MPLS explained

Sidebar: Steps to take: assess, RFP, implement

Step 1: Assess your network needs

Document the following:

1. Number of sites and bandwidth to each.

2. Devices and device configurations.

3. Your applications. How many applications do you have? What are they? How often are they used, and by whom?

4. Application characteristics. Describe the network characteristics of your applications. Are they store-and-forward (i.e., latency insensitive)? Or interactive? How "chatty" are they? In typical usage scenarios, how much bandwidth do they consume? How does that vary by time of day/week/month/year?

5. Other networks. Be sure to include applications that may be on other networks -- particularly video and voice). You'll want to document your current and planned voice, video and conferencing use.

6. Future plans. Network capacity requirements may change dramatically when that new ERP application rolls into production in 2009. Be sure to include any upcoming application .

7. Document to the best of your abilities your current availability and service guarantees. You'll need them to craft meaningful SLAs with your providers downstream.

Step 2: The RFP

When developing the request for proposals, there are a few key issues that are specific to MPLS-based services, including:

-- Timing. How far in advance you should start this process depends on the number of sites, the number of geographies and your starting state. But any comprehensive RFP process should be started a minimum of six months before the desired circuit turn-up. Eight months is better. Very early MPLS adopters invested several years in discussions with their carriers, but that's no longer necessary.

-- Service and access types. As noted, there are many different "flavors" of MPLS-based services. From a user perspective, the biggest distinction lies in the access technologies: Are services provided over copper or optical connections? What about wireless options? Is the carrier delivering native Ethernet, IP, or legacy services such as frame relay and ATM? Can remote users be connected in via VPNs? Ask service providers to offer details of each service they propose, including the specs they're based on and the gear they're using.

-- Network-to-network interfaces (NNIs). As much as possible, try to keep your sites on a single carrier's network (with the possible exception of having multiple carriers link to critical sites for redundancy). Ask about your carriers' NNI strategies, because few providers will offer end-to-end SLAs to offnet sites. Ask providers if they have a "short list" of other providers with whom they've established effective NNIs. Have them describe the certification process for adding providers to this list, what service guarantees can be made, and how they're enforced, and how cross-NNI troubleshooting is handled. The more you know, the more effectively you can manage cross-carrier connections.

-- Also ask about (and budget for) ongoing monitoring. Your carrier will assure you that the provider will monitor 'everything you need.' Trust, but verify -- you'll want tools of your own to keep the carrier honest.

-- Assess your backup options -- in many cases, backup for frame networks is provided by the same ISDN network that doubles as a videoconferencing infrastructure. With MPLS, not only is your overall bandwidth increasing, but your ISDN network may be going away. Ask carriers to discuss backup options in detail.

--Make sure you ask for details about quality of service and service-level guarantees. Most providers try to brush you off on these details -- don't let them.