Lecture3_FR-ATM-PKSN-Cloud (1).pdf

Lecture III-IV Wide Area Networking (WAN) & Clouds’ Services Prepared For Cisco Dr. Reza Djavsnshir, Johns Hopkins University Wide Area Network Architectures  WAN Switching In a circuit switched network, a switched...

Lecture III-IV Wide Area Networking (WAN) & Clouds’ Services Prepared For Cisco Dr. Reza Djavsnshir, Johns Hopkins University Wide Area Network Architectures  WAN Switching In a circuit switched network, a switched dedicated circuit is created to connect the two or more parties, eliminating the need for source and destination address information.  Packet Switching In a packet switched network, packets of data travel one at a time from the message source to the message destination. The packet of data goes in one side of the PDN and comes out the other. The physical path which any packet takes may be different than other packets and in any case, is unknown to the end users. Packet switches pass packets among themselves as the packets are routed from source to destination. WAN Switching  Connectionless vs. Connection-oriented Packet Switched services Connectionless Service: In order for a switch to process any packet of data, packet address information be included on each packet. Each switch reads and processes the packet by making routing decisions based upon the destination address and network conditions. The full destination address uniquely identifying the ultimate destination of each packet is known as the global address.  Connectionless vs. Connection-oriented Packet Switched services IT Engineers, make the distinctions between Connectionless and Connection Oriented Protocols by making changes ands modifications at: Transport Layer Network (Packet) Layer Data Link (Frame) Layer. Note: In LANs IEEE 802.2 LLC supports both Connectionless and Connection-oriented Protocols.  WAN Switching Connection-oriented v.s. Connectionless Packet Switched Networks Datagrams, UDP*, IP (Network Layer Protocols) Podcasting are Connectionless Service Each Packet (containing part of a message) may arrive out of order at the destination due to the speed and condition of the alternate paths within the Packet Switched Network. The data message must be pieced back together in proper order by the destination PAD before final transmission to the destination terminal computer’s address. These self-sufficient packets containing full address information plus a message segment are known as Datagrams. *Universal Data Protocol (UDP): IP is UDP and BY ITESELF ALONE is CONNECTIONLESS Protocol. However, With TCP it becomes CONNECTION ORIENTED. Connection Oriented Services (TCP –Transport Layer Protocol) WAN Switching Data-link (Frame) layer OSI v.s. WAN ISO/OSI vs TCP/IP X.25 implementation Frame Relay Error Correction  A Frame’s Make up Note: Octet is an engineering term for a Character or a Byte = 8 bits  Frame Relay CIR: Committed Info Rate  Committed Information Rate (CIR) Is a good feature of Frame Relay Services That is, you can buy both Committed Information Transmission and Also Variable Rates if you need it.  How BECN & FECN Work? When Frame Relay Switch B is Getting Congested, it issues BECN & FECN to its Adjacent Switches (A & C). BECN FECN A B C Frame Relay Voice over Frame Relay  ATM As ATM switches utilize very short, fixed-length cells (53 Bytes/Octets or Characters), they process information much faster than frame relay switches. 48 Bytes/Octets/Characters of user’s information And 5 Bytes/Octets or Character s of Overhead The fixed-length cells are enhanced with connection- oriented services. Note: Recall: 1 Byte = 1 Character =1 Octet = 8 bits  ATM The lack of a predictable, Slowness for Live Video and Transmission were key limitations of Frame Relay, which prevented the widespread use of this technology for converged applications (Voice, Data, and Videos). The predictability and consistency of transmission of ATM are the features that make this technology a good choice for transporting real-time services Although access to the ATM core is typically provided by T-carrier services (T-1 or T-3), you better use Fiber Optic connections (OCs)  ATM Note Cost Figures: $ CBR > $ VBR > $ ABR ATM Implementation  ATM Adaptive Layers (AALs): ATM Protocols that Converts users Traffic payload into ATM Cells (53-Byte, that includes 5 Bytes of Overhead) AAL-1: Connection Oriented, Fixed