Virtualization: Transforming Hardware into Software

1. UNIT VI: Advance Network TechnologiesVirtualization, Software defined network, ATM (Overview, Protocol Architecture, AAL), GMPLS, Introduction of optical networks, Propagation of Signals in Optical Fiber, Client Layers of the Optical Layer 8 Hrs

2. Virtualization: What Is Virtualization? How does it works? Background and evolution, Advantages and disadvantages, Platform Virtualization, Resources Virtualization, Hypervisor, Massively virtualized model-cloud. Ref: Operating Systems—A Concept-Based Approach,  D. M. Dhamdhere, McGraw-Hill, 2008

3. What is virtualization? • Virtualization allows one computer to do the job of multiple computers. • Virtual environments let one computer host multiple operating systems at the same time

5. How does it work? • Virtualization transforms hardware into software. • It is the creation of a fully functional virtual computer that can run its own applications and operating system. • Creates virtual elements of the CPU, RAM, and hard disk.

6. Background and Evolution • Virtualization arose from a need in the 1960’s to partition large mainframe hardware. • Improved in the 1990s to allow mainframes to multitask. • First implemented by IBM more than 30 years ago.

8. Virtualization • It is divided into two main categories: • Platform virtualization involves the simulation of virtual machines. • Resource virtualization involves the simulation of combined, fragmented, or simplified resources.

9. Platform Virtualization • the creation of a virtual machine using a combination of hardware and software is referred to as platform virtualization • Platform virtualization is performed on a given hardware platform by "host" software (a control program), which creates a simulated computer environment (a virtual machine) for its "guest" software. • The "guest" software, which is often itself a complete operating system, runs just as if it were installed on a stand-alone hardware platform. • Typically, many such virtual machines are simulated on a given physical machine. • For the "guest" system to function, the simulation must be robust enough to support all the guest system's external interfaces, which (depending on the type of virtualization) may include hardware drivers.

10. Resource Virtualization • The basic concept of platform virtualization, was later extended to the virtualization of specific system resources, such as storage volumes, name spaces, and network resources.

11. Resource Virtualization • Resource aggregation, spanning, or concatenation combines individual components into larger resources or resource pools. For example: • RAID and volume managers combine many disks into one large logical disk. • Storage Virtualization refers to the process of completely abstracting logical storage from physical storage, and is commonly used in SANs. The physical storage resources are aggregated into storage pools, from which the logical storage is created. Multiple independent storage devices, which may be scattered over a network, appear to the user as a single, location-independent, monolithic storage device, which can be managed centrally. • Channel bonding and network equipment use multiple links combined to work as though they offered a single, higher-bandwidth link. • Virtual Private Network (VPN), Network Address Translation (NAT), and similar networking technologies create a virtualized network namespace within or across network subnets. • Multiprocessor and multi-core computer systems often present what appears as a single, fast processor.

12. Hypervisor • In computing, a hypervisor (also: virtual machine monitor) is a virtualization platform that allows multiple operating systems to run on a host computer at the same time. The term usually refers to an implementation using full virtualization.

13. Hypervisor Types • Hypervisors are currently classified in two types: • Type 1 hypervisor : A software that runs directly on a given hardware platform (as an operating system control program Examples : VMware's ESX Server, and Sun's Hypervisor • Type 2 hypervisor :A software that runs within an operating system environment. Examples include VMware server and Microsoft Virtual Server.

14. Virtualization - Why Virtualize? • Reduce Real Estate Needs • Increase Up Time • Reduce CO2 Emissions, Power and Cooling Requirements • Increase Flexibility • Reduce Overall Costs

15. Massively Virtualized Model - Cloud

16. Cloud Computing - Services Software as a Service - SaaS Platform as a Service - PaaS Infrastructure as a Service - IaaS

17. Advantages: • Benefits include freedom in choice of operating system. • It saves time and money. • Consolidates server and infrastructure. • Makes it easier to manage and secure desktop environments. Disadvantages • Only powerful computers can successfully create virtual environment. • Requires training to operate.

