[clug] multiple network ports on one machine
adrian.blake at ieee.org
Tue Mar 31 03:00:15 GMT 2009
A special purpose machine , a correlator, has 24 cards cramed packed
with fast Xilinx FPGAs. At the end of a 30 second period each card in
turn will dump the contents of its buffers onto the network. A total of
23, 721, 984 Kbps or per board (24 boards) = 988, 416 Kbps = 0.989
Gbps. With packetisation and other overheads this will exceed the
capacity of a single Gigabit port. Fortunately there are 4 Ethernet
ports per card, so I can use 2 at the same time. Via a network switch
this is feed into a computer(s) which has 4 gigabit Ethernet ports. So
there are two streams of data to be written to disk(s). Each port on the
FPGA card can address a specific destination Ethernet address on the
computer. The data will be sent as UDP packets. If I start 2 UDP servers
will each be associated with the different Ethernet address (physical
ports)? Is the solution to use different port numbers, i.e. bind IP
address x.x.x.y:aaaa and bind x.x.x.z:bbbb.
I know that the next bottleneck will be writing to disk, but I will
consider that later.
This data dumping occurs every 30 sec for 12 hours ..... lot of data.
> Adrian wrote:
>> To do some testing I wish to send UDP packets out on one Ethernet
>> interface, through a switch, and back in on another interface of a 4
>> port machine. What would be the basic server and client code to do this
>> or point me to some basic docs.
> I have never really consulted this book but numerous newsgroup and
> mailing lists point people to W. Richard Stevens' TCP/IP Illustrated
> book. The stuff you require might just be there.
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