Thursday, April 12, 2007

So why hasn't the Washington DC router moved yet?

In a word: Atlanta.

Have a look at this image to the right, which depicts the current state of the network, with both the Qwest and Level3 backbone links. Note that the old Abilene network (with routers in blue) and the new Internet2 network (with routers in red) are interconnected in New York and Chicago. Those two links are keeping the two networks talking to each other.

If we were to remove the Washington DC router, we would also have to turn down the DC to New York Qwest OC-192, which would mean the two networks are only interconnected in Chicago. Unacceptable.

A few months back, we looked at two different options to keep the networks dual-homed. The first was to do something similar to what we did in Indianapolis: have Qwest patch the southern route into a single Houston to New York circuit. The second option was to figure out a way to create an interconnect in Atlanta. Because we didn't like the idea of traffic having to go all the way to New York to get between the two networks, we focused on interconnecting in Atlanta. Stay with me.

Atlanta has a few additional quirks that make t
he transition a bit more difficult. Ever since the 2002 migration to the Juniper platform, we've had a small Juniper M5 providing connectivity for the University of Mississippi OC-3 ATM (the T640 platform doesn't have small ATM interfaces). Mississippi isn't quite ready to move on our schedule yet, so we need to leave the M5 at the Qwest POP, with the Mississippi circuit still connected. So, we need to interconnect that M5 with the new T640 at Level3. There's a good 20 miles of space between the two POPs.

Fortunately, Georgia Tech is abandoning a pair of fiber between 56 Marietta and Forest Park (Qwest). Internet2 has two pair of metro fiber between 56 Marietta and 180 Peachtree (Level3). Georgia Tech's connection will migrate to the Internet2 metro fiber, thus freeing us up to use their old 20 mile run out to Qwest from 56M.

The original plan was to put the M5 GigE interconnect on one pair of fiber and SOX on the other pair. But then we realized that we could swing the Qwest Houston to Atlanta circuit up from the Qwest POP in Atlanta to the Level3 POP in Atlanta. That circuit passes near 56 Marietta, so we started down the path of figuring out how to cram three signals onto two pair of fiber. The solution was a wideband CWDM passive optical splitter. The SOX and M5 GigE will share a pair of fiber and the Qwest circuit will ride the other.

Even though I know that's crystal clear and no one could possibly be confused, I made up a somewhat irrelevant diagram to explain the obvious. :-)

Now that that is crystal clear, I'll explain the holdup. Raise your hand if you've ever had a fiber meet me room (FMMR) cross-connect work perfectly the first time around. I see five hands. When I discount those of you that are lying, I see one- and that person probably works in the FMMR. It's typical to encounter delays on getting panels right and making sure the person has the appropriate authorization to plug a fiber in. Each carrier wants it done a little differently. For example, Qwest wants the tech to dangle the fiber, but not plug it in. You need to open a ticket to have Qwest go out and plug the fiber in. None of this is particularly wrong- just difficult to navigate sometimes. That's what we're running into here.

We were hoping to do all the transition in Atlanta last night, but we've pushed it back to next week. That will delay the Washington DC router removal by a week. Since the DC router is being shipped to Kansas City, the KC install will likely also be pushed back. We have a bit of cushion on the schedule, so it's possible that things may accelerate past that, but probably unlikely.

So there you have it. I was clearly misinformed when I believed that Chicago was going to be the most complex transition in the network. That's looking like a campus wiring closet switch install compared to Atlanta. :-)