JUNOS Enterprise Routing

What Is Enterprise Routing?

After you’ve spent some time in the networking field, you tend to notice that there is rarely a single way to do things, and in many cases, a single precise definition for terms. After all, often a network engineer’s best answer is “it depends.” Such is the case with enterprise routing, so let’s start off with a definition question: what is an enterprise network? Is it a large multinational network used by a manufacturing company; is it a government network supporting a state or a county; is it a regional network used by a parts distributor; or is it a network that supports your local dentist’s office?

Of course, it’s probably all of these, and many more. At a very high level, you can state that an enterprise network is one that is used to support activities as opposed to generating revenue, as in a service provider’s network. Some might say that if someone pays you to access your network, you are providing a service to him and you’re no longer an enterprise network. But that sweeping statement doesn’t really apply if that someone is paying you to cover your costs to provide that service. So, as you can see, it depends.

Defining an enterprise network also manifests itself into how Juniper Networks defines its products within the enterprise world. On the one hand, Juniper designates certain hardware platforms as enterprise routers, but then many enterprise networks require density and throughput options from a platform listed as a service provider product. From the software side of things, the same issue arrives. Whereas a technology such as IPSec is used by all types of networks around the globe, is it used more by enterprise networks than by service provider networks? Some engineers would answer yes to that question, but then, you can’t say that a service provider will never use IPSec.

From the perspective of hardware platforms, Juniper Networks has designated the following as enterprise products:

• J-series routers to include the J2300, J2320, J2350, J4350, and J6350

• M7i and M10i routers

• M120 routers

However, larger enterprise networks may find platforms such as the M320 and MX960/480 very useful for their environments. In fact, the reverse is also true in that a traditional service provider network may very well find an appropriate need and use for platforms designated as enterprise routers.

The good news in all this is that you have a well-thought-out operating system in JUNOS. The JUNOS software is a single train of features that operates across all of the various routing platforms. So, whether you run an enterprise network or a service provider network, and regardless of your actual hardware platform, there is a single version of software code to load. Although this single code train has lots of hidden benefits, such as stability, ease of expandability, lower total operational costs, and more, what it really means is the ability to have the same features available on all devices. So, from a learning perspective, we can talk about the software and its features without having to constantly caveat our discussion with “except for on this platform” or “only on these particular platforms.” Although such exceptions do occur, and they result from hardware enhancements that are unique to a particular platform, these cases tend to be exceptions and are infrequent enough to remember.

Throughout this book, we will attempt to simplify the discussion by limiting ourselves to the J-series platforms and the M7i router as we discuss the various features and options available to configure. We also focus on those topics that the vast majority of enterprise networks care about and actually use. We will also define an enterprise network as one that uses an Internet connection as opposed to a network that provides connectivity to the Internet as its sole function.