Patent ID: 7262962

Claim:
An electronic system, comprising: a front set of circuit boards; a rear set of circuit boards; and an electronic equipment assembly which includes: a shelf having a front section configured to support the front set of circuit boards and a rear section configured to support the rear set of circuit boards, a midplane disposed within the shelf between the front section and the rear section, the midplane being configured to directly connect to the front set of circuit boards and to the rear set of circuit boards, and a fan subsystem disposed within the shelf, the fan subsystem being configured to generate an air stream through the front and rear sections with air flow of the air stream being faster through the front section past the front set of circuit boards relative to the rear section past the rear set of circuit boards; wherein the front set of circuit boards includes multiple programmable line card interface modules configured to exchange optical signals with an external network; and wherein the rear set of circuit boards includes multiple line cards and multiple fabric cards configured to exchange optical signals with an internal network; and wherein the fan subsystem of the electronic equipment assembly includes: a first fan tray having a first frame configured to engage with the shelf and a first set of fans disposed in a coplanar manner within the first frame; and a second fan tray having a second frame configured to engage with the shelf and a second set of fans disposed in a coplanar manner within the second first frame, the first fan tray being configured to push air of the air stream toward the second fan tray, and the second fan tray being configured to pull the air from the first fan tray.