Transcript AKAMAI Content Delivery Services

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 ???
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History/Evolution
New Challenges of WWW
 Overheads
 E-Business Demands
 Solution
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New Challenges of WWW
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WWW has evolved beyond simply displaying static
webpages
New challenge of delivering pages quickly
Computing overhead associated with building
personalized pages, increasing delays, failures
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Overheads
Dynamic content creation places significant strain on
traditional web architecture
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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
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E-Business Demands
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Site experience and effectiveness
- Dynamic content
- Locally Personalization
- Download speeds
Site cost structure
- Investments
- Scalability
- Reliability
- Performance
- System management & Applications
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Quick Overview
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Quick Overview
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Solution
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Replicating content over a large number of distributed
servers without relying on centralized servers
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What’s all about CDS?
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CDS uses multiple web servers(CDN) distributed
across the world to deliver copies of your website
content
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CDN is made of following elements.
- Storage and Delivery nodes
- Central controller
- Central manager
- Request manager
- Central data store
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Advantages
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Speed
- Dispatching the requests to the closest site
- avoids congestion,delays and increases speed
often 2x to 10x speed improvement
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Reliability
- CDS site failure
- ISP’s server failure
typically 6x reliability improvement
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Flash Crowd Protection
- Multiple high capacity cache servers
handle large surges in traffic
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Akamai Technologies
About Akamai
 Embedded Object Replication.
 Edge Suite - Enhanced Performance.
 Advantages of EdgeSuite
 Enhanced DNS
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About Akamai
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Leading provider of secure, outsourced e-business
infrastructure services and software.
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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.
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Developed a set of breakthrough algorithms for
intelligently routing and replicating content over a large
network of distributed servers.
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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.
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Global Hosting Networks
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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.
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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.
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<IMG SRC= http://www.Provider.Com/image.Gif >
Changed to
<IMGSRC =
http://ghost1467.Ghosting.Akamai.Com/28765/www.Provider.Com/im
age.Gif >
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Architecture of GHN
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Content provider server.
- Provides the base HTML document.
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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.
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Hosting servers at the edge.
- serves the object to the client.
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<IMGSRC =
http://ghost1467.Ghosting.Akamai.Com/28765/www.Provider.Com/image.Gif >
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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.
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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.
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<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.
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Advantages
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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.
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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.
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How it works ?
How it Works
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esi
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Advantages of EdgeSuite
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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
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Enhanced DNS
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Distributed Network of DNS servers
DNS queries are always handled quickly and without
fail.
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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
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Things to look for in a CDS
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Content Acceptability
Performance Verification
Network Architecture
Transparency
Notification Service
Log Files
Cost and Bandwidth
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Leading Providers
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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
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Leading Providers(contd..)
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Digital Island
- medium to large companies
- accelerates HTML and images
- cost based on peak bandwidth
$18 per GB served with $1500/month minimum
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Leading Providers(contd..)
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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
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Public Vs Private
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Features to be considered
- Level of Distribution
- Targeted customers
- Resources
cutting-edge data center
experienced staff that can handle design and maintenance
- Investment
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References
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www.akamai.com
www.esi.org
www.digitalisland.net
www.solidspeed.com
http://www.webreference.com/new/cds.html
http://www.networkmagazine.com/article/NMG20
011203S0017
http://patft.uspto.gov
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Questions ???
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