18. Advance Network Technologies • Software defined network: Traditional Computer Networks, Limitations of Current Networks, What is SDN? Background, OS for networks, What is OpenFlow? How it helps SDN, The current status & the future of SDN (Case studies) • Ref: http://www.cs.princeton.edu/courses/archive/spr12/cos461/

19. Traditional Computer Networks Data plane: Packet streaming • Forward, filter, buffer, mark, • rate-limit, and measure packets

20. Traditional Computer Networks Control plane: Distributed algorithms • Track topology changes, compute routes, install forwarding rules

21. Traditional Computer Networks Management plane: Human time scale • Collect measurements and configure the equipment

22. Limitations of Current Networks Switches

23. Limitations of Current Networks • Enterprise networks are difficult to manage • “New control requirements have arisen”: • Greater scale • Migration of VMS • How to easily configure huge networks?

24. Limitations of Current Networks • Old ways to configure a network App App App Operating System Specialized Packet Forwarding Hardware App App App Operating System Specialized Packet Forwarding Hardware App App App Operating System App App App Specialized Packet Forwarding Hardware Operating System Specialized Packet Forwarding Hardware App App App Operating System Specialized Packet Forwarding Hardware

25. Feature Million of linesof source code Billions of gates Limitations of Current Networks Many complex functions baked into infrastructure • OSPF, BGP, multicast, differentiated services,Traffic Engineering, NAT, firewalls, … Feature Operating System Specialized Packet Forwarding Hardware Cannot dynamically change according to network conditions

26. Idea: An OS for Networks Closed App App App Operating System App App App Specialized Packet Forwarding Hardware Operating System App App App Specialized Packet Forwarding Hardware App App App Operating System Specialized Packet Forwarding Hardware Operating System App App App Specialized Packet Forwarding Hardware Operating System Specialized Packet Forwarding Hardware

27. Idea: An OS for Networks Control Programs Network Operating System App App App Operating System App App App Specialized Packet Forwarding Hardware Operating System App App App Specialized Packet Forwarding Hardware App App App Operating System Specialized Packet Forwarding Hardware Operating System App App App Specialized Packet Forwarding Hardware Operating System Specialized Packet Forwarding Hardware

28. Idea: An OS for Networks Control Programs Network Operating System Simple Packet Forwarding Hardware Simple Packet Forwarding Hardware Simple Packet Forwarding Hardware Simple Packet Forwarding Hardware Simple Packet Forwarding Hardware OpenFlow/SDN tutorial, Srini Seetharaman, Deutsche Telekom, Silicon Valley Innovation Center

29. Idea: An OS for Networks Protocols Protocols Software-Defined Networking (SDN) Control Programs Global Network View Network Operating System Control via forwarding interface

30. Software Defined Networking • No longer designing distributed control protocols • Much easier to write, verify, maintain, … • An interface for programming • NOS serves as fundamental control block • With a global view of network

31. Software Defined Networking • Examples • Ethane: network-wide access-control • Power Management

32. OpenFlow • “OpenFlow: Enabling Innovation in Campus Networks” • Like hardware drivers – interface between switches and Network OS

33. OpenFlow Control Path (Software) Data Path (Hardware) OpenFlow/SDN tutorial, Srini Seetharaman, Deutsche Telekom, Silicon Valley Innovation Center

34. OpenFlow OpenFlow Controller OpenFlow Protocol (SSL/TCP) Control Path OpenFlow Data Path (Hardware)

35. MAC src MAC dst IP Src IP Dst TCP sport TCP dport * * * 5.6.7.8 * * port 1 Action Controller OpenFlow Switching PC OpenFlow Client Software Layer OpenFlow Table Hardware Layer port 2 port 1 port 3 port 4 5.6.7.8 1.2.3.4 35

36. OpenFlow Table Entry Rule Action Stats Packet + byte counters • Forward packet to port(s) • Encapsulate and forward to controller • Drop packet • Send to normal processing pipeline • … Switch Port MAC src MAC dst Eth type VLAN ID IP Src IP Dst IP Prot TCP sport TCP dport + mask

37. Switch Port Switch Port Switch Port MAC src MAC src MAC src MAC dst MAC dst MAC dst Eth type Eth type Eth type VLAN ID VLAN ID VLAN ID IP Src IP Src IP Src IP Dst IP Dst IP Dst IP Prot IP Prot IP Prot TCP sport TCP sport TCP sport TCP dport TCP dport TCP dport Action Action Action OpenFlow Examples Switching 00:1f:.. * * * * * * * * * port6 Routing * * * * * * 5.6.7.8 * * * port6 Firewall * * * * * * * * * 22 drop

38. OpenFlow • Standard way to control flow-tables in commercial switches and routers • Just need to update firmware • Essential to the implementation of SDN

