Ray Take a look at the lead story on WWW.internettelephony.com. The last part deal with some "heavy" routing issues.
Driving the terabit home
Iron keeps getting bigger and bolder, but are the networks ready for it?
LIANE H. LABARBA
A loud crashing sound breaks the monotone hum of network gear and cooling systems. And in the aftermath of the dust that floods the once pristine control room, engineers scramble to find the root of the commotion. What could possibly have caused such a disaster? A bomb? A faulty design in the building?
The disaster could be the fault of progress.
Although no one likes to name names, many service providers joke about the rumor that one of the new heavyweight (no pun intended) terabit routers fell through the floor because it weighed so much. And from the tales told by service providers and currently unvictimized vendors, the nickname "big iron" may be well-suited for the greatly hyped terabit routers.
Although many terabit routers have problems with weight, service providers still are taking a long, hard look at the equipment. With heavier demand placed on networks, service providers must find ways to add more scalability and brawn to keep up with it. The terabit router appears to be one way to quench the thirst for more capacity, but the question is, are those capacity-hungry networks really ready for the terabit?
More, more, more
As service providers deploy innovative equipment to help them stay ahead of current network demands and meet future ones, the nudges they give to vendors to turn out bigger, better and faster equipment never cease.
In some cases, vendors are developing technology first and then finding a market for it later. But with terabit routers, there is little question that many of the nudges are coming directly from service providers looking to improve their networks. Simply put, they want more of everything.
The list of service provider demands is long and varied, but if vendors can turn requests into results, finding customers shouldn't be difficult. Naturally, the call for bigger routers has captivated the standard network equipment vendors and has given birth to a multitude of start-ups looking to feast on the future needs as well.
Currently Cisco Systems dominates the router market, but the entry and success of start-up Juniper Networks has given hope to other start-ups: Avici Systems, Charlotte's Web, Foundry Networks, Ironbridge Networks and Pluris. More start-ups are expected to surface within the year (Table 1).
And although the start-ups face a challenging fight against incumbent Cisco, Juniper is proving that smaller vendors can break into networks, too--if their equipment fills service provider needs (Figure 1). Within the past two years, Juniper has managed to take a small but healthy bite out of the core router market that is dominated by Cisco.
In fact, some carriers already are finding a need for core applications.
"We absolutely need bigger routers in the core," says Andy Wright, chief technologist of optical networks at Williams Communications. "Core applications like videoconferencing are becoming more popular and are pushing the demand on the core of networks up."
Today, Williams is using packet over Sonet at OC-192 line rates, although it doesn't have a terabit switch core.
"Sonet will tide us over until those come in," Wright says.
With estimates that bandwidth is growing tenfold every year, that network strain should be guaranteed and is most likely imminent for service providers.
"We recognize the need to increase the capacity of current routers," says John Riedel, vice president of global platform engineering for UUNet. "The network has to be able to grow and scale to meet our future demands."
The terabit router acts as one stepping stone to the next generation architecture, Riedel says. But other elements also are necessary to create the rocket-like networks that service providers seek. The high-speed routers must be used in conjunction with dense wave division multiplexing (DWDM) and high-speed fiber links to concoct the so-called next generation networks. And with the introduction of new network elements comes the need to tightly integrate the equipment to work together seamlessly.
And it's not just a capacity issue: Integration is also key.
"The demands on the core are really basic," says Raj Mehta, an analyst with RHK. "Just because you have a core router, it doesn't solve all the problems; all the other elements have to work in tandem."
Williams' Wright agrees.
"Just as we need more capacity, we need more synergy, too," Wright says. To try to add more synergy, Williams is looking at "companies with innovative strategies to provide more integration," he says.
For providers looking into or deploying terabit routers, much of that integration stems from the interoperability of the terabit routers with other network elements such as optical cross-connects.
Williams is testing equipment from Avici. The company is expected to make a significant investment in Avici at the time of its upcoming IPO. Enron Communications and AT&T also are testing the Avici Terabit Switch/Router (TSR), says Peter Chadwick, vice president of product management for Avici.
Lucent Technologies bought its way into the terabit router market with the purchase of Nexabit Networks.
