Flex Systems Get New 10GE And 40GE Switches, Too
August 12, 2013 Timothy Prickett Morgan
In addition to the three new Flex System server nodes that are discussed elsewhere in this issue, IBM also announced three new switch modules that slip into the back of the chassis and offer connectivity between enclosures and across racks of enclosures. (The number three is just a coincidence and there are no dependencies. Although three is, of course, the magic number.)
The first new switch, which you can see in announcement letter 113-125, is called the EN6131, and it is a based on the Switch-X Ethernet ASICs from Mellanox Technologies. This switch has 14 internal ports that run at 40 Gb/sec speeds running the Ethernet protocol (these are done mechanically through mezzanine cards on each server, which hook into the Flex System chassis midplane, which in turn the switch plugs into. The EN6131 has 18 ports that come out of the switch module that run at 40 Gb/sec speeds plus one 1Gb/sec Ethernet port for management. The switch has an aggregate throughput of 1.44 Tb/sec and can do a port-to-port hop in 700 nanoseconds. That makes it a very low latency switch, and explains why it costs $34,999.
Here is how the EN6131 stacks up to the other five switch modules available for the Flex System chassis:
As you can see in this chart, the other new switches are the SI4093 and the EN4093R, and both are modules with 10 Gb/sec internal ports and either 10 Gb/sec or 40 Gb/sec uplinks. The SI4093 is a scalable switch, which comes with fourteen 10 Gb/sec internal ports (one for each node in the Flex System) and that can be doubled up to 28 internal ports. It has ten 10 Gb/sec uplinks to the outside world and you can add two 40 Gb/sec uplinks if you need more oomph. This module can also be set up as a pass-through device, so the core network just sees the traffic coming out of the chassis as one “large pipe” of server traffic, as IBM put it. The SI4093 costs $9,499, and adding the extra ten internal ports costs $7,599 while adding the 40 Gb/sec uplink ports costs $9,499. This switch is designed by IBM and it is not clear what ASICs it uses.
That leaves the EN4093R, which is getting a firmware update so it can support the OpenFlow protocol. OpenFlow is a new network virtualization technology that separates the network control plane from the data plane and allows the control plane to be altered programmatically based on traffic conditions on the network rather than by human beings messing around with settings in firmware. This switch also offers the same port combinations as the SI4093.
OK, so that was really only two new switches and a tweaked existing one.