39. ATM: Overview, Protocol Architecture, AAL, GMPLS: Why GMPLS?GMPLS and MPLS, Control interfaces, Challenges of GMPLS, Proposed techniques: Suggested label, Bi-direction LSP setup, LMP, etc Ref: 1.ATM:William Stallings, Data and Computer Communications7thEdition 2. GMPLS: bnrg.cs.berkeley.edu/~randy/Courses/CS294.S02

40. WHAT’S ATM? • ATM is Asynchronous Transfer Mode. • ATM is a connection-oriented, high-speed, low-delay switching and transmission technology that uses short and fixed-size packets, called cells, to transport information. • ATM is originally the transfer mode for implementing Broadband ISDN (B-ISDN)but it is also implemented in non-ISDN environments where very high data rates are required

41. BROADBAND AND B-ISDN Broadband: "A service or system requiring transmission channel capable of supporting rates greater than the primary rate.“ Broadband-Integrated Service Digital Network (B-ISDN): A standard for transmitting voice, video and data at the same time over fiber optic telephone lines The goal of B-ISDN is to accommodate all existing services along withthose that will come in the future. The services that BISDN will supportinclude • narrowband services, such as voice, voice band data,facsimile, telemetry, videotex, electronic mail, • wideband servicessuch as T1, and • broadband services such as video conference,high speed data, video on demand. BISDN is also to support point-to-point,point-to-multipoint and multipoint-to-multipoint connectivities.

42. ATM OVERVIEW • Used in both WAN and LAN settings • Signaling (connection setup) Protocol: • Packets are called cells (53 bytes) • 5-byte header + 48-byte payload • Commonly transmitted over SONET • other physical layers possible • Connections can be switched (SVC), or permanent (PVC). • ATM operates on a best effort basis. • ATM guarantees that cells will not be disordered. • Two types of connections: • Point-to-point • Multipoint (Multicast) • Four Types of Services: • CBR (Constant Bit Rate) • VBR (Variable Bit Rate) • ABR (Available Bit Rate) Flow Control, Rate-based, Credit- based • UBR (Unspecific Bit Rate) No Flow control.

43. ATM Characteristics • No error protection or flow control on a link-by-link basis. • ATM operates in a connection-oriented mode. • The header functionality is reduced. • The information field length is relatively small and fixed. • All data types are the same

44. Why ATM? • International standard-based technology (for interoperability) • Low network latency (for voice, video, and real-time applications) • Low variance of delay (for voice and video transmission) • Guaranteed quality of service • High capacity switching (multi-giga bits per second) • Bandwidth flexibility (dynamically assigned to users)

45. Why ATM? (con’t) • Scalability (capacity may be increased on demand) • Medium not shared for ATM LAN (no degradation in performance as traffic load or number of users increases) • Supports a wide range of user access speeds • Appropriate (seamless integration) for LANs, MANs, and WANs • Supports audio, video, imagery, and data traffic (for integrated services)

46. ATM NETWORKS • Public ATM Network: • Provided by public telecommunications carriers (e.g., AT&T, MCI WorldCom, and Sprint) • Interconnects private ATM networks • Interconnects remote non-ATM LANs • Interconnects individual users • Private ATM Network: • Owned by private organizations • Interconnects low speed/shared medium LANs (e.g., Ethernet, Token Ring, FDDI) as a backbone network • Interconnects individual users as the front-end LAN for high performance or multimedia applications

47. Switches in the middle End systems of ATM

48. Private ATM Network Public ATM Network Token Ring FDDI Token Ring File Server FDDI Voice Ethernet Edge Switch Video PBX Mainframe Computer FDDI Ethernet Private ATM Switch Edge Switch Edge Switch Edge Switch Mainframe Computer PBX Video Ethernet Voice Video

49. P-NNI Private ATM WAN Public ATM Network Private ATM LAN Public ATM Network ATM Interfaces Private UNI Public UNI B-ICI

50. How ATM Works? • ATM is connection-oriented -- an end-to-end connection must be established and routing tables setup prior to cell transmission • Once a connection is established, the ATM network will provide end-to-end Quality of Service (QoS) to the end users • All traffic, whether voice, video, image, or data is divided into 53-byte cells and routed in sequence across the ATM network • Routing information is carried in the header of each cell • Routing decisions and switching are performed by hardware in ATM switches • Cells are reassembled into voice, video, image, or data at the destination