Cell Relay Archive

[Paul Koning <pkoning@xedia.com>]

ÀÓÀçȯ wrote:
> 
> Hi!
> I want to develop ATM NIC using CN8236.
> My ATM NIC must interface two 155Mbps port(optic fiber) and two
> 25Mbps(UTP 3).
> I saw the schematic which is obtain from Conexant korea agent.
> This schematic tells me that four 155M port(optic fiber) is connect to
> RS8254 and RS8254 is connected to CN8236 using UTOPIA2 ,16bit-data bus
> 22Mhz Operation
> I think that this means the CN8236 can process the data stream of
> 622Mbps. But  when I read the Data sheet of CN8236, the data book  say
> to me that CN8236 have only 155Mbps full deplex bandwidth. So I think
> that CN8236 can't process four 155Mbps port. But the schematic says
> other story.
> I am confused for CN8236 ability to process four 155Mbps.
> What is correct?

The Cn8236 is a 155 Mb/s device, just like its predecessors.
So what you describe won't work.  You could do multiple 
lower speed ports (for example four 25 Mb/s ports, or three
DS-3 ports).  But an OC-3 optical interface will consume
the entire capacity of that chip.

You might get in touch with the company to ask them about
their plans for a higher speed device.

	paul