IBM IBM 9077, Get Connected

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IBM 9077 SP Switch Router: Get Connected to the SP Switch
Receive Controller
and ProcessorThis component recognizes the SP Switch segments and
assembles them into IP packets in the 16 MB buffer.
Up to 256 IP datagrams can be handled
simultaneously. When a complete IP packet has been
received, the Receive Controller sends the packet to
the FIFO (1) queue for transfer to the serial daughter
card.
Buffer (1)This component is segmented into 256 64 KB IP packet buffers. It
is used to reassemble IP packets before sending them
to the FIFO queue, as switch data segments may
arrive out of order and interleaved with segments
belonging to different IP packets.
FIFO (1)This component is used to transfer complete IP packets to the serial
daughter card and even the flow of data between the
SP and GRF crosspoint switch.
FIFO (2)This component receives IP packets from the serial daughter card
and transfers them to Buffer (2).
Buffer (2)This buffer is used to temporarily store the IP packet while its IP
address is examined and a proper SP Switch route is
set up to transfer the packet through the SP Switch.
Send Controller
and ProcessorThis component is notified when an IP packet is received in
the FIFO (2) queue and sets up a DMA transfer to
send the packet to Buffer (2). The Send Processor
looks up the IP address in the packet header and
determines the SP Switch route for the packet, before
notifying the Send Controller to send the packet to the
Send TBIC from Buffer (2).
Send TBICThis component receives data from Buffer (2) and sends it in SP
Switch data segments to the SP Switch.
2.3.7 Media Card Performance
The SP Switch Router adapter has the following performance characteristics:
• It is able to transfer up to 100 MB per second. The limiting factor is the
crosspoint switch connection bandwidth.