Weaving intelligence into network hardware is every bit as crucial as adding bandwidth in building converged, next-generation networks.
That was the crux of the message delivered to NetWorld+Interop attendees in Las Vegas last month by Cisco Systems Inc. chief technology officer Judith Estrin at one of the event’s featured keynotes.
Over the last 20 years, the most common device in the data networking world has been the PC, Estrin said. While the PC will continue to play a key role in the future, other data appliances such as Internet phones and car consoles must be accommodated by networks as users seek more mobility.
“The Web phone will be one of the most ubiquitous devices on the network,” Estrin predicted.
Because mobile devices such as Web phones won’t be able to carry as many features as a desktop PC, some of the PC’s intelligence must be embedded into the network. The network must become user-aware and application-aware, Estrin said, adding this can be achieved through the deployment of policy and control services tied together by directory services.
Added intelligence is also necessary to ensure Quality of Service (QoS) in converged telephony/data networks.
“It’s obviously key for telephony,” Estrin said. “And the intelligence must be in the devices in the queuing mechanisms. It’s not enough to layer it on top.”
The second key to building next-generation networks will be increasing the available bandwidth, Estrin said.
In the core this will be accomplished by the spread of optical technologies such as Dense Wavelength Division Multiplexing. Over the so-called “last mile” to consumer and work-at-home users, cable, wireless and DSL will provide fatter pipes.
“I’m often asked which of them will win and I respond either, all of them or none of them,” Estrin said.
Each technology has a role to play in certain geographical areas and that role will depend on existing infrastructures and telecommunications regulations, she explained, adding that competition between the three technologies should benefit the deployment of all of them.
Estrin likened what is currently happening in the telephony world to the move from a mainframe model to a distributed model in the computing world. Telephony networks are evolving from their roots, which were based on centralized, proprietary, circuit-based switches, to distributed, open, packet-based architectures.
What’s driving the move to next-generation networks is their ability to handle new types of applications.
“It’s not about the cost per bit,” Estrin said. “It’s about doing things in new ways.”
Many companies already have converged WAN links carrying both voice and data, Estrin noted. She predicted LAN switches will begin to transform into LAN PBXs over the next 12 to 18 months with the killer application being call centre software featuring voice and data capabilities.
Estrin attempted to dispel the well-entrenched notion that the telephony infrastructure is inherently more reliable than the data infrastructure.
Existing telecommunications networks rely on point-to-point connections, she said. This means they have a single point of failure and therefore must rely on robust, scalable voice switches to prevent breakdowns. Data, on the other hand, relies on clouds of distributed devices, so it doesn’t have a single point of failure.
However, Estrin explained data technology must mature. Among the features needed are faster fail-over capability, QoS and security. Estrin said these functions will appear in time, noting that telephony networks didn’t reach the state they’re at now overnight.