Cisco vs. Juniper Episode II: Enterprise Switching

I don't know if anyone noticed, but Cisco and Juniper announced some new switches a few days ago. Anyway, Network World has asked me to comment on these switches, so here are some initial thoughts.

Cisco and Juniper have been going at each other all-guns-blazing for years in the service provider market, but until now there have only been limited skirmishes in the enterprise market. Now that Cisco has announced its Nexus switching platform, and Juniper has finally unveiled its EX switches, I think it is safe to say that we can expect renewed and greatly intensified hostilities in the enterprise market.

So, how do Cisco's Nexus and Juniper's EX switches compare?

Well, the first thing to say about the Nexus 7000 and EX switches is that comparison is not straightforward. Juniper announced several models including 3200, 4200, and 8200, but Cisco only announced a single model, the Nexus 7000. The Nexus is targeted for a specific role, while the EXs seem to be more general switching platforms which can used in branch, campus, or data center networks. Only the Juniper 8200 seems comparable to the Nexus 7000.

The specific role that Cisco has in mind for the Nexus is the (large) data center. However, apparently we shouldn't expect to see things like a firewall services module for the Nexus. Also, it seems that there won't be any support for MPLS on the Nexus, though it will be supported on the EX switches.

Some other areas of differentiation between the new Cisco and Juniper switches and strategies that have caught my eye include performance/scalability, virtualization, operating systems, network unification/convergence, and overall vision for the enterprise.

On the performance/scalability front, the Nexus 7000 provides support for 10Gbps Ethernet, and will in future support 40Gbps and 100Gbps Ethernet (IEEE 802.3ba). The Nexus will support 8Tbps of switching capacity initially (10 slot Nexus 7000), with 15Tbps in future (18-slot Nexus 7000). It is worth mentioning that the Nexus won't immediately support 40Gbps and 100Gbps, however -  IEEE 802.3ba is not ready yet, and it's not expected for a couple of years. So, initially at least, buyers will just have to content themselves with 10Gbps!

The EX 8200, on the other hand, will be available in 8-slot (1.6 terabit) and 16-slot (3.2 terabit) models, and will support port speeds of up to 10Gbps. Juniper doesn't mention future support for IEEE 802.3ba.

Now, on the face of it, the Nexus has got a healthy advantage over the EX 8200 in terms of switching capacity. But unsurprisingly, the numbers are in dispute, with Juniper CEO Scott Kriens claiming that the Cisco number is simply an aggregation of port speeds, while the Juniper number is a measure of forwarding performance.

Cisco and Juniper are both trumpeting virtualization as a feature of their switches, but their approaches are quite different.

The Nexus offers virtualization in the form of Virtual Device Contexts (VDCs). VDCs offer the ability to create virtual switches, with dedicated software processes, dedicated hardware resources, traffic-isolation, fault-isolation, and separate management. Network device virtualization is not a new concept, of course, but it looks like it will be a very useful feature on the Nexus.

Juniper, on the other hand, is promoting the fact that the EX 4200s offer ‘Virtual Chassis' technology. The Virtual Chassis technology allows up to 10 EX 4200 switches to operate as a single system. At first glance, this may appear to be a sophisticated form of switch stacking,, well, I'm not really sure what else it is. I am sure that any Juniper folks reading this blog will let me know how their technology is different!

One area that Juniper seems to have identified as a competitive advantage of their switches is the fact that they have a single operating system (JUNOS) for their routers and switches. Cisco, on the other hand, has chosen to create a new Linux-based OS (NX-OS) for the Nexus.

While NX-OS is new, Cisco says that we shouldn't worry, because it has similarities to both IOS and SAN-OS. When I related this to a sample group of (admittedly grizzled and somewhat cynical) network engineers, it did provoke some feelings of dissatisfaction. It even elicited an expletive or two. Perhaps Cisco would have been better just calling their new OS ‘IOS-NX' or similar. And if my totally unscientific survey of engineers is anything to go by then Juniper's decision to use JUNOS on their EXs is going be met with some favourable reaction.

So much for performance/scalability, virtualization, and operating systems. But how about Cisco's claim that the Nexus will help customers unify and simplify their networks? And what do the Juniper EX switches offer in terms of network unification?

Just in case you were unaware, the Nexus is going to support both Ethernet and storage network connectivity, and will therefore allow you to unify your networks. But the Juniper EX switches do not support storage networking. So, a clear difference and, if you like the idea, this feature is a clear advantage for the Nexus.

Having said all that, you should be aware that storage networking support on the Nexus is it not likely to happen for a while. The storage networking capabilities will be based on Fibre Channel over Ethernet (FCOE), which hasn't been standardized yet. It's also worth mentioning that the Nexus will not support Fibre Channel or Infiniband.

As far as vision and strategy are concerned, Juniper sees the commonality of OS across their router and switch products to be a major advantage. They say that the EXs will help to reduce complexity, and will help to provide better reliability, performance, and security. They also emphasize their partner relationships with companies such as IBM and Microsoft.

The Nexus, on the other hand, is integral to Cisco's Data Center 3.0 vision. So, if you think agree with Cisco that the data center network is going to have to be more resilient/highly available, that it is going to have to better enable the virtualization of services and resources, and that it is going to have to be highly scalable (among other things), then you are probably going to see the Nexus as the ideal switch.

As it stands right now, I personally think that this Cisco vision will be more appealing to enterprise customers. Juniper's vision for the enterprise seems just a little lacking right now in comparison to Cisco's, but no doubt Juniper will be fleshing it out in the coming months.

So, what do you think of the Nexus and EX switches? Please feel free to comment...- just keep it friendly, folks!


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