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What are the differences between a loopback driver & passthrough driver - NDIS 5.1 RRS feed

  • Question

  • Hello,

    I am a bit confused regarding the differences between a loopback driver & a passthrough driver. It would be helpful if you can clarify the idea.

    Thanks in advance & sorry for my English.


    fadedreamz
    Thursday, March 17, 2011 2:51 PM

Answers

  • The passthru driver does what it implies, it gets packets and without changing anything it passes the packets on to the NIC via NDIS.

    Not sure what you mean by "a loopback driver" but passthru can request the NIC to loopback packets on itself, i.e. a packet sent will be indicated on the receive path for that NIC. See NDIS_FLAGS_DONT_LOOPBACK and NDIS_MAC_OPTION_NO_LOOPBACK, I believe these are part of NDIS5.1.

    Larry C

    • Marked as answer by fadedreamz Thursday, March 17, 2011 6:02 PM
    Thursday, March 17, 2011 5:46 PM

All replies

  • The passthru driver does what it implies, it gets packets and without changing anything it passes the packets on to the NIC via NDIS.

    Not sure what you mean by "a loopback driver" but passthru can request the NIC to loopback packets on itself, i.e. a packet sent will be indicated on the receive path for that NIC. See NDIS_FLAGS_DONT_LOOPBACK and NDIS_MAC_OPTION_NO_LOOPBACK, I believe these are part of NDIS5.1.

    Larry C

    • Marked as answer by fadedreamz Thursday, March 17, 2011 6:02 PM
    Thursday, March 17, 2011 5:46 PM
  • Thanks Larry for your reply.

    "Not sure what you mean by "a loopback driver" but passthru can request the NIC to loopback packets on itself," - the loopback driver does this as per its name.

    Thanks again. I think I can differentiate between the passthrough and loopback drivers.

    Regards,

    Shovon.


    fadedreamz
    Thursday, March 17, 2011 6:02 PM