"We succeed by tailoring [the] product to individual service provider needs," says Ram Krishnan, director of internetworking for Lucent's IP group.
Texas-based service provider VCities is deploying Lucent's NX64000 in its network. VCities was attracted to the router's port density, switch fabric and quality of service (QOS), says Russ Medina, CEO of VCities. "With the terabit router, we will be able to make a difference in the marketplace." In addition, VCities had already deployed equipment from Lucent in its network, so interoperability was not an issue, Medina says (Figure 2).
Juniper, Avici and Lucent don't have a stronghold on the terabit router space, however.
"Avici is at the front end of the technology curve, but we are working with a number of other vendors, too," Wright says. Williams also is testing equipment from Corvis, which recently announced an interoperability partnership with Avici. Avici also is working with optical cross-connect vendor Tellium.
"We have to be interoperable with existing network elements and try to take a more active roll with future elements like the optical cross-connects," says Chadwick.
UUNet's Riedel agrees with the interoperability push. "We have to get the router guys to talk to the optical guys. We look at not just a piece but the whole pie, and all of the elements have to happen together to make it work."
Bricks on the iron road
As vendors get closer to timing product releases with service provider needs, the rollouts are heating up.
UUNet announced earlier this year that it will deploy Juniper's M160 backbone router, which is the first box to move traffic at 10 Gb/s. The M160 carries a maximum capacity of 160 Gb/s, which is four times that of its predecessor, the M40.
UUNet has deployed Cisco's GSR and Juniper's M40 routers in its network and plans to replace several of the GSRs with the beefier M160s.
Cable & Wireless and KPN Qwest also are deploying the Juniper routers.
Although UUNet is rolling out the Juniper M160s, the provider maintains that it is important to use equipment from more than one routing vendor.
"We value having more than one supplier," Riedel says. "We really like to have more than one and less than three. We can't be limited to one vendor if there is some kind of dark undiscovered flaw."
The Avici TSR is attractive to Williams because it uses striped trunking, Wright says. That technology, which Avici refers to as "composite trunking," essentially enables service providers to clump devices together so they act as one entity, rather than several separate ones, which has been the status quo for increasing capacity so far.
Pluris also supports a similar technology although they refer to it as "IP bonding," which creates the same results, says Michelle McLean, director of strategic marketing for start-up Pluris.
But while clustering may boost performance, traffic is forced to go through numerous hops, which burns capacity. Therefore, it gains capacity while it also loses some capacity.
"Both our product and Avici's are designed to interconnect," says McLean. "We both use switch capacity [through the fiber ports] for the interconnect."
Cisco is also working on its multiple router approach to meet the need for speed. "With the GSR 12016, we can put multiple [routers] together and interconnect them to reduce the number of paths," says Kelly Ahuja, director of marketing for Cisco. "We essentially can interconnect modules without burning I/O ports."
Pluris' box will use fiber optics on its backplane once it is available, whereas Avici uses copper, McLean says (Figure 3).
"The copper gets problematic," McLean says. "Weight really becomes a problem,".
The biggest benefit to the fiber backplane is that when "you roll up a second one, you can set it 400 feet away," McLean says. "The Avici equipment has to be hard bolted between two chassis, so the provider must leave contiguous space to accommodate for it."
Iron's softer side
Switch capacity, interconnection and interoperability are key factors to a service provider's deployment decisions, but perhaps the more sensitive issues are that of software reliability and scalability. To break into the core router market, prospective vendors must develop software capable of routing traffic flawlessly in a highly sensitive area of networks.
"One of the biggest challenges has been software," Mehta says.
Juniper is trying to knock Cisco off its market leading pedestal by taking a page from Cisco's playbook--add value in the software. Juniper's Junos software has remained almost identical since the company released the M20.
In many cases, the service providers can get their hands on the equipment and software while it is still deeply entrenched in the development phases. That was the case with the Juno software and UUNet.
"Providers such as Avici are planning on these big, fast routers, but it isn't just about building a router that goes fast. It's about stable software, having tech support and a vendor that works with us as the network grows," Riedel says. "We also have to look at things like if the vendor can do all the service support we need over holidays, for example."
