Autonomic Networks Service Discovery

1. Konstantinos Oikonomou Lancaster, UK Tuesday, June 9, 2009 Autonomic NetworksService Discovery

2. Konstantinos Oikonomou Ioannis Stavrakakis NKUA Lancaster, UK Tuesday, June 9, 2009 Task 2.3

3. ANA - Project SA Example: Intermediate Node ANA Node Neighbor Nodes Neighbor Nodes • Update Local Info • Decision • e.g., forward the sa message sd sdif02 sdif01 eth1 eth0 Ethernet card Ethernet card

4. ANA - Project Implementation Reported also as part of WP4 … Previous Year: the sd, sdif bricks have been developed and tested (no bugging problems were seen)‏ This year: implementation of a number of algorithms inside the sd brick So far: advertisement and searching (backtrace process)‏ Probabilistic flooding is almost there Replicated random walkers is the next step Low-cost infrastructure and local-area dominating sets are also considered We plan to be ready by the end of September to be able to run experiments and tests to move to the latest version of the code

5. ANA - Project Conceptual Work (I)‏ Accepted/Published IEEE/ACM Transactions on Networking extended version of the IEEE Infocom 2007 paper including new material IFIP MedHocNet 2009 IEEE WoWMoM AOC Workshop 2009 IEEE PCI 2009 Submitted/progress Service migration (under review)‏ Probabilistic flooding (ready for submission)‏ Replicated random walkers (analytical model)‏ Random walkers with jumps

6. ANA - Project Conceptual Work (II)‏ New Ideas (currently under study/paper preparation): Local information dominating set approximation Low-cost structure for “directed” information dissemination messages Migration in structured environments Graduates: One undergraduate thesis Two PhD students defending until the end of this year One undergraduate thesis until the of this year

7. ANA - Project J-RW: An example Random Walker Network Jump to a different network area Visit the same area with increased probability Visit a different area withincreased probability

8. ANA - Project Ideally Stretched Information Dissemination Service Node Network

9. Task 4.2

10. ANA - Project Service Node Network

11. ANA - Project Leader election example ANA Node ANA Node ANA Node -sd replies: do not use sdif01 -no leader is found inside the network compartment -sdif takes the name sdif02 and becomes leader of the network compartment -another sdif starts -a name is required -sd will be asked as well as the leader of the compartment -sd replies that no other sdif is Registered -sdif tries to resolve the leader of its network compartment -No reply (since no leader exist right now in the compartment -sdif becomes the leader -publishes the name leader inside the network cmprtmnt -Publishes sdif01 inside the ANA Node compartment -sdif brick is inserted -It connects to the ethernet and sd -A name should be determined sd Sdif02 Leader Sdif01 Leader Name?? Name? eth1 eth0 Ethernet card Ethernet card Network Compartment Network Compartment sd sd Sdif01 Sdif01 Name?? Name?? eth0 eth1 Ethernet card Ethernet card

12. ANA - Project Demo: what we have done so far Program in C creating topologies according to well-known models Barabasi-Albert, Erdos-Renyi, grids, trees … Program in C to create scripts for automatically uploading these topologies in MINMEX NAM visualization of the topology advertisement and searching This is done inside the ANA node sd an sdif bricks service migration

13. ANA - Project Demo: Ideas? Get some input today from brainstorming and see how to adapt our plan … Possibly (using NAM) to demonstrate self-*: Show advertisement/searching of already developed algorithms (.nam file generated by bricks)‏ Show adaptive placement (migration) using .nam file generated by our simulator

14. ANA - Project SD, ANA Node and … SDFB Autonomic Placement Advertisement Searching Flexible Reusable Flexible Autonomic Reusable ANA Node (MINMEX)‏ SDFB (SD Functional Block)‏ Autonomic Flexible Reusable

15. ANA - Project Outline Development What we have achieved so far How we see it fit to proceed Receive comments on the development directions Conceptual Work Extension of Infocom 07 paper => submitted to ToN AOC 2008 – on going extension (shortly to be submitted)‏ Medhocnet 2008 – Replication of random walks in geometric graphs - (extensions for power-law, clustered, random graphs and regular topologies)‏ Random walks with jumps (on going work, shortly to be submitted)‏ Random walks with d choice (on going work)‏

16. ANA - Project Development Steps Towards SDFB Initial Steps Run MINMEX Create Topologies Specific service discovery interface: sdif brick allows for generic underlying connectivity assumptions The ethernet compartment was considered during the implementation Note: sdif works for other “network compartments” too sd brick: Receives messages from service advertisement (sa brick)‏ service searching (ss brick)‏ the underlying sdif bricks … Implements the protocol/algorithm (e.g., update local info and forward messages)‏ Note: any distributed (asynchronous) algorithm may be implement!! Not specific to service discovery (e.g., routing) => Reusability Forwards messages according to the implemented protocol/algorithm sa/ss brick: Triggers a service advertisement/searching phase

