Juniper Updates its Switching Fabric

Juniper Networks last week announced several enhancements that extend its QFabric networking platform to 40-Gbps nodes at the high end and to cost-effectively support mid-tier networks. These improvements promise to allow the use of Juniper's low-latency switching fabric into a wider range of applications.

The new QFX3000-M QFabric System extends the QFabric architecture into smaller data centers and even branch offices with a footprint that takes up 63% less space than competitive routers. A new 40-Gbps node can increase the maximum bandwidth for high-performance servers connected to the QFabric platform. In addition, Juniper announced the EX8200, which is designed to extend the reach of a data center switching fabric up to 80 km over dark fiber, allowing its use in multicampus deployments.

Juniper's QFabric uses a proprietary interconnect for moving packets between multiple servers in a data center. Denise Shiffman, VP of enterprise systems marketing at Juniper, says this approach reduces overhead associated with processing IP packets and simplifies the management and configuration of I/O modules used to connect to the fabric.

"We provide redundancy and a single point of management for an entire 6,000-port switch or network, whereas in other solutions in the marketplace, you have to touch each of those devices," says Shiffman. "As much as 70% of the cost of running a data center comes from managing the network."

Using an interconnect also reduces the amount of packet processing involved compared with a traditional IP-based switch. The smaller QFX3000-M can keep latency down to less than 4 microseconds. "In a traditional architecture, every switch has to do the same repeated packet processing on each hop," says Shiffman. "Other vendors are rewriting protocols on how switches talk to each other. But we think there is no way to get the latency down to 5 microseconds or less using this approach."

The main benefits of the QFabric interconnect are high capacity throughput and, more importantly, deterministic latency. QFabric can create large, Layer 2 networks that fit well with existing requirements for virtualized environments and larger scale data centers.

The QFabric will initially be most attractive to those with large-scale interconnect or low-latency networking needs including larger data centers, service providers and financial services organizations, says Eric Hanselman, research director, networks, at 451 Research. "In the enterprise, QFabric could deliver value in virtualized data centers. Many live workload migration technologies [such as VMware's vMotion] and Microsoft's clustering functionality were designed with an expectation of high-performance, Layer 2 connectivity, an area where QFabric can excel."

But this new switching interconnect faces challenges from enterprises used to IP-based switches. Hanselman says, "There have been concerns expressed about the proprietary nature of the interconnect. While it's certainly proprietary, competing offerings all have some level of vendor-specific implementation."

To address these challenges, the Internet Engineering Task Force has been working on the Transparent Interconnection of Lots of Links specification to create a path for multiple link interoperability. However, no vendors have followed it to true, full functionality and a vendor-agnostic interconnection. "All of the existing implementations lose some capability when making the transition across vendors," says Hanselman.

In the longer term, he sees the greatest potential for leveraging interconnects with direct integration into applications. "Juniper is looking to tackle this with Junos Space's integration with virtualized networking capabilities across its product line," he says. "As with other vendors, there is much work going on in this direction."