CLOUD NETWORKING THE NEXT CHAPTER FLORIN BALUS
COMMON APPLICATION VIEW OF THE NETWORK Fallacies of Distributed Computing 1. The network is reliable. 2. Latency is zero. 3. Bandwidth is infinite. 4. The network is secure. 5. Topology doesn't change. 6. There is one administrator. 7. Transport cost is zero. 8. The network is homogeneous. Peter Deutsch - Sun Fellow, 1994 net wûrk : Unspeakably huge, complex, mysterious, stuffy network thing that nobody understands* 2 * = Gluecon Keynote Smarting the Dumb Pipes by Ross Turk. www.youtube.com/watch?v=tjtnmwzxm0c
CLOUD NETWORK PERFORMANCE H. Ballani, P. Costa, T. Karagiannis, A. Rawstron, Towards Predictable Datacenter Networks, Microsoft Research, ACM SIGCOMM 2011, MS Research MapReduce Task Enterprise DC 4 hours ($100) Popular Cloud 10-16 hours ($250-$400) Network performance can be a key obstacle to cloud adoption 3
DATA CENTER NETWORK VIRTUALIZATION L2 Service Virtualization The devil is in the details Promise of Nirvana 4
1 st GENERATION L2 SERVICE (VLANs) SERVER & STORAGE INFRASTRUCTURE ISSUES & LIMITATIONS Service Appliances 10.1.1.2 10.1.1.3 10.1.1.4 10.1.1.4 10.1.1.3 DC Core Network VLAN scalability L2 core scaling issues Management complexity Network stability Server & Storage Arrays 10.1.1.2 5
L2 NETWORK VIRTUALIZATION APPROACH (L2 over IP tunnels: VXLAN/NVGRE) Service Request SERVER & STORAGE INFRASTRUCTURE DC GWs ISSUES & LIMITATIONS IP Core Does not address enterprise use cases L2-Segment Bandwidth and routing inefficiencies VM VM TORs Core network complexity Storage Operational complexity VMs 6
ENTERPRISE APPLICATIONS CURRENT NETWORK VIEW REALITY L2-only virtualization L2-Segment VM VM Storage 7 Source: http://docs.oracle.com/cd/e12839_01/core.1111/e12037/overview.htm
1. REAL ENTERPRISE USE CASES Enterprise Site A Enterprise DC VM VM Subnet 1 Subnet 2 Firewall W W VPN Service L2 VPN Service VRF/Router VRF/Router Firewall BL BL Subnet 1 VLAN 11 VM VM VM VM Subnet 1 Subnet 2 VM VM VM VM DMZ designs Multi-tier Applications DC Service Hybrid Clouds DC Service L2/ Multi-DC - DR Services 8
2. BANDWIDTH AND LATENCY ISSUES -L4 services only in certain locations (VMs or ToRs) DC GWs 10 10 DC GWs Core Nodes Core Nodes TORs GW 12 11 11 TORs 12 11 GW V-Switches 10 11 12 12 11 11 11 12 10 12 B W B GW W VMs GW V-Switches 12 11 W B B 11 VMs 11 B 12 W 11 B Centralized gateways result in sub-optimal bandwidth utilization, performance issues, and choke-points 9
2. BANDWIDTH AND LATENCY ISSUES Using hardware-based routers Enterprise Site Enterprise Site WAN Service DC DC GW WAN Service VRF/Router TENANT 1 VLAN 12 VLAN 11 Aggregation Core L2 service VM VM VM VM Access Storage DC Gateways fail to solve the service problem 10
3. NETWORK COMPLEXITY Translation to L2 VLANs required Enterprise Site VPN Service Enterprise Site VPN Service DC GW TENANT 1 Subnet 1 Subnet 12 Spanning Tree VLANs VM VM VM VM Storage VM Router Backup Router External connectivity requires VLAN toolset and configuration 11
3. CORE NETWORK COMPLEXITY VXLAN Implementations require Multicast (PIM and IGMP) at the Core Per-Tenant multicast group VXLAN requires per-tenant state in the core network 12
4. INTERFACING TO EXISTING SERVICES OSS Nightmares Cloud Mgmt Interface? VLAN SP OSS MPLS-based WAN Service (Administrative Domain B) Data Center (Administrative Domain A) Significant costs and complexity in interfacing between different operational models and administrative domains 13
NETWORK SERVICE REQUIREMENTS Scalability No per-tenant state L2 Multi-tenancy Full tenant traffic isolation L2 & Services Support for real application topologies VPN Service Extension Hybrid and extended clouds SDN Programmability Rapid service deployment 14
DIDN T WE SOLVE THIS PROBLEM BEFORE? SERVICE EDGE (ETHERNET, IP / MPLS) IP CORE NETWORK CONTENT STORAGE & DISTRIBUTION INTERNET Issues and Limitations Not optimized for data center designs Unfamiliar protocols for IT organizations But, Rich toolkit of technologies and lessons learned CLOUD STORAGE AND COMPUTE 15
SOLUTION: DISTRIBUTED L2-L4 SERVICES Enterprise Site Enterprise Site WAN Service WAN Service DC PE Simple IP Core VRF/Router TENANT 1 VLAN 12 VLAN 11 VM VM VM VM Network Virtualization Edge (NVE) L2-L4 Services Distributed on all Edge Forwarding Elements of the DC 16
CONTROL AND DATA PLANE INTERACTIONS Cloud Management Service Management SP OSS APIs SDN/NVO3 Control Plane MP-BGP MP-BGP MP-BGP Compute & Enterprise Storage Data Plane IP Core Gateway MPLS VPN Services Site NVE/OVS NVO3 Tunnels 17
MULTI-DC AND MULTI-VENDOR SERVICES Enterprise Services Consumer Services IP/MPLS Core MP-BGP Control Plane BGP-MP BGP-MP Cloudstack DC Openstack Openstack DC Controlled BGP interoperability enables federation of multi-vendor cloud services 18
DRIVING TOWARD INTEROPERABILITY IETF NVO3 Working Group - Problem statement - draft-etf-nvo3-problem-statement - Framework - draft-ietf-nv03-framework - Data plane requirements - draft-bl-nvo0-dataplane-requirements - Control plane requirements Openflow Specification 1.3 - draft-drake-nvo3-evpn-control-plane - Federation of SDN Controller - draft-sb-nv03-sdn-federation 19
CLOUD NETWORK SERVICES RAPIDLY EVOLVING TO MEET ENTERPRISE NEEDS MPLS VPN Hybrid Clouds L2 Virtualization Services Service Chain (FW,LB) Performance SLAs 20
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