The world according to Milo

The contract extensions that AT&T, Cox Communications and Comcast signed with Excite@Home late in March apparently have settled the question of whether the cable ISP will have a business when its exclusive agreements with those multiple systems operators end in mid-2002 (see profile on page 28). But the three cable partners also have promised that some day consumers can call an unspecified number of independent ISPs via their networks. So the problem now is, how will that work?

Signing contracts doesn't make technical problems disappear, and accommodating third-party ISPs after 2002 will take some re-engineering of the @Home network, said Milo Medin, @Home founder and chief technical officer of Excite@Home. "The cable network is a shared network, and I think that's a good thing."

The Internet also is a shared network, and because most people's use of the Internet is bursty, having multiple people share a fatter pipe delivers a more satisfying experience, he added. "But the downside is: If you have multiple service providers, how do you keep them out of each other's knickers?"

Excite@Home has spent capital and energy optimizing its network for delivering content, Medin said. The company operates a national infrastructure with a dual OC-48 IP backbone, consisting of a series of long-distance fiber rings leased from AT&T. This backbone links multiple network access and peering points to Excite@Home's "super nodes," located in metro areas and used as service hubs that cache, monitor and host content close to the subscriber.

This cable Internet system works most efficiently with one ISP and one set of customers. "If we had two ISPs, the simple way of doing it would be to cut the bandwidth in half," Medin said. "While one service provider is bursting at full capacity, the other might have bandwidth available that's not being used. You're introducing inefficiency, and that causes a lot of cost to go into the network because you're burning more spectral resource. How much it goes up, what kind of [service level agreements] you can create for the ISPs so they know what they're getting - all those details depend critically on the architecture of how you're sharing."

Complicating that problem is the fact that one ISP may only want always-on service and 120 kb/s of bandwidth, while another may want to do spectrum-hungry tasks such as streaming media. How do you then price that wholesale service? If you charge by the byte, that will lead ISPs to shift from flat-rate to volume pricing.

"I'm sure that's something the DSL companies would love to see them do," Medin said jokingly. "But I don't think we're that stupid."

At a minimum, Medin said, third-party carriage over hybrid fiber/coax will require changes to the DOCSIS standards for cable architecture - "what kind of tunneling we use and how we do connection setups and whether the tunneling is done at the cable head-end or out of the cable modem," he adds.

Those changes may be executed through software upgrades. Excite@Home is working with the cable industry, cable vendors and CableLabs to develop the needed specifications.

America Online's entry into the cable arena, and the resulting fall-off in open access pressure, gives Excite@Home and the cable industry time to work through the issues surrounding third-party transport. "I don't think there's a regulatory push for us to get this done right now," Medin said. "That's good in a lot of ways because it frees us to concentrate on building products that people want to use."

But AT&T's announcement that it would honor its exclusive contract with Excite@Home out of responsibility to Cox and Comcast no longer applies now that it has no partners, said Rich Bond, co-director of the openNET Coalition.

"The only reason cable companies want to deny consumers choice is to extend their monopoly hold over cable Internet users for two more years," he said, urging the three MSOs to add unaffiliated ISPs this year.

Some problems in adding ISPs to a shared cable system, according to Medin:

- Partitioning bandwidth among service providers with different needs and user profiles

- Streamlining provisioning and other OSS functions while maintaining customer care

- Re-adjusting DOCSIS specs on connection setup, tunneling, etc.

- Finding a transport pricing model that will fit varied ISPs providing varied services