Delay, Used in TDM (Used for Voice) AAL-2: Connection Oriented, Fixed Delay, Used for Compressed Video AAL-3/4: Connectionless, Variable Delay , Used for Multimedia (Not Popular) & *** AAL-5: Connection Oriented, Minimum Fixed Delay, Used for Multimedia – Voice, Data, Lived and Compressed Videos (Most POPULAR, ATM Layer, Replaced ALL3/4 and Can Also do ALL-1, and ALL-2)  Peer-to-Peer (Source -Destination) Communication in ATM Protocol’s Layers Voice over ATM CLOUD COMPUTING SERVICE  Cloud Computing The term Cloud is relatively new, but the Concept has been evolving since the late 1980s. – Programmers around the globe has been working (developing and supporting) remote Software.  History The 1950s Mainframe Computers via Thin Clients – Allowed multiple users to share access to the computer from multiple terminals The 1960s–1990s John McCarthy - Public Utility - Comparison to the electricity industry and the use of public, private, government, and community forms The 1990s In the 1990s, telecommunications companies, who previously offered primarily dedicated point-to-point data circuits, began offering virtual private network (VPN) Use of the infrastructure, platform and applications with prioritized access to the CPU and efficiency for the end users. Since 2000 Amazon - key role modernizing their data centers, which, like most computer networks, Using as little as 10% of their capacity at any one time Amazon initiated a new product development effort to provide cloud computing to external customers, and launched Amazon Web Services (AWS) on a utility computing basis in 2006 Modern Days The present availability of high-capacity networks, low-cost computers and storage devices as well as the widespread adoption of hardware virtualization, service-oriented architecture, autonomic, and utility computing have led to a growth in cloud computing. 32  What is Cloud Computing any why?  Cloud Computing is a general term used to describe a new class of network based computing that takes place over the Internet ◦ Using Internet for communication, hardware, software and networking services to clients 33  Cloud Computing Factors enabling the remote (Cloud) computing: 1. Low Cost & High-speed Internet Access 2. Low Cost Memory Storage 3. Multi-processing Computers & Servers that are able to support Various Operating Systems & Applications. 4. Vast amounts of Spare Computing Capacities at Tech Companies such as Amazon, Google, Microsoft, and Apple…  Cloud Computing simply is:  Cloud computing is an umbrella term used to refer to Internet based, Applications, Development and Services  A number of characteristics define cloud applications services and infrastructure: ◦ Remotely Hosted: Services or Information is hosted on remote infrastructure ◦ Ubiquitous Availability: Services or Information are Available from anywhere ◦ Commoditized: The result is a utility computing model similar to traditional utilities, like gas and electricity - you pay for what you would want  API in Cloud Computing Customers – Different Cloud Applications and Services are Linked by: – Application Program Interfaces (APIs) API enables Remote Computers to Access and Link to other Different Computers (Servers) and Exchange Info with them over the Cloud. API Translates and Interprets Commands and Content Information between dissimilar computer Programs.  Cloud Computing Benefits to Consumers, Non-Profits, Developing Countries, and Small Businesses: – Cloud applications Costs less than purchasing the same Application. – Cloud Applications are Accessible via any Mobile Devices – No need to buy expensive and heavy devices (hardware) loaded with all Apps – Don’t need to spend money to Support, Maintenance, & Upgrades. Small Businesses use the Cloud to share Office Applications Resources,… instead of using LAN (Cuts the cost to buy and maintain LAN). Backup, Virus Protections, and other services are available (Carbonite, EMC’s Mozy.com),…  Some Concerns Moving Applications from Firms’ Data Centers to the Cloud may seem to be difficult: – Rewriting that Application, API, Changing IP or Addresses,…However, Companies such as Cloud Switch Inc.,… offer APIs and other Software that enables customers portability to the Cloud and within Clouds Security (Sharing the same Servers or Clouds) – For Extra charges Cloud Providers, offer VPN and Private Cloud Services – Servers,…  What is Cloud Computing any why?  