What Is CDN?
An outsourced delivery platform that websites and content owners use to offload the heavy lifting of serving bandwidth intensive objects
Bandwidth Intensive Objects
- Pictures
- Videos
- PDF’s
- MP3’s
- Software Downloads
- Live Event Streaming
Secret Sauce
Real time understanding of Internet conditions and congestion including:
- Distributed delivery locations reduce single points of failure
- Topographical targeting delivers content via most efficient path
- High capacity infrastructure to guarantee delivery
Types of CDN’s
- Global
- Regional
- P2P
- Hybrid
- Streaming Only
Why You Would Choose a CDN
Reduce Network Infrastructure Costs
- Bandwidth
- Equipment
- Colocation
- Technical Resources
Improve End User Performance
Increase Global Availability of Content
Scalability
Seasonal Traffic(www.cbssportsline.com)
March Madness Tournament
Unexpected Spikes
(death of famous celebrity)
Global Reach
(audience in Asia and US)
Factors When Choosing A CDN Provider
- Content & Users
- Capacity & Reach
- Format Support
- Burst Capabilities & Scalability
- Traffic Monitoring & Reporting
- Security & Authentication
- Provisioning & Installation
- Customer Service & NOC
- Performance & Rating
- Enhanced Features
- Professional Services
- Pricing & Commitments
Content and Users
What are you delivering???
1 Object to Millions of Visitors or Millions of Objects to Millions of Visitors
- Object Size
- Library Size
- Audience Size & Location
- Content Popularity & Longevity
Capacity & Reach
Does your CDN offer an expansive infrastructure that will get you as close to your end-user as possible while offering you true global reach at the same time?
Format Support
Not all CDN’s are created equal when it comes to their ability to support different delivery protocols.
Some are better at HTTP Caching while others excel at Flash or Windows Media
Some are better at handling small objects while others are better with large size objects
Burst Capabilities
What happens in the event of unforeseen traffic spikes?
Will your CDN be able to handle the traffic?
Does your CDN allow you to adjust your traffic real time?
Traffic Monitoring & Reporting
Does your CDN provider offer an easy to use portal to monitor your traffic for optimal performance and distribution?
- Real Time Traffic Volumes
- Overall Website Usage
- Abandon and Error Rates
- Historical Data Trends
- Raw Logs
Security & Authentication
Do you need to protect your content?
- Token-Based Authentication (URL & Client Checking)
- Geo Blocking
- Referrer Blocking
- IP Blocking
- DRM
Provisioning & Installation
Make sure provider understands the complexities of your applications to provision your service correctly, the 1st time.
Do their engineers provide a pre installation evaluation and design the appropriate configuration.
Customer Service & NOC
Response time is critical in this business. Do you receive the appropriate level of support for your needs?
Does the SLA support your application requirements?
How long can your content be offline?
Is 30 minutes ok or is 10 minutes too long?
Performance & Ratings


Enhanced Features
Do you need enhanced features to maximize your performance?
- Rate Limiting
- Flash Scrubbing
- Multiple Ingest Formats (ftp, sftp, rysnc, http)
Professional Services
Do they offer a professional services department that can help you support all aspects of your site?
- Encoding and Transcoding
- CMS: Content Management System
- Media Players
- E Commerce
- Mobile Applications
CDN Pricing
2 Ways to Buy CDN
Mbps
Best pricing option when:
- Predictable
- Consistent
- Follow the sun traffic
- No major spikes
GB Transferred
Best pricing option when:
- Un Predictable Traffic
- Major spikes<
- Pay for Use
- Eliminates Risk/li>
Commitment
What type of commitment are you signing to garner the pricing you need?
- Usage Based
- Flexible (Month-Month or Year)
- Demo period (is trial period long enough to test?)
- Exclusive
Questions to Ask
Http Caching
Caching Storage, Origin Traffic, Throttled Downloads, Jump to Byte, Windows Media / Flash
Push vs. Pull?
Self Provisioning of Publishing Points?
Storage
What ingest formats do they support? Is it multi-homed Storage?
Portal
Easy to understand, Give usage by URL, Functionality of Portal, Provisioning Via Portal?
Misc
How is authentication handled? How is file invalidation handled? What API’s do they have? How are logs retrieved? How long do they store logs? Can they re-run lost logs? Trial Trial Trial.
Predictions for CDN Providers
Consolidation through Mergers & BK’s
Larger CDN’s offering a differentiated solution, building applications that offer greater value
Smaller CDN’s are becoming more specialized, offering only HD/IPTV video delivery or web acceleration
Carriers & ISP’s entering the CDN market
