Programmable high performance data communication adapter for high speed packet transmission networks

Claim 1

A line adapter (401, 402) for a switching node (300) in a packet communication network (200) including: a programmable processing means (SSP) for receiving (138) and transmitting (137) data packets of fixed or variable length; memory means having a plurality of buffers (132,800) for storing said data packets and a separate area (131) for working storage; means for identifying said data packets in said buffers including; buffer pointers (B -- PTR) each identifying one of the said data packet buffers, said buffer pointers including a status field for indicating when the pointed to buffer contains the end of a packet (EOP) or the end of a segment (EOS), a free buffer list (FBL) and an associated free buffer list pointer (P -- FBL) for identifying said list, said list including indicia indicating buffers which are free and available for use in storing packets, buffer lists (B -- LIST) each including a plurality of buffer pointers (B -- PTR) each identifying a buffer in the memory in which packet data is stored, packet pointers (P -- PTR) for identifying a said buffer list (B -- LIST), at least one list of packet pointers (P -- LIST), and queue pointers (Q -- PTR) for identifying a said packet pointer list (P -- LIST); means responsive to the detection of the end of segment (EOS) status for correlating buffers of the same packet having buffer pointers (B-PTR) in different buffer lists (B-LIST), whereby buffer lists (B-LIST) can be of uniform size or smaller than needed to accommodate the largest packet; means (FIG. 15) for listing said identifying means in said working storage (131) in a single instruction; means (FIG. 14) for delisting said identifying means in said working storage in a single instruction; and, means responsive to the delisting of a buffer for modifying the indicia in the free buffer list (FBL) to indicate the availability of the buffer.

Claim 9

A method of handling data packets in a line adapter (401, 402) for a switching node (300) in a packet communication network (200) which includes a memory, a programmable processing means (SSP) for receiving (138) and transmitting (137) data packets of fixed or variable length, said method including the following steps: dividing said memory into a plurality of buffers (132,800) for storing said data packets and a separate area (131) for working storage; establishing pointers and lists in the working storage for identifying said data packets in said buffers including; buffer pointers (B -- PTR) each identifying one of the said data packet buffers, said buffer pointers including a status field for indicating when the pointed to buffer contains the end of a packet (EOP) or the end of a segment (EOS), a free buffer list (FBL) and an associated free buffer list pointer (P -- FBL) for identifying said list, said list including indicia indicating which buffers are free and available for use in storing packets, buffer lists (B -- LIST) each including a plurality of buffer pointers (B -- PTR) each identifying a buffer in the memory in which packet data is stored, packet pointers (P -- PTR) for identifying a said buffer list (B -- LIST), queue pointers (Q -- PTR) for identifying a said packet pointer list (P -- LIST); detecting the end of segment (EOS) status for correlating buffers of the same packet having buffer pointers (B-PTR) in different buffer lists (B-LIST), whereby buffer lists (B-HST) can be of uniform size or smaller than needed to accommodate the largest packet; listing said identifying means (FIG. 15) in said working storage (131) in a single instruction; delisting said identifying means (FIG. 14) in said working storage in a single instruction; and, modifying the indicia in the free buffer list (FBL) to indicate the availability of the buffer following the delisting of a buffer.

Claim 10

A method of handling data packets in a line adapter (401, 402) for a switching node (300) in a packet communication network (200) which includes a memory, a programmable processing means (SSP) for receiving (138) and transmitting (137) data packets of fixed or variable length, said method including the following steps: dividing said memory into a plurality of buffers (132,800) for storing said data packets and a separate area (131) for working storage; establishing pointers and lists in the working storage for identifying said data packets in said buffers including; buffer pointers (B -- PTR) each identifying one of the said data packet buffers, said buffer pointers including a status field for indicating when the pointed to buffer contains the end of a packet (EOP) or the end of a segment (EOS), a free buffer list (FBL) and an associated free buffer list pointer (P -- FBL) for identifying said list, said list including indicia indicating which buffers are free and available for use in storing packets, buffer lists (B -- LIST) each including a plurality of buffer pointers (B -- PTR) each identifying a buffer in the memory in which packet data is stored, packet pointers (P -- PTR) for identifying a said buffer list (B -- LIST), queue pointers (Q -- PTR) for identifying a said packet pointer list (P -- LIST); detecting the end of segment (EOS) status for correlating buffers of the same packet having buffer pointers (B-PTR) in different buffer lists (B-LIST), whereby buffer lists (B-HST) can be of uniform size or smaller than needed to accommodate the largest packet; listing said identifying means (FIG. 15) in said working storage (131) in a single instruction; delisting said identifying means (FIG. 14) in said working storage in a single instruction; and, modifying the indicia in the free buffer list (FBL) to indicate the availability of the buffer following the delisting of a buffer.