OMAC: Optimal Migration Algorithm for Virtual CDN. Hatem Ibn Khedher, Emad ABD-ELRAHMAN, Hossam AFIFI RST Dept., Inst. Mines-Telecom, Saclay, France

Transcription

1 OMAC: Optimal Migration Algorithm for Virtual CDN Hatem Ibn Khedher, Emad ABD-ELRAHMAN, Hossam AFIFI RST Dept., Inst. Mines-Telecom, Saclay, France 1

2 Presentation Outline Introduction Network issues in vcdn migration Architecture of vcdn deployment Exact optimization of vcdn deployment Conclusion 2

3 Presentation Outline Introduction Network issues in vcdn migration Architecture of vcdn deployment Exact optimization of vcdn deployment Conclusion 3

4 Virtualization? Def. By ETSI ETSI, the European Telecommunications Standards Institute Servers Storage (SANs) Switches 1. Compute virtualization 2. Storage virtualization 3. Network virtualization 4

5 Virtualization context: architecture General virtualization architecture The proposed architecture

6 Virtualization context Deployment techniques of network functions (NF) are hardwarization and softwarization. Hardwarization means coupling the NF to the hardware. It is justified by: Computation efficiency Energy savings Softwarization is the opposite, (i.e., virtualization). Minimum efforts needed for development Minimum cost of deployment, load balancing Flexibility, elasticity, and easy upgrade of virtual network functions (e.g., CDN, DPI, P/S-GW, etc ) 6

7 Target network function CDN Content Delivery Network that hosts the video contents to be closer to the client group nodes CDN Controller vcdn The software that virtualized the CDN caching and streaming services on NFV servers using SDN/NFV concepts. 7

8 How to virtualize? ETSI standard: NFV proposal for virtualization 8

9 NFV Building Block 2. VNF 1. NFV MANO vcdn vfw vdpi vrouter 3. NFVI S/W VMs H/W 9

10 Software-Defined Networking (SDN) ONF standard: SDN proposal for virtualization 10

11 An SDN-NFV Interaction Control Control Protocols: OpenFlow off-the-shelf equipment Data Opendaylight SDNi OpenFlow Data OpenStack NFVI 11

12 Virtualized reference architecture Hypervisor-1 Migration Hypervisor-2 eth0 vnet0 vcdn br0 OVS vcdn eth0 vnet1 eth0 GRE VXLAN eth0 vnet0 vcdn vcdn eth0 br0 OVS eth0 vnet1 H/W H/W Physical Link 12

13 Presentation Outline Introduction Network issues in vcdn migration Architecture of vcdn deployment Exact Optimization of vcdn deployment Conclusion 13

14 Live migration of vcdn Live Migration Definition: Transfer a vcdn node from one host to another without disrupting services. vcdn state: File system: which represent the Cache/storage. (typically, it is located on a NFS and is not moved) RAM pages: is transferred in the background wile the VNF still running.

15 Scenarios of Live vcdn Migration Live vcdn migration has two scenarios: with shared storage area network (SAN)

16 Scenarios of Live vcdn Migration - without shared storage area network (SAN) H. Ibn khedher et al. Network issues in Virtual machine migration ISNCC 2015

17 Network Constraints in Virtualization Tools 1) KVM: Hypervisor, Accelerator 2) Libvirt: Daemon, network manager Requirements 1. Security over SSH 2. Live Migration with shared storage (LAN Migration) 3. Live Migration with disk/network connection transfert (WAN Migration) 17

18 Network Constraints in Virtualization The main three constraints in the virtualization process are: QoS: The virtualization process consume in its transient state a huge amount of resources. Instantiation or migration of a VNF requires very high speed link.

19 Network Constraints in Virtualization Mobility: Mobility of virtual instances is not a simple task. We can consider moving an NF or a complete instance of a server depending on the desired controller objective. Moving functionality is required when we want to create a new service in a different location VNF can migrate within the same subnet or from one subnet toanother (across different LANs).

20 Network Constraints in Virtualization Security: Security is an important aspect in VNFs migrations. Many attacks could stop the live or offloading migration at any point. So, securing this migration either in single domain or inter multiple domains is mandatory.

21 Network Issues for VNF Migration

22 vcdn Migration

23 NFV-based solution How to deploy vcdn? 23

24 SDN-based solution How to deploy vcdn? 24

25 How to deploy vcdn? NFV/SDN-based solution 25

26 Presentation Outline Introduction Network issues in vcdn migration Architecture of vcdn deployment Exact optimization of vcdn deployment Conclusion 26

27 General Architecture Content providers Network operator Point of Presence Network operator Set Top Box End user group 27

28 An Example: from Physical CDN to vcdn Current solution Content providers/ CDN providers => Physical deployment of CDN Box POP - Quality - Efficiency Network operators: -Owner of the network infrastructure Box POP POP Box 28

29 An Example: from Physical CDN to vcdn within NO The proposed solution Box Box POP Content providers/ CDN providers => virtual deployment CDNs Management plan creation Network operators: Owner of the network infrastructure server deployment in the equipment of the network infra POP POP Box 29

30 Presentation Outline Introduction Network issues in vcdn migration Architecture of vcdn deployment Exact optimization of vcdn deployment Conclusion 30

