Wednesday, January 10, 2007

Eat more fiber

There are a lot of questions about all the different fiber panels on the new network. In general, there are three different types of panels in use:

Bulk panel to Level3
These panels terminate the bulk fiber between the Internet2 suite and the Level3 centralized fiber termination block, known as the OSX. This bulk cable is used to carry client signals between equipment in our suite and the tributary cards on the Infinera transport gear. In router locations we have 96-strands (48-pair) of fiber going in each direction out of the city. So, in a three-way router site, we have three 96 strand cables going to the Level3 OSX. At smaller Ciena-only sites, we have 48 strands (24 pair) going in each direction.

Each 96 or 48 strand bulk cable is terminated across 4 or 2 single RU ADC fiber panels. These panels terminate 24 strands of the cable into SC-connectors. The panels are divided into two sides, with the left side of the panel aiming fibers out the left side of the rack, and the right side aiming fibers out the right side of the rack. (This becomes important when determining fiber lengths.) There are two rows of 6 strands on each side of the FDP. Strands 1-12 are on the left side and 13-24 are on the right side. The ports are numbered from left to right, with 1-6 on the top of the left side and 7-12 on the bottom of the left side. Level3's standards are to use ports that are on top of each other, rather than sequential numbered ports that are side by side. Hence, their circuits will terminate on ports 1 and 7, 2 and 8, 3 and 9, and so on. The right side of the FDP is numbered similarly, with the first port being 13.

Multifunction Panel
These panels are very simplistic 1 or 2 RU panels that have modular-style connectors. In router sites where we're obtaining a Level3 High-Speed IP (HSIP) ethernet drop or a coaxial timing connection, we have modules to support that. The rest of the connectors are generally SC-style to terminate customer fibers that land in our suite. We've issued LOAs to customers to allow them to land fibers within our suite. No customer fiber is to connect directly into our gear, aside from those within our suites. The customer fiber should land in the MFP on the back of the panel in the designated ports. Internet2 is responsible for the fiber patch between the MFP and the various pieces of equipment within the suite.

Ciena Fiber Trays
The Ciena interfaces often require simplex fibers to be run out different sides of the card. It's acceptable to run simplex fibers within a particular rack, so at Ciena-only sites where the Bulk Panels to Level3 are within the same rack, it's an acceptable fiber run. For router sites where the bulk FDPs are often in another rack, we decided against running the more fragile and less-available simplex fibers through the overhead fiber infrastructure and are placing a 1RU fiber distribution tray on top of the Ciena. This tray converts the LC-style connectors on the Ciena to SC-style, so we can maintain stock of the more common duplex SC-SC fibers.

Miscellaneous FDPs
There are some additional panels that are used in some of the 3rd party sites that fall outside of the norm. They are:

  • NEWY32AOA - bulk FDP to Fiber Meet Me Room (FMMR) - 48 strands
  • CHIC710NLSD - bulk FDP to 710NLSD Fiber Meet Me Area
  • WASH - bulk FDP to MAX suite on the same floor - 72 strands