Hi,all  I have got ecos running on our board using the CL_PS7500FE ARM processor. I have included  DM9008  ethernet chip and use the tcp/ip stack version 1_0b1 that I downloaded from the URL--sourceware.cygnus.com  .The chip really works.But when I ping the ecos with a packet more than 1500 bytes,the ecos never send the packet back.Why?Is there any bug in the tcp/ip stack?for when I debugged  the net device driver, I found the driver received the packet correctly .Anyone can help me?  thanks