370 likes | 447 Vues
AKAMAI Content Delivery Services. CIS726 : PRESENTATION Avinash Ponugoti Nagarjuna Nagulapati Sathish Kumar Yenna. Outline. History/Evolution What’s all about CDS? Akamai Technologies Things to look for in a CDS Public Vs Private References Questions ???. History/Evolution.
E N D
AKAMAIContent Delivery Services CIS726 : PRESENTATION Avinash Ponugoti Nagarjuna Nagulapati Sathish Kumar Yenna
Outline • History/Evolution • What’s all about CDS? • Akamai Technologies • Things to look for in a CDS • Public Vs Private • References • Questions ??? Content Delivery Services
History/Evolution • New Challenges of WWW • Overheads • E-Business Demands • Solution Content Delivery Services
New Challenges of WWW • WWW has evolved beyond simply displaying static webpages • New challenge of delivering pages quickly • Computing overhead associated with building personalized pages, increasing delays, failures Content Delivery Services
Overheads Dynamic content creation places significant strain on traditional web architecture • Network overhead -User requests are dispatched to appropriate modules to serve • Processing overhead -Modules determine which data to fetch and present • Disk I/O -Modules query the backend databases Content Delivery Services
E-Business Demands • Site experience and effectiveness - Dynamic content - Locally Personalization - Download speeds • Site cost structure - Investments - Scalability - Reliability - Performance - System management & Applications Content Delivery Services
Quick Overview Content Delivery Services
Quick Overview Content Delivery Services
Solution • Replicating content over a large number of distributed servers without relying on centralized servers Content Delivery Services
What’s all about CDS? • CDS uses multiple web servers(CDN) distributed across the world to deliver copies of your website content • CDN is made of following elements. - Storage and Delivery nodes - Central controller - Central manager - Request manager - Central data store Content Delivery Services
Advantages • Speed - Dispatching the requests to the closest site - avoids congestion,delays and increases speed often 2x to 10x speed improvement • Reliability - CDS site failure - ISP’s server failure typically 6x reliability improvement • Flash Crowd Protection - Multiple high capacity cache servers handle large surges in traffic Content Delivery Services
Akamai Technologies • About Akamai • Embedded Object Replication. • Edge Suite - Enhanced Performance. • Advantages of EdgeSuite • Enhanced DNS Content Delivery Services
About Akamai • Leading provider of secure, outsourced e-business infrastructure services and software. • Akamai's intelligent edge platform for content, streaming media, and application delivery comprises more than 13,500 servers within over 1,000 networks in 66 countries. • Developed a set of breakthrough algorithms for intelligently routing and replicating content over a large network of distributed servers. Content Delivery Services
Embedded Object Replication • Global Hosting Networks. MIT • Network Smart Monitoring System - System and method for optimized storage and retrieval of data on a distributed Network. Content Delivery Services
Global Hosting Networks • A method for intelligently routing and replicating content over a large network of distributed servers. Without disrupting the content provider’s direct relationship with end user. • Base HTML document portion of a web page is served from the content provider’s site. While one or more embedded objects serviced from hosting server nearest to the end user. Content Delivery Services
Overview of GHN • Browser sends a request to provider web site. It receives the request in the same way as if GHN was not being implemented. • Textual part of the page is returned as would be under normal circumstances. • <IMG SRC= http://www.Provider.Com/image.Gif > Changed to <IMGSRC = http://ghost1467.Ghosting.Akamai.Com/28765/www.Provider.Com/image.Gif > Content Delivery Services
Architecture of GHN • Content provider server. - Provides the base HTML document. • Hierarchy of DNS servers. - The top level DNS servers identify a low level DNS servers and redirects the request to them. The lowest level DNS server resolves the request to an IP address for an Hosting server. • Hosting servers at the edge. - serves the object to the client. Content Delivery Services
<IMGSRC = http://ghost1467.Ghosting.Akamai.Com/28765/www.Provider.Com/image.Gif > Content Delivery Services
Content Distribution and Replication • Copies distributed so that no server becomes overloaded. • Copies tend to be on same server with time. • That is, hosting servers do not have copies of all the objects in the provider server. • Buddy servers – Used to assume the hosting responsibilities of associated hosting server in the event of a failure condition. Content Delivery Services
Load Balancing • Embedded object requests are distributed . • Embedded object URL is modified by prepending a virtual server host name. • Modified URL includes a value generated by a hash function, used to distribute embedded objects. • URL includes a ‘finger print’ value for the embedded object. Value used to check if object is modified. Content Delivery Services
<IMGSRC = http://ghost1467.Ghosting.Akamai.Com/28765/www.Provider.Com/image.Gif > Virtual Server Host Name Hash Value of Image.gif This process is preferably performed offline, Whenever an object is updated. Content Delivery Services
Advantages • No disruption of Content Providers relationship with the user. - Accurate count of hits. - tailoring content – advertising. • Fault tolerant – Buddy servers. • Load balancing- Automatic content managment. • End user never receives outdated or stale content. • Scalability, Flash crowd protection, bandwidth saving. • Control of Proprietary Databases and Confidential Information. Content Delivery Services
EdgeSuite - Enhanced Performance To fully realize - performance, - reliability, - scalability - return on investment the content delivery must be applied across an entire site’s content not just the embedded objects. EdgeSuite is the only service capable of providing content delivery’s benefits to all of a site’s content. Content Delivery Services
How it Works Content Delivery Services
esi Content Delivery Services
Advantages of EdgeSuite • Faster and more reliability attract and retain customers • Secure Content uses Secure Sockets Layer • Digitized Downloads • Streaming Delivery deliver media streams for on-demand viewing • Tiered Distribution delivery of site’s content with tiered architecture • Site Fail over Site mirroring Disaster Recovery Site Maintenance • Provide Popularity Reports enable to tailor marketing spending dollars Content Delivery Services
Enhanced DNS • Distributed Network of DNS servers DNS queries are always handled quickly and without fail. • Multiple Physical machines Enhanced DNS global service backs each logical name server IP address with multiple physical machines that are located in several networks Users are transparently directed to the topologically closest name server Content Delivery Services
Things to look for in a CDS • Content Acceptability • Performance Verification • Network Architecture • Transparency • Notification Service • Log Files • Cost and Bandwidth Content Delivery Services
Leading Providers • SolidSpeed Networks - small to medium sized businesses - accelerates HTML and images - doesn’t require changes to website content - provides software to measure speed and availability of websites - provides complete log files - reasonable price based on number of hits minimum $50/month and scales upward Content Delivery Services
Leading Providers(contd..) • Digital Island - medium to large companies - accelerates HTML and images - cost based on peak bandwidth $18 per GB served with $1500/month minimum Content Delivery Services
Leading Providers(contd..) • Akamai - large company sites - modifications to site content required - Akamai provides tools to assist this process - cost based on peak bandwidth - starts at $2000 per megabit/sec served per month - requires 12 month minimum contract Content Delivery Services
Public Vs Private • Features to be considered - Level of Distribution - Targeted customers - Resources cutting-edgedata center experienced staff that can handle design and maintenance - Investment Content Delivery Services
References • www.akamai.com • www.esi.org • www.digitalisland.net • www.solidspeed.com • http://www.webreference.com/new/cds.html • http://www.networkmagazine.com/article/NMG20011203S0017 • http://patft.uspto.gov Content Delivery Services
Questions ??? Content Delivery Services