CCNP Lab 9 – ISCW and MPLS

I just forgot. Of all the CCNP exams, ISCW covers the broadest range of topics. When I covered ISCW a few weeks ago, I covered all the main ISCW topics, focusing on the security topics. But I just forgot MPLS. Any interestingly enough, as our survey has shown over the last few weeks, MPLS is one of the topics that more people want to hear about when this series is finished. So, before turning my attention to the bigger picture of what to put in a CCNP lab, I need to post a few comments about MPLS and the ISCW exam.

First, for those of you unfamiliar with MPLS, today "MPLS" is almost as big as saying "IP routing". There are a lot of useful functions provided by MPLS, and lots of familiar features that integrate with MPLS in order to provide those features. There are a lot of books devoted to MPLS, and frankly 1 volume can't cover it all even if the printer uses skinny paper.

All that begs the question - which chunk of MPLS do we care about today for ISCW? In my opinion, I think it's also worth asking the question about what to expect for the next revision of the CCNP exams.

Since we're talking labs here, I'll stick with all ISCW exam topics that require hands-on work. In the current exam topics, and in the authorized course's lab guide, that includes only frame-mode MPLS. With Frame Mode MPLS, the routers use a new protocol (LDP) to exchange MPLS label information about known IP routes, then adding/removing label headers that list those learned labels. It's relatively simple to configure once you know the basics of MPLS concepts.

For the possible next versions of the exams, if I had to guess, CCNP will include MPLS VPN configuration. MPLS VPN concepts are covered in the current ISCW authorized course materials - the course just doesn't include coverage of the MPLS VPN configuration, which can get involved in a hurry compared to just frame-mode MPLS. So, there's some benefit to planning to support MPLS VPN in your lab.

Now, for the good news for labbing: 2600's (non-XMs) support Frame Mode MPLS. (I actually used 2610's as the MPLS core in my lab when writing the MPLS coverage in my CCIE R/S written book.) In my case, I was using non-XM 2610s, 12.3 Mainline, Enterprise Plus feature set.

Unfortunately, I should give a big lawyer disclaimer here. That's what I've seen in my lab. However, your results may vary, check with your product vendor, etc etc. The reason is that the Cisco feature navigator says that the 2600's don't support MPLS. Let me summarize what I did:

  • Open
  • Searched on "features"
  • Chose "MPLS (Multiprotocol Label Switching)"
  • The next page's "model" pull-down doesn't list 2600's.

Following that process, the pull down list does include 2650/2651 XM's, 1841/1861, and 3640, to name a few. But the rest of the 2600 (XM and non-XM) models are not listed, plus 2500's, 800's, and 1700's are missing as well. So, it's up to you to decide the risk of buying something that's difficult to confirm from the feature navigator. Of course, particularly for folks in the USA, it's not a lot ($50-$100 including shipping) to get a used 2610 and convince yourself by seeing it live and in person.

Next, to support MPLS VPN, you'll need a better router than the 2600 non-XM models.

I do know from experience that using a 2600 non-XM as an MPLS VPN PE router won't work. With MPLS VPNs, the Provider Edge (PE) routers do a lot of the control plane work (all the fun stuff with routing protocols and MPLS), with the Provider (P) routers in the middle of the MPLS network doing less control plane work, focusing instead of forwarding packets. Using feature navigator, listing just the MPLS VPN base feature, the same models are listed as for just "MPLS" - 2650/2651, 1841/1861, 3640, among others, but none of the usual cheaper routers.

So, what to do for MPLS labbing for CCNP today? I think there's a few main options:

  • To support just frame-mode, if you trust that 2610's will work, use them -they're cheap. (2 minimum, 3 is better).
  • To support just frame-mode, but you're reluctant to believe in the 2610's, the 3640 option is the most cost effective to support just frame-mode MPLS.
  • If you're betting you'll want to do MPLS VPN configuration, look at the 3640 as a good price performer today
  • If you can jus tread about MPLS, and not have to do hands-on labs, it's actually a small configuration topic - so, you could just ignore it for lab work.

So, what have you folks seen? Any other models where you see MPLS working where it's not listed in the feature navigator? Other thoughts?

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