31 Optimization problematic Problématique The problem considers delivering on-demand videos or services through vcdn functions. The statement is: Factors of complexity 1. Where to locate the vcdn streaming headend? 2. How to migrate vcdn node from one location to the optimal one 3. How to guarantee the requested QoE? 4. How to minimize the migration cost? 31

32 Optimization contribution A cost efficient optimization algorithm for vcdn migration under the previous complex factors. vcdn Migration to the optimal location Complementarity: Operator cost Client group demand (QoE) Exact optimization solution Feasible, flexible, and robust It enables vcdn migration inside a network operator 32

33 Optimization taxonomy (SOTA) Approaches of SDN/NFV optimization Based on Optimal algorithm 1. Simple system 2. Exact and efficient 3. Problem of Scalability 4. VNF context Non-optimal algorithm 1. Complex system 2. Near optimal 3. Large scale 4. VM context 33

34 Proposed Approach vcdn based SDN /NFV Novel approach for virtualization The proposed approach Exact algorithm Multi-criteria Yes, VNF context (vcdn), optimal Migration cost, NFV cost, QoE vcdn Migration Under different scenarios 34

35 You need to have the initial topology 35

36 How optimizations look like? Objective Function 36 36

37 Optimization model Decision about: 1. Where to migrate vcdn based on minimizing the total migration cost (operator cost). 2. Whether client group need a vcdn streaming service or not. 3. Whether the link is used for a streaming of vcdn or not. 37

38 How constraints look like? 1. On optimal server streaming the vcdn f to the client group v Constraints 2. Server caching capacity constraint 3. Server streaming capacity constraint 4. Link capacity constraint 5. Network flow constraint (flow balance) 38

39 SDN/NFV migration optimization algorithm Inputs: 1. The list of vcdn(s) to be installed, including system and network requirements 2. Places where computational resources are available 3. SDN/NFV criteria and constraints 4. The list of client group request for different vcdns Output: 1. Decide the optimal SDN/NFV Migration of vcdn (place) and the optimal routing path of vcdn streaming 39

40 Novel metrics Migration cost: The total cost of migration vcdns Migration time: The needed time for migration vcache utilization: The cost of vcdn system resources vstream utilization: The cost of vcdn network resources Link utilization: The cost of network links resources. vcdn replication number: The number of vcdns after migration 40

41 How to compile, execute, decide The optimization fits with the branch and bound algorithm, and it is NP-Hard problem Our proposed algorithm is evaluated through an Objective Programming Language (OPL) implementation and the linear solver CPLEX Results were conducted in terms of the previous indicators and metrics 41

42 How to decide? OTT/CP vcdn Request CDN Brokers vcdn Deploy Update OMAC/HPAC Mapper vcdn DBi Update vcdn Metrics System Metrics Network Metrics Initial DB Status DB vcdn Optimal Place vcdn DBs Update KVM H/W 42

43 Optimization results Impact of vcdn number on migration time, migration cost. 43

44 Optimization results Impact of vcdn number on NFV Infrastructure. 44

45 Optimization results Novel results of the impact of client group on migration time, migration cost, and NFVI domain 45

46 Optimization results Scenarios of OMAC-based vcdn migration Strict replication Loose replication vcdn migration process is bounded Unbounded vcdn migration process We evaluated the proposed OMAC under these scenarios 46

47 Optimization results Total migration cost behavior under the different scenario: strict vs. loose 47

48 Optimization results vcdn Replication number behavior in Loose scenario 48

49 How operator gain looks? H. ibn khedher et al. OPAC: Optimal Placement Algorithm for virtual vcdn computer networks under review 49

50 How algorithm outperforms? H. Ibn Khedher et al. OPAC: Optimal Placement Algorithm for virtual vcdn computer networks under review 50

51 How algorithm works: a snapshot topology H. Ibn Khedher et al. OPAC: Optimal Placement Algorithm for virtual vcdn computer networks under review 51

52 How algorithm works: a real example H. Ibn Khedher et al. OPAC: Optimal Placement Algorithm for virtual vcdn computer networks under review 52

53 Presentation Outline Introduction From CDN to virtual CDN (vcdn) Network issues in vcdn migration Architecture of vcdn deployment Exact optimization of vcdn deployment Conclusion 53

54 Conclusions In these two papers: we surveyed some technical challenges related to the virtualization techniques. Through the virtualization techniques, there are different issues either concerning hardware or network and software. Novel architectural concept for vcdn based on SDN/NFV OMAC: Intelligent migration algorithm of vcdn based on novel NFV criteria Different OMAC scenarios. 54

55 Future work Short-term Long-term The integration of OMAC in a vcdn framework Heuristic optimization of vcdn deployment Comparison Exact versus Heuristic ICN approach Integration of the OMAC-based optimization algorithm with Orange Platform under (DVD2C Project): labs.fr/public dvd2c/ 55

56 Publications Conferences: Hatem Ibn Khedher et al. Network Issues in Virtual Machine Migration in IEEE- ISNCC 2015 Hatem Ibn Khedher et al. OMAC: Optimal Migration Algorithm for virtual CDN in IEEE-ICT 2016 Journal: Hatem Ibn Khedher et al. OPAC: Optimal Placement Algorithm for virtual vcdn computer networks under review 56

57 Thank you Questions? 57