that the client can make a new request with different level of QoS.

15. Connect. Communicate. Collaborate NTUA/GRNET Current status Integration and deployment of SLA framework into AMPS(Advanced Multi-domain Provisioning System in GÉANT2)‏ –Communication of SLA module with other AMPS modules –Triggered by end-user upon service request –Provides e2e SLA calculation for user network reservation

16. Connect. Communicate. Collaborate NTUA/GRNET SLA Generation Process in AMPS 1.Administrative Interface receives notification for SLA creation for a specific AMPS reservation 2.SLA Communicator forwards the request to the single- domain module and SLA Manager to the multi-domain modules 3.Each domain generates local SLA and sends it to the SLA Manager of the previous AMPS 4.First SLA Manager collects the per-domain SLAs, generates e2e SLA, stores it to local DB and delivers it to the client

17. Connect. Communicate. Collaborate NTUA/GRNET Future work Deploy SLA framework into AMPS in various NRENs Deploy monitoring tools to: –Take measurements and evaluate the SLA Framework –Monitor the SLA guarantees

18. Connect. Communicate. Collaborate NTUA/GRNET Thank you! For more info contact: cmarinos@netmode.ntua.gr ?