Digital utility is a wise approach, says consultant

According to Kevin Tolly, president of The Tolly Group in Manasquan, N.J., enterprises should try to move to a new approach with their LANs and build a digital utility to “power Information Technology in much of the same way that the traditional power grid does that job today.”

Tolly was a keynote speaker and moderator at a seminar presented by Network World (US), called State of the LAN: Implementing the New Best Practices. The event was held in Toronto last month, and was the tour’s only Canadian stop.

Panellists at the event included spokespeople from Alcatel, Marconi, Avaya Systems, Extreme Networks, Alteon Web Systems and Hubbel Premise Wiring. John Gallant, executive vice-president and editorial director for Network World (US) was also present as a moderator.

The seminar addressed what needs to be done to build and improve the state of campus local area and metropolitan areas networks.

In his keynote speech, Tolly noted that “we are already well on our way to” the digital utility approach, and listed some givens, including traditional LAN data, training video and telephony.

“These are things we can do already today – where we can converge multiple, different types of applications,” he said.

The prospects in these areas include things such as building security, management and environmental systems.

“With all of that activity, all of these control systems and elements have to communicate in some way, shape or form,” he explained. “Why should it have to be across separate networks when it could all happen across one network?”

Tolly said the rationale behind the implementation of this utility comes down to several things, including massive economic benefits. And while the potential to save and make money is there, that is not the main reason why network managers should consider this approach.

“The primary rationale is to be able to have this launching pad for new applications that were previously unthinkable,” Tolly said.

He went on to explain that a digital utility is composed of several elements, and the most important is a TCP/IP network, which is more unifying than Ethernet.

“TCP is what allows us to run data transfers larger than 1,500 bytes, a restriction imposed by Ethernet standard,” he said.

But Ethernet is included in another element cited by Tolly, which is that the TCP/IP network should run over Ethernet, or SONET and other transports. In this sense, Ethernet is very cost-efficient and ready, he explained.

The delivery of quality of service (QoS) is another important element, and was addressed several times during the seminar by panellists and attendees.

“It may well be that few, if any of you, are running any type of QoS on your campus today,” Tolly said. “That’s fine. You may be able to run for quite some time that way, but the real key is that the operative word is ‘may.’ It ‘might’ work. You ‘may’ be able to do it. (But) if you’re moving to a digital utility, you really have to guarantee it.”

He stressed that as enterprises move towards a converged network, where there might be very critical latency-sensitive traffic jitters such as real-time voice, without any type of QoS, they might be okay, but they certainly will not be able to guarantee it.

Other elements that define a digital utility are that they are fault-tolerant, fluid and proactively manageable, according to Tolly.

Something else to consider when it comes to a LAN, he said, is that there are several technologies network managers should avoid altogether.

“You should avoid technology dead-ends,” Tolly noted. “You should try to make sure that everything you do today can take you some place.”

For example, he explained that virtual LANs (VLAN) should be avoided in the enterprise, but admitted later on in the seminar that they would be recognized as something that could help to solve problems.

“The interesting thing with VLANs is that we’re not really using them the way that they were designed for. The need that they were designed to fill was…primarily of separating traffic in a shared network,” he said. “And by the time VLANs got to a point where they were at a high level of acceptance, that need had really gone away.”

While Tolly explained that VLANs are still helpful, most of the panel agreed that they are not really needed anymore for their original use.

Another thing to avoid, according to the panel, is a poor-quality cable infrastructure.

“Every one of us up here on stage believes that we should be building switched infrastructure,” Tolly said. “And everything we’re talking about – implementing QoS, implementing packet voice, whatever you might mention for the digital utilities on campus, taken from the fact that you have dedicated connection and you can control bandwidth to and from each station – you can’t do that from a shared-hub environment.”