17. ANA - Project SA Example I ANA Node Neighbor Nodes sa sa brick sd sd brick sdif01 sdif brick eth0 eth brick Ethernet card

18. ANA - Project SA Example II ANA Node Neighbor Nodes Neighbor Nodes • Update Local Info • Forward sa message sd sdif02 sdif01 eth1 eth0 Ethernet card Ethernet card

19. ANA - Project SA Example II ANA Node Neighbor Nodes Neighbor Nodes • Update Local Info • Forward sa message sd sdif02 sdif01 eth1 eth0 Ethernet card Ethernet card

20. ANA - Project SS Example I ANA Node Neighbor Nodes ss ss brick sd sdif01 • Check Local Info • Send back reply if any • Forward ss message eth0 Ethernet card

21. ANA - Project SS Example I ANA Node Neighbor Nodes ss ss brick sd sdif01 • Check Local Info • Send back reply if any • Forward ss message eth0 Ethernet card

22. ANA - Project SS Example II ANA Node Neighbor Nodes Neighbor Nodes • Check Local Info • Send back reply if any • Forward ss message sd sdif02 sdif01 eth1 eth0 Ethernet card Ethernet card

23. ANA - Project SS Example II ANA Node Neighbor Nodes Neighbor Nodes • Check Local Info • Send back reply if any • Forward ss message sd sdif02 sdif01 eth1 eth0 Ethernet card Ethernet card

24. ANA - Project Publishing in Compartments The basic idea is to let the sd brick be as simple as possible and let sdif brick deal with all details (such as publishing names) that are not part of the protocol/algorithm to be implemented The name inside the compartment (e.g., eth0 inside ANA Node) should be unique An sdif brick: Publishes its name (e.g., sdif01) to the ANA Node Compartment Publishes the same name (?) to the network compartment (in our case the ethernet compartment)‏ It should be made sure that no othersdif brick has the same name in both compartments (ANA Node and the network compartment)‏ Difficult to ensure this uniqueness of names Solution followed (to ensure the autonomic/distributed nature of the approach): Let each sd brick maintain information about the sdif names inside the particular ANA Node Elect a sdif leader for each network compartment to Communicate with the particular sd brick and receives information about the existing names Check its own list of allocated names inside the network compartment Decide a new name for the sdif brick Update its own list of allocated names and inform the corresponded sd brick Take care when a leader breaks down (robustness)‏

25. ANA - Project Some Development Details Note that a sdif brick that is a leader publishes “leader” inside the network compartment and “sdifxx” inside the ANA Node compartment That saves on name for future allocation Names range from sdif01 to sdif99 Easy to increase the range of values When a leader shuts down another one is elected and assumes responsibility The one with the smallest interface number Numerous failure scenarios may be detected We believe we have dealt with the most important ones Nice for future studies of robustness, failure detection etc. System crash behavior: If a brick (sdif, sd, sa, ss) exits normally (i.e., brick_exit() is called)‏ no need to initialize the SDFB MINMEX still operational (no need to initialize the system)‏ If a brick does not exit normally (e.g., segmentation fault, power failure) we relay on MINMEX to maintain the stability of the overall system However, no segmentation fault was experienced after many tests (never safe to say that there is no bug in the program)‏ Difficult to test cases of power failure

26. ANA - Project What has been achieved? We have “moved” much functionality to the sdif brick in order to allow the sd brick to remain as simple as possible Overall, we can claim that our development is characterized by Autonomicity In the implementation (due to the non-layer notion and the adoption of the “brick” idea)‏ In the algorithms different SD policies for different services SD policies changing on the fly Fully distributed approach (no centralized entity)‏ Entering, leaving and moving nodes do not affect the underlying “system” Flexibility Easy to implement algorithms Do not have to worry about the ANA Node specifics Protocol implementation takes place only in the sd brick No need to know details about the particulars of sdif brick Easy to “import” existing algorithms Reusability Easy to be used by other partners Easy to import existing (or future!) implementations

27. ANA - Project Development: Overall and Future Plans So far we see ourselves at the end of our “prototype” phase so, we need to reconsider (design) before moving on (further implementation)‏ Until the end of this year (Panagiotis’ thesis)‏ Move to the latest ANA Node version Design and Specification Incorporate a easy-to-work-with state machine mechanism will further simplify protocol implementation Next year Start implementing the SD algorithm/protocol (Panagiotis’ thesis)‏ We will also try to implement service placement Implement other algorithms (e.g., routing) (student thesis)‏