Find solution
Is Ethernet a protocol?

Which memory transfer technique is used by Ethernet protocol to write/read host memory?

  • I understand that Ethernet adapter can either user DMA or Programmed I/O to read/write host memory but which one is used. I am not able to find it.

  • Answer:

    Everyone uses DMA in one form or other. Also, designers go to great lenghts to avoid copying buffers in memory to improve performance. It makes a lot of difference for very high speed applications. There are a nice paper by Luca Deri, ntop's project leader, talking about this: http://luca.ntop.org/Ring.pdf.

Carlos Ribeiro at Quora Visit the source

Was this solution helpful to you?

Other answers

Network adapters haven't been driven by PIOs since the '80s.  Far too slow.

Tony Li

Even in the old days, when you could get something like a SEEQ8003 ethernet controller (10Mbps, parallel IO), connecting it to some sort of external DMA controller was about the only practical way to do packet IO.  Modern chips directly connect to modern buses (PCI, PCIE, etc.) I guess there are also some microcontroller-oriented ethernet chips (WizNet, Microchip ENC28J60) that have slow "programmed IO" interfaces, but that is usually achieved with dedicated buffer memory with DMA access to the actual physical ethernet.

Bill Westfield

Related Q & A:

Just Added Q & A:

Find solution

For every problem there is a solution! Proved by Solucija.

  • Got an issue and looking for advice?

  • Ask Solucija to search every corner of the Web for help.

  • Get workable solutions and helpful tips in a moment.

Just ask Solucija about an issue you face and immediately get a list of ready solutions, answers and tips from other Internet users. We always provide the most suitable and complete answer to your question at the top, along with a few good alternatives below.