Shared pool of configurable computing resources  On-demand network access 39  Provisioned by the Service Provider Cloud Architecture Platform or 40  Three-layer Architecture 1. IaaS: Infrastructure as a Service 2. PaaS: Platform as a Service 3. SaaS: Software as a Service 3. SaaS 2. PaaS 1. IaaS  Cloud Computing Layers CRM: Customer Relation Management  Cloud’s Essential Characteristics  “No-Need-to-Know” in terms of the underlying details of infrastructure, applications interface with the infrastructure via the APIs  “Flexibility and Elasticity” allows these systems to scale up and down at will as needed ◦ utilizing the resources of all kinds:  CPU, Storage, Server Capacity, Load Balancing, and Data-Bases,..  PAYGO- “Pay as Much as Used and Needed” type of utility computing and the “Always on, Anywhere and Any Place” type of network-based computing. 43  What is Elastic Computing or Cloud Elasticity Elastic computing is the ability to quickly expand or decrease computer processing, memory, and storage resources to meet changing demands without worrying about capacity planning and engineering for peak usage. Typically controlled by system monitoring tools, elastic computing matches the amount of resources allocated to the amount of resources actually needed without disrupting operations. With cloud elasticity, a company avoids paying for unused capacity or idle resources and doesn’t have to worry about investing in the purchase or maintenance of additional resources and equipment.  Benefits of Elastic Computing (Cloud Elasticity) Elastic computing is more efficient than your typical IT infrastructure, is typically automated so it doesn’t have to rely on human administrators around the clock and offers continuous availability of services by avoiding unnecessary slowdowns or service interruptions.  Software as a Service (SaaS) SaaS is a model of Software Services where an Application is hosted as a service provided to customers across the Internet. Users pay monthly fees to use the Application Software programs. SaaS removes the burden of software Purchases, Maintenance/support, and Upgrades, but users loses Control. 46  Platform as a Service (PaaS) ◦ Collection/group of Integrated Hardware, Software, Dbase Engine, Web Services, Software Development Tools,... (called a Platform) offered from remote locations be a vendor Platforms Enables the users to Access the Applications by providing very Simple Graphical Interface called API (Applications Programming Interface)  Platform as a Service (PaaS): Google’s Business Model A Cloud Provider makes its Hardware and Basic Applications suits available to its users The User Controls the Application Software deployment and configuration settings, but not the underlying infrastructure. 48  Platform as a Service (PaaS) Provides on Demand Services, that are always on, anywhere, anytime and any place PAYGO for use as Needed – Scale up / Down in capacity and functionalities Hardware and software services available to Public, Corporations and Businesses 49  Infrastructure as a Service (IaaS) Cloud Providers Provide Virtual Systems (Infrastructures- Hardware Platforms, Servers, Storage, Network connectivity and runs them. IaaS Clouds Providers offer Virtual Local Area Networks (VLANs), Resources Disk Image Library, Storage, Firewalls, IP addresses,& software bundles. Software Developers (users) create their own Applications on the Virtual Systems (Infrastructures -Hardware Platforms, Servers and Storage Infrastructures,..) that are Owned by the Cloud Provider. 50  Cloud Storage  Cloud providers sell Data Storage Capacity to other companies or users.  They also allows data stored remotely to be Temporarily Cached on Desktop computers, mobile phones or other Internet-linked devices.  Amazon’s Elastic Computing Cloud (EC2) & Simple Storage Solution (S3) are well known examples 51 Amazon’s Storage Service Unlimited Storage. Pay for what you use: – $0.20 per GByte of data transferred – $0.15 per GByte-Month for storage used, – Second Life Update: 1TBytes, 40,000 downloads in 24 hours - $200 52  Utility Computing – EC2  Amazon Elastic Computing Cloud (EC2): ◦ Elastic, 1 to 100+ PCs, ◦ Fairly cheap ◦ Supports “Live Migration” of a virtual machine between hosts. 