Juniper merges network core elements to cut carrier costs

Its PTX switches, coming next year, combine optical and packet switching

Juniper Networks is developing a massive switch that could replace traditional IP (Internet Protocol) routers in the core of service-provider networks and combine optical and electronic technologies that today exist in separate systems with dedicated staffs.

The PTX Series Packet Transport Switch platform, of which the first products will ship in the first quarter of next year, will combine two technologies that carriers use to bypass routing at the center of their networks. Routing involves the processor-intensive work of examining every packet, and it often isn't necessary for traffic that is just traversing the core of the network. Instead, carriers use MPLS (Multiprotocol Label Switching) and optical switching, neither of which requires full routing intelligence, to move traffic through the core.

The PTX platform combines these approaches in the same box and is not designed as a router at all. Juniper wants to relegate routers to the edges of the network and devote the PTX chassis to switching. This will allow the company to focus the processing power of the new system on the tasks required of the core, Juniper said.

Carriers are under pressure to boost their network capacity to handle fast-growing traffic loads. They want to do so economically, because they continue to bring in about the same amount of revenue from their subscribers even as third-party service and content providers deliver more bandwidth-hungry offerings such as video, analysts said. By optimizing the PTX for switching instead of routing, and integrating optical technology into the same chassis, Juniper may cut carriers' costs while bolstering their network capacity, they said.

For enterprises and consumers who buy services from carriers, this might mean a slower rise in their monthly bills or better services for the same rates.

"Because of some of this cost being reduced ... you would hope that this kind of reduces the cost per bit and therefore is passed down to the IT guys," said analyst Ray Mota of ACG Research.

Adding optical switching to a packet switch brings Juniper into a totally new market and could dramatically change carriers' network operations over time. Today, carriers feed packets from their core routers into a separate optical infrastructure, which places the traffic on separate wavelengths of light for fast transmission. The traffic needs to be converted from the electronic to the optical realm, and then back again on the other end of the network. Putting both in the same chassis simplifies the network and removes those costly conversions, while also making it easier to scale up the infrastructure, Juniper said.

The company claims the PTX platform can cut network capital expenditures by between 40% and 65% compared with a traditional multiprotocol routing architecture and by 35% compared with an IP-only routing system.

The announcement of the PTX sets Juniper on a new architectural path for the second time in just two weeks. Last Wednesday, the company unveiled QFabric, a converged enterprise network platform that creates a single logical switch throughout an entire data center. Like the new carrier-network infrastructure, QFabric is designed to eliminate multiple layers of switches and reduce the number of required devices. The overall architecture, which Juniper calls the Converged Supercore, will also include ROADMs (reconfigurable optical add-drop multiplexers), management systems and other components, Juniper said.

The promise of the PTX systems also will change the role of the T4000, a traditional core router that Juniper announced last November and is not even scheduled to ship commercially until the fourth quarter of this year. A PTX switch will be able to take the place of a T4000 in the cores of networks, offering greater throughput and efficiency. In such an architecture, the T4000 would be Juniper's option for the edge of the network, where it can also carry out high-end functions such as service management along with routing.

"I was impressed that [Juniper] took the step of competing with themselves and other core router companies by building this MPLS switch," said analyst Michael Howard of Infonetics Research.

Each slot of the PTX switch chassis has double the 240G bps capacity of a T4000 slot, and its initial 480G bps slot capacity can be expanded to 2T bps. The PTX line will start out with two systems, the PTX 5020, with a total capacity of 8T bps, and the PTX 9020, with 16T bps. The architecture ultimately will be able to scale up to 32T bps, which Juniper said is 10 times the scale of competing products. Among the interface line cards available for the PTX switches will be four-port 100-Gigabit Ethernet modules, a step up from the one-port or two-port 100GE cards that other vendors are offering today.

Many carriers have been looking for pure MPLS switching for their network cores, according to Howard. In addition, large carriers maintain separate staffs of engineers for optical and electronic switching, as well as separate management systems, and they want to converge those infrastructures eventually, Howard said. The PTX switches could allow those big carriers to consolidate their staffs over time, he said. Those struggling with the most exploding traffic are looking to consolidate the technologies in two or three years, while others may take five to eight years, he said.

Juniper has a reasonable shot at getting into the optical equipment market, currently served by rival Cisco Systems as well as specialists such as Ciena, Mota of ACG Research said. He estimates the company's optical revenue opportunity at $2 billion per year.

Stephen Lawson covers mobile, storage and networking technologies for The IDG News Service. Follow Stephen on Twitter at @sdlawsonmedia. Stephen's e-mail address is

Copyright © 2011 IDG Communications, Inc.

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