"We give the software [to service providers] early so they have a lot of time with it," Pluris' McLean says. "For a long time it was just Cisco, but things have definitely changed. Juniper gets a lot of credit for their software."
"[Junos' software] is a really good, solid technology," says John Stewart, marketing engineer at Juniper. "People like Juniper because we are giving them a choice, and it is something to compete with [Cisco's] IOS ."
As Juniper seems to be reeling in contracts, more traditional vendors are finding it wise to partner with the start-up rather than move forward with a gaping hole in their portfolios.
Alcatel, Ericsson and, most recently, Nortel Networks have teamed with Juniper to help meet the immediate needs of customers. While those companies claim to have internal developments that are either stalled or still in progress, Juniper's equipment is ready today.
Ironically, Nortel owns roughly a 17% stake in Avici after the two companies severed ties earlier this year. Still, Nortel has partnered with Juniper.
"Juniper has the product with the highest density of OC-192 pipes, and it is purchasable, deployable and ready to work today," says Alan Raderman, senior director of marketing for data, broadband and optical networks at Ericsson.
While being late to market is not the best way to break into a new space, it is reality for some. However, some don't consider that a hindrance.
"We have had the benefit of having Juniper out first," says McLean. "They woke up the world to the fact that service providers have a choice and will use another product besides Cisco."
On the flip side, those providers and Juniper now have the task of offering more than just a second source to Cisco. Latecomers are turning to factors such as operating systems and reliability to get their foot in the door.
The real issues behind the core routers have to do with things such as carrier-class reliability and QOS, Raderman says.
Avici is trying to focus on scalability, not just router performance, Chadwick says. By allowing customers to add capacity in a non-disruptive manner over time, customers can take advantage of new technology developments coming out of the optical space, Chadwick says. "Non-disruptive scalability is what we have in mind."
Behind the veil
Terabit routing has definitely seen its fair share of hype and glory, and by the looks of things, those days are not over. But with all the talk of demand, trials, deployments and promises, does a true terabit router exist? And if it does exist, do service providers actually need it just yet?
There is no way terabit speeds could be achieved in one system; multiple systems are needed, Stewart says. "There isn't a terabit [capacity] router shipping today. Too much attention is being paid to the switch fabric."
Large-scale deployment of OC-192 in optical networks is still about two to three years out, so the need for a terabit today is not necessary, Raderman says. "Since the terabit isn't really the issue, what if the router does, say, half as much?"
RHK's Mehta agrees. In the near future, multigigabit devices will be needed, but those infamous terabit speeds won't be necessary for about another three years, he says. Metra predicts that the core router space will become a $12 billion market within three years.
While the terabit speeds may not be necessary for some time, service providers still maintain a "the sooner the better" attitude with the new routers.
And if a provider can deploy equipment capable of scaling to future demands and keeping network costs down, chances of success will be even greater for the self-proclaimed terabit router as it strives to live up to its name.
RETURN TO TOP
--------------------------------------------------------------------------------
Tipping the scales
Liane H. LaBarba
Terabit routers are breaking speed barriers previously not met by older equipment, but along with that speed comes additional weight. Most central offices or points of presence are built on suspended floors to accommodate cabling and ventilation systems below, so the need for a terabit diet is evident, especially after the rumors of one falling through the floor.
Because of the weight issue, several providers such as Avici Systems are building special platforms to support the routers.
Avici has a weight problem because its Terabit Switch/Router (TSR) uses a copper backplane, which becomes heavy and potentially bows under its own weight, says Michelle McLean, director of strategic marketing at Pluris. To remedy the problem, the vendor attached reinforcements to prevent buckling, but that solution only compounded the weight problem.
"I don't know that [copper] does create a weight problem," says Steve Duffy, product line manager at Avici. "We chose copper because it was more cost-effective from a component and operations standpoint." The copper drains less power than optical fiber and creates less heat, Duffy says.
But others maintain a problem exists.
"On top of the falling through the floor stories, these things can be like a little Chernobyl," says John Riedel, vice president of global platform engineering at UUNet. "They bring up all sorts of concerns about power [consumption] and heat [exhaust]," he says. "Suddenly service providers are finding themselves pondering chilled water to cool things down." |