53 Some Commercial Cloud Offerings 54  Cloud-Sourcing  Why is it becoming a Big Deal: ◦ Using high-scale/low-cost providers ◦ Any time/Any where access via web browser ◦ Elastic - Rapid scalability; incremental cost and load sharing  CONCERNS: oNo standard API – oControl of data, and service parameters, oPrivacy, Security, Trust… oPerformance, Reliability, and SLAs, oInteraction between Cloud providers, 55  Business and Entrepreneurship Opportunities for You Opportunities: –It enables you to provide your chosen Services without any huge investment on their Infrastructure (start from your basement/garage) –Data and services are stored remotely but accessible from “anywhere” 56  Advantages of Cloud Computing Lower computer costs Improved performance Reduced software costs Instant software updates Improved document format compatibility Unlimited storage capacity Increased data reliability Universal document access Latest version availability Easier group collaboration Device independence 57  Challenges –Dependence on others: Dependence on Others are likely become the bigger Internet companies like Google and IBM, who may monopolise the market. Some argue the Return of Supercomputers to the time of Mainframes that the PC was a reaction against.  Challenges Challenges (Continued): –Security & Privacy could prove to be a big issue: It is still unclear how safe out-sourced data is and when using these services ownership of data is not always clear. But, VPN, and Private Cloud Services (Servers,…), working on it - in progress –API Conversion, when Chaning from one Cloud Provider to another. –There are also issues relating to policy and access: If your information is stored abroad whose policy do you adhere to ours? There have been cases of users being locked out of accounts and losing access to info.  Opportunities: –Cloud computing works using economies of scale: It potentially lowers the outlay expense for start up companies, as they would no longer need to buy their own software or servers Cost would be by on-demand pricing  The Future Cloud based Smart Cities, Smart Infrastructure, the Internet of Things (IoT) is the future in all Business Domains and Entrepreneurial activities for the next 50+ years. Smart Cities are based on Cloud and Mobile Telecom Services. If you learn it your success is guaranteed for the rest of your life. Many new Open Source Systems appearing that can install and run on Clouds Next Generation Homes with Computer Screen Walls. 61 APPENDIX  Cloud Service Models SalesForce CRM Google App Engine 63 Adopted from: Effectively and Securely Using the Cloud Computing Paradigm by peter Mell, Tim Grance  Different Cloud Computing Layers MS Live/ExchangeLabs, IBM, Application Service Google Apps; Salesforce.com (SaaS) Quicken Online, Zoho, Cisco Google App Engine, Mosso, Application Platform Force.com, Engine Yard, Facebook, Heroku, AWS Server Platform 3Tera, EC2, SliceHost, GoGrid, RightScale, Linode Storage Platform Amazon S3, Dell, Apple,... 64  Virtualization Virtualization: Provides an Execution Environment that can be made dynamically available to authorized clients by providing – Resources – such as CPU, Memory share, –Software Configuration (e.g. O/S, provided services). App App App OS OS OS Hypervisor Hardware Virtual Machine  Virtualization: Virtual Systems (VS) Implementing Virtual Machines (VS): – VS Emulates a physical Host Machine, –Hypervisor Emulates Instructions from VMs, –VM Ware, Xen, etc. Provide Infrastructure API: –Plug-ins to hardware/support structures App App App OS OS OS Hypervisor Hardware Virtual Machine V  Advantages of Virtual Systems ◦ Run Operating Systems where the physical hardware is unavailable ◦ Emulate more machines than are physically available ◦ Timeshare loaded systems on one host ◦ Debug problems (suspend and resume the problem machine) ◦ Easy migration of virtual machines (shutdown needed or not) ◦ Run legacy systems 67 Purpose and Benefits for Virtualization  Cloud computing enables companies and applications, which are system infrastructure dependent, to be infrastructure-less  By using the Cloud infrastructure on “pay as used and on demand”, all of us can save in capital and operational investment  Clients can: ◦ Store their data on the platform instead of on their own desktop PCs or on their own servers ◦ Store their applications on the cloud and use the servers within the cloud to do processing and data manipulations etc 68 Cloud Taxonomy 69