1. All Rights Reserved © Alcatel-Lucent 2009 Enhancing Dynamic Cloud-based Services using Network Virtualization F. Hao, T.V. Lakshman, Sarit Mukherjee, H. Song Bell Labs

2. All Rights Reserved © Alcatel-Lucent 2009 2 Dynamic Cloud-based Services: An Example VM Data Center 1 Data Center 2 Data Center 3 Users will leverage cloud computing services to outsource their computing needs Thin client/Virtual desktop Proxy for handheld devices Cloud Service Providers will Create a VM for the service Allocate VM closest to user User attaches to cloud to get service Cloud service provider creates VM to serve user

3. All Rights Reserved © Alcatel-Lucent 2009 3 Dynamic Cloud-based Services: An Example VM As the user population for a service changes, the best location for the VM changes Cloud Service Providers should Migrate the VM to the new location closest to the user VM migration over a LAN is supported by most virtualization software Data Center 1 Data Center 2 Data Center 3 User attaches to cloud from a different location VM should be moved to Data Center 2 Migrate VM across WAN in an efficient manner without losing service continuity VM

4. All Rights Reserved © Alcatel-Lucent 2009 4 Benefits of migration of VM across multiple networks/data centers For Cloud Service Provider Service migration across data centers Load balancing within and across data centers Performance optimization Green computing For Cloud Users Faster access Efficient data delivery

5. All Rights Reserved © Alcatel-Lucent 2009 5 All traffic anchored at home agent Triangular routing increase delay and burdens the network Fine for end user device with low traffic volume, but not for servers MIPv6 requires correspondent nodes to support MIP Transition from IPv4 to IPv6?? End users will be mixture of IPv4 and IPv6 clients Why Mobile IP is not a good solution VM 1 HA All traffic goes through the anchor point User 1 VM 2 User 2

6. All Rights Reserved © Alcatel-Lucent 2009 6 All traffic anchored at home agent Triangular routing increase delay and burdens the network Fine for end user device with low traffic volume, but not for servers MIPv6 requires correspondent nodes to support MIP Transition from IPv4 to IPv6?? End users will be mixture of IPv4 and IPv6 clients Why Mobile IP is not a good solution VM 2 VM 1 HA All traffic goes through the anchor point User 1 User 2

7. All Rights Reserved © Alcatel-Lucent 2009 7 Our Approach: Virtually Clustered Open Router (VICTOR) Traditional virtualization approach Slice and isolate resources in a physical router Each slice acts as a different router Virtually Clustered Open Router (VICTOR) Logically combine multiple physical devices to form a virtual router A physical device mimics a virtual line card with multiple virtual ports Virtual line cards are interconnected to mimic a virtual backplane Dedicated facilities (e.g.,for data centers of a cloud service provider) MPLS bandwidth-guaranteed paths Tunnels through the public Internet Virtual router with distributed forwarding elements managed by logically centralized controller Similar in concept to [SoftRouter/Openflow/RCP/4D]

8. All Rights Reserved © Alcatel-Lucent 2009 8 VICTOR Architecture FE is the first layer-3 access and aggregation point for mobile VM Forwarding Element (FE) Handles all data plane functions Sets up a virtual backplane between each other as necessary Can be distributed across WAN A data forwarding device or a VICTOR enabled router Centralized Controller (CC) Controls routing and signaling for mobile VM IP prefixes Computes and installs forwarding table for each FE Acts as a loosely coupled router with FEs as line cards, and CCs as control plane

9. All Rights Reserved © Alcatel-Lucent 2009 9 Routing in VICTOR External Routing Each FE advertises all the mobile VM addresses that VICTOR handles FE or CC calculates and maintains the best routes to the external IP addresses FE does not announce FE-FE links to external routers packets for non-mobile VMs are not routed by VICTOR Internal Routing An active VM discovers an adjacent FE and registers itself with it The FE forwards the binding to the CC The CC authenticates the binding and configures all the other FEs with the binding Only one active binding for each VM is allowed at a time Binding changes when the VM moves to another FE Each FE maintains a forwarding table local bindings for locally registered VMs foreign bindings for remotely registered VMs

10. All Rights Reserved © Alcatel-Lucent 2009 10 Packet Forwarding in VICTOR VM 2 VM 1 External Packet Forwarding FE receives a packet destined to an external IP address Packet is directly sent out by looking up external forwarding table Internal Packet Forwarding FE receives a packet destined to a VM Tunnel header, if any, is stripped off Packets for VM with local binding are directly forwarded Packets for VM with foreign binding are forwarded to the current FE Packet discarded if no binding is found

11. All Rights Reserved © Alcatel-Lucent 2009 11 VM Migration across Data Centers 1)VM sends an ARP 2)Local FE receives the ARP and sends the message to CC 3)CC installs new routing entry in local FE for the VM 4)CC installs new routing entry in the old FE VM 1 2 3 4 Data Center 1 Data Center 2 Data Center 3 Old location New location Mobile VMs must have IP addresses that do not conflict with any other hosts in the cloud VMs with destination NAT-ed addresses are moved by allocating non-conflicting private addresses to the mobile VMs VM migration within a data center is similar in principle but simpler

12. All Rights Reserved © Alcatel-Lucent 2009 12 Experimental Prototype of VICTOR Prototype based on Linux (FC 9) All FEs are controlled by CC FE 2 and FE 3 have 4-port NetFPGA GbE card Developed new Openflow controller to support Mobile node registration Layer 3 routing VM Migration VM migrated from Server 1 to Server 2 Ping VM from Server 3 at 0.01 sec interval Packet loss = 350 3.5 sec connectivity interruption Same downtime over LAN migration negligible overhead Physical Host Migration Mobile PC changed attachment from AP 1 to AP 2 Ping mobile PC from Server 3 at 0.01 sec interval Packet loss = 12 0.010.02 sec connectivity interruption Forwarding Table at FE 2 FlowAction nw_dst=10.2.3.1mod_dl_dst,out:2 nw_dst=10.10.0.11mod_dl_dst,out:2 nw_dst=10.10.0.36mod_dl_dst,out:3 nw_dst=10.4.5.1out:0 nw_dst=10.6.7.1out:1

13. All Rights Reserved © Alcatel-Lucent 2009 13 Conclusion Enabling wide-area VM mobility in an efficient manner is of significant value to many cloud-based applications Proposed solution based on distributed forwarding and centralized control More efficient data forwarding and more flexible control unlike mobile IP solution Triangular routing is significantly reduced No modification to virtualization software or TCP/IP stack is needed No new requirement on correspondent node Connectivity is not affected during and after migration Several open issues remain for future research Use of this architecture for enabling new applications Simplifying implementation of current features