Lets be clear, Blown Fibre has no connotation or anything to with human bodily functions or sexual congress.
People who have an electrical background may think that a failed fibre optic cable is known as “blown fibre” in the same way that a “blown fuse” indicates that an electrical circuit has failed. But that would be wrong.
Blown Fibre refers to a specific category of cabling system where an plastic sheath is buried in the ground (or run through sewer pipes or hung from poles…. whatever) which has no actual glass fibre installed. The outer tube contains many inner tubes cells that are able to have a fibre core installed at a later date. The fibre core is inserted at one end and air-blower connected and powered up. The fibre is then fed the fibre down the tube until it gets to the other end.
The air-blown fibre may transit several sleeves at certain interconnect points. Now also that blown fibre can be removed and replaced with new fibre optic core in the future.
Mostly used for telecommunications in long haul backbones so that the fibre can be upgraded without trenching new fibres since new fibre materials can drastically improve the performance and distance of the signal.
There has been some talk of using blown fibre in the Data Centre since the introduction of different fibre optic cabling types for Storage (using OM-1/2/3 type cabling) compared to Ethernet. But FCoE and the rise of iSCSI means that all fibre in the modern data centre will be Ethernet. Thus there will be very little requirement for blown fibre in the data centre.
Caveat: It’s not clear what PHY the 40Gb or 100GB Ethernet will use, but it probably won’t be compatible with the modal response of the current fibre optic today, and the use of blown fibre may well be a good option for data centres that have to change networking, but cannot afford to take the risk of recabling the data centre.