ISPCON CDN FaceOff:
Content Bridge, Content Alliance, and Akamai

A pair of multi-vendor cooperatives, Content Bridge and Content Alliance, have been launched to enable more effective competition with CDN market-leader Akamai. How will they do it? ISPCON keynoters offer insight.

Lisa Phifer VP Core Competence, Inc. [January 4, 2001]

Content Delivery Networks (CDNs) were a hot topic at November's ISPCON. At iBAND keynotes, executives presenting on behalf of Cisco's Content Alliance and Adero's Content Bridge disagreed on methods. But they shared a common vision: allow providers to distribute CDN wealth through content peering. The unspoken threat spurring both initiatives: market leader Akamai.

The CDN promise
Ed Haslam, Chief Strategist at Inktomi, defined a CDN as a total network service implementation that ties content creators and consumers together. By coupling caching and load balancing technologies to push content from creators to the network edge, today's CDNs operate as independent overlay networks.

Content creators and consumers benefit from high-quality delivery, particularly for rich media (images, streaming). CDN operators like Akamai, Digital Island, Mirror Image, and Clearway derive revenue from content creators: those who pay for premium delivery. Ultimately, that revenue must be shared across the CDN food chain: With webhosters that inject content into the CDN, with providers that distribute content across high-speed backbones, and with ISPs that deliver content from edge caches to consumers.

Haslam believes that the technology components of CDNs are well understood, but that business models are just now evolving. Increasingly, creators want more than accelerated delivery: they want to monitor, control, and be compensated for content consumption. Cost-effective global distribution requires content "internetworking" between players—not just within a single CDN, but between CDNs. This is the genesis of "content peering".

Content bridge
In his iBAND keynote, Adero Senior VP Alan Fink cited three problems with today's independently-operated, proprietary CDNs: scalability, trust, and freshness. Simply put, a cooperative network of CDNs should be able to reach further than any individual CDN. "Today's CDNs break down when an ISP puts a cache in front of their customers," said Fink. "The content provider loses control of delivery." Edge caches that are not part of the CDN cannot be trusted to ensure freshness, log access, or deliver contracted quality of service.

The Content Bridge solution: bring access providers and their edge caches into the fold.

According to Fink, Content Bridge ensures that all participants are compensated for their role in the content delivery chain by providing a framework for cooperation between content creators, hosters, carriers, and access providers. By employing open interfaces and a central clearinghouse operator (Adero), Content Bridge enables guaranteed, predictable performance and reliability from content creator to consumer.

"In our model, ISPs collect revenue based on hits (content delivered)," said Fink. The hoster bills the content creator, retains a portion as its revenue share, and forwards the remainder to Adero. Adero, responsible for monitoring, logging, traffic reporting, customer support, and billing, allocates revenue to access providers. With this new revenue stream, ISPs are incented to retrieve fresh content and log usage. But, without last mile visibility, how would Adero ensure that hit counts represent actual delivery? Fink didn't have an answer for this one—yet.

Content Bridge members include Adero, America Online, Digital Island, Exodus, FastForward Networks, Genuity, Inktomi, Madge Web, MirrorImage, and NetRail. "We support Content Bridge as an industry initiative because it ultimately promises to improve the performance and end-to-end quality of service of the Internet while enabling us to offer our customers additional benefits within the Exodus/MirrorImage three-tiered content distribution model," said Exodus CEO Ellen Hancock.

"We intend to connect our Overnet to ISPs under the umbrella of the Content Bridge in order to offer optimal content delivery to home-based users," said Robert Madge, Madge Web CEO. "This will benefit both our hosted clients and those using our streaming media services."

Working with these providers to propose content peering standards are Technical Advisory members Alteon WebSystems, Apogee Networks, Compaq, HP, Intel, Portal, StorageNetworks, Sun, and Vignette. In November, Content Bridge submitted Internet Drafts entitled "Origin/Access Content Peering for HTTP", "Cross-Network Accounting for HTTP", and "Cross-Network Distribution of Content Signals for HTTP" for consideration by the IETF.

Go to page 2: Content Alliance, and conclusion