[dpdk-dev] [PATCH 2/3] docs:tun/tap PMD information

[Wiles, Keith]

self Nak - just noticed the copyright notices are wrong. 

Regards,
Keith

> On Sep 15, 2016, at 9:10 AM, Keith Wiles <keith.wiles at intel.com> wrote:
> 
> Signed-off-by: Keith Wiles <keith.wiles at intel.com>
> ---
> doc/guides/nics/tap.rst | 84 +++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 84 insertions(+)
> create mode 100644 doc/guides/nics/tap.rst
> 
> diff --git a/doc/guides/nics/tap.rst b/doc/guides/nics/tap.rst
> new file mode 100644
> index 0000000..072def8
> --- /dev/null
> +++ b/doc/guides/nics/tap.rst
> @@ -0,0 +1,84 @@
> +..  BSD LICENSE
> +    Copyright(c) 2016 Intel Corporation. All rights reserved.
> +    All rights reserved.
> +
> +    Redistribution and use in source and binary forms, with or without
> +    modification, are permitted provided that the following conditions
> +    are met:
> +
> +    * Redistributions of source code must retain the above copyright
> +    notice, this list of conditions and the following disclaimer.
> +    * Redistributions in binary form must reproduce the above copyright
> +    notice, this list of conditions and the following disclaimer in
> +    the documentation and/or other materials provided with the
> +    distribution.
> +    * Neither the name of Intel Corporation nor the names of its
> +    contributors may be used to endorse or promote products derived
> +    from this software without specific prior written permission.
> +
> +    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
> +    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
> +    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
> +    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
> +    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
> +    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
> +    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
> +    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
> +    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> +    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
> +    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> +
> +Tun/Tap Poll Mode Driver
> +========================================
> +
> +The rte_eth_tap.c PMD creates a device using TUN/TAP interfaces on the local
> +host. The PMD allows for DPDK and the host to communicate using a raw device
> +interface on the host and in the DPDK application.
> +
> +The device created is a TAP device, which sends/receives packet in a raw format
> +with a L2 header. The usage for a TAP PMD is for connectivity to the local host
> +using a TAP interface. When the TAP PMD is initialized it will create a number
> +of tap devices in the host accessed via 'ifconfig -a' or 'ip' command. The
> +commands can be used to assign and query the virtual like device.
> +
> +These TAP interfaces can be used with wireshark or tcpdump or Pktgen-DPDK along
> +with being able to be used as a network connection to the DPDK application. The
> +method enable one or more interfaces is to use the --vdev=eth_tap option on the
> +DPDK application  command line. Each --vdev=eth_tap option give will create an
> +interface named dtap0, dtap1, ... and so forth.
> +
> +.. code-block:: console
> +
> +   The interfaced name can be changed by adding the iface=foo0
> +   e.g. --vedv=eth_tap,iface=foo0 --vdev=eth_tap,iface=foo1, ...
> +
> +.. code-block:: console
> +
> +   Also the speed of the interface can be changed from 10G to whatever number
> +   needed, but the interface does not enforce that speed.
> +   e.g. --vdev=eth_tap,iface=foo0,speed=25000
> +
> +After the DPDK application is started you can send and receive packets on the
> +interface using the standard rx_burst/tx_burst APIs in DPDK. From the host point
> +of view you can use any host tool like tcpdump, wireshark, ping, Pktgen and
> +others to communicate with the DPDK application. The DPDK application may not
> +understand network protocols like IPv4/6, UDP or TCP unless the application has
> +been written to understand these protocols.
> +
> +If you need the interface as a real network interface meaning running and has
> +a valid IP address then you can do this with the following commands:
> +
> +.. code-block:: console
> +
> +   sudo ip link set dtap0 up; sudo ip addr add 192.168.0.250/24 dev dtap0
> +   sudo ip link set dtap1 up; sudo ip addr add 192.168.1.250/24 dev dtap1
> +
> +Please change the IP addresses as you see fit.
> +
> +If routing is enabled on the host you can also communicate with the DPDK App
> +over the internet via a standard socket layer application as long as you account
> +for the protocol handing in the application.
> +
> +If you have a Network Stack in your DPDK application or something like it you
> +can utilize that stack to handle the network protocols. Plus you would be able
> +to address the interface using an IP address assigned to the internal interface.
> -- 
> 2.8.0.GIT
>