OM ). ▁B LO OM ▁introduced ▁increased ▁through put ▁of ▁ 2 ▁G bit / s ▁instead ▁of ▁ 1 ▁G bit / s . ▁ ▁Bro cade ▁integrated ▁B LO OM ▁into ▁its ▁first ▁" p ure " ▁director , ▁the ▁Sil k W orm ▁ 1 2 0 0 0 , ▁in ▁April ▁ 2 0 0 2 . ▁ ▁The ▁director ▁offered ▁up ▁to ▁ 1 2 8 ▁ports ▁in ▁two ▁ 6 4 - port ▁pseudo - switch es ▁( dom ains ). ▁ ▁The ▁ 1 2 0 0 0 ▁represented ▁several ▁internal ▁architecture ▁and ▁technical ▁changes ▁besides ▁the ▁new ▁AS IC : ▁it ▁had ▁an ▁upgrad ed ▁control ▁processor ▁architecture ▁( Int el ▁i 9 6 0 ▁moved ▁to ▁Power PC ▁ 4 0 5 GP ), ▁changed ▁the ▁embedded ▁operating ▁system ▁( F OS ▁v 4 . 0 ▁migr ated ▁from ▁Wind ▁River ▁Systems ▁V x Work s ▁to ▁Mont a V ista ▁Linux ), ▁and ▁introduced ▁the ▁back plane ▁architecture ▁( h ier arch ical ▁P CI ▁bus es ▁with ▁replace able ▁bl ades ▁attached ▁to ▁a ▁back plane ). ▁ ▁The ▁Blo om ▁AS IC ▁also ▁introduced ▁a ▁notable ▁cap ability ▁of ▁frame - level ▁F ib re ▁Channel ▁tr unk ing , ▁which ▁provided ▁high ▁through put ▁with ▁load ▁bal ancing ▁across ▁multiple ▁c ables . ▁ ▁It ▁needed ▁to ▁be ▁implemented ▁in ▁the ▁AS IC ▁hardware ▁to ▁ensure ▁in - order ▁delivery ▁of ▁frames . ▁ ▁Also ▁hot ▁firm ware ▁upgrade ▁was