The Free On-line Dictionary of Computing (30 December 2018):

Serial Storage Architecture

    (SSA) IBM's proposed ANSI standard for a standard
   high-speed interface to disk clusters and arrays.  SSA allows
   full-duplex packet multiplexed serial data transfers at
   rates of 20Mb/sec in each direction.

   According to John Taylor, programme manager at IBM's Storage
   Division at Havant, SSA will be used in arrays of discs
   working with high-end computers ranging from mainframes down
   to LAN servers.  Taylor said that SSA differs from the IEEE
   proposed P1394 serial interface specification in its ability
   to offer simultaneous multiplexed transfers from more than one
   disk or array.  IBM also supports the P1394 standard which
   will be used primarily by desktop PCs for multimedia
   applications.

   SSA has received backing from a number of companies including
   connector makers Molex, ITT Cannon and AMP, disk drive makers
   Conner and Western Digital and RAID array suppliers like
   Dynatech and NCR.  IBM expects to see the first SSA products
   released at Comdex in Autumn 1994 but it will be 1995 before
   the products ship in volume.

   Under an agreement signed with ASIC maker and ARM licencee
   VLSI Technology, IBM will use ARM-based chips made by VLSI
   to implement the SSA interface and VLSI will make these cores
   available to third parties as one of its Functional System
   Blocks.