Jabber counter mechanism for elastic buffer operation

A computer network, comprising:

• a host system;
• at least one remote system;
• a multi-stage switch comprising a plurality of different switches which interconnect said host system via a host channel adapter to said remote system via a remote channel adapter along different physical links for data communications, and
• at least an elastic buffer provided in said host channel adapter of said host system for transferring data from a physical link into said host channel adapter which, said elastic buffer comprising:
• a memory storage coupled to receive link data from said physical link and to store said link data in a plurality of addressable memory locations;
• a write control mechanism which operates at a link clock for selecting as a write address the address of a memory location of said memory storage to store said link data, said write control mechanism comprising a Jabber counter which counts against a programmed time-out value to prevent a corresponding link data sequence from being stored in said memory storage so as to prohibit data overflow in said memory storage;
• and
• a read control mechanism which operates at a receiver clock for selecting as a read address the address of a memory location of said memory storage to retrieve said link data as receiver data, and for inserting No-Operation (NOP) sequences into said receiver data when said memory storage is determined empty so as to prohibit data underflow in said memory storage;
• wherein said write control mechanism further comprises:
• a write controller which operates at said link clock for prohibiting said IDLE signal included in said link data from being stored in said memory storage;
• and
• a write pointer which operates at said link clock for selecting as said write address the address of a memory location of said memory storage to store said link data therein.