episode-38.xml

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  <title>Control and Management Plane for IO Modules</title>
  <guests>Fulvio Risso from Politecnico di Torino</guests>
  <description>
    <p>
      Fulvio Risso is an associate professor at Politecnico di Torino in Turin,
      Italy.  His research is in the area of high-speed (10+ Gbps) packet
      processing and especially in programmable networks.  This interview was
      prompted by Fulvio's presentation ``<a
      href="http://fulvio.frisso.net/files/17-IOVisorSummit-CtrlMgmtPlane.pdf">A
      Control and Management Plane for IO Modules</a>'' at the IO Visor Summit
      held on Feb. 27 in Mountain View (see Quentin Monnet's excellent <a
      href="https://qmonnet.github.io/whirl-offload/2017/03/03/iovisor-summit-summary/">summary</a>
      of the summit for more information).
    </p>

    <p>
      The episode begins with a few words about <a
      href="http://opennetworking.kr/projects/ossn/wiki/_">OSSN 2017</a>, the
      2nd International Workshop on Open-Source Software Networking, which
      Fulvio co-chairs.  The interview occurred long before the workshop, which
      took place in early July.  See also the <a
      href="http://sites.ieee.org/netsoft/workshops/">workshop schedule</a>.
    </p>

    <p>
      An IO Module, according to Fulvio, is a kind of marketing term for an
      eBPF program.  In turn, eBPF is an abstract, portable, safe virtual
      machine that Linux allows userspace programs to install into the kernel
      to monitor, augment, or control kernel behavior.  OVS Orbit has
      previously covered eBPF in <a href="#e4">episode 4</a> on Cilium, <a
      href="#e23">episode 23</a> on the IO Visor project, and other episodes.
    </p>

    <p>
      According to Fulvio, for NFV packet processing, IO Modules have three
      primary advantages over other approaches.  First, they cab directly
      injected into a kernel.  Second, potentially, IO Modules can be injected
      at different layers, for example in the main networking stack or in a
      networking driver.  Third, eBPF programs are more portable than native
      code, which can be an important advantage for heterogeneous telco
      environment.
    </p>

    <p>
      Fulvio gives an example of the use of IO Modules for implementing the
      functionality of a residential network gateway.  IO Modules implement
      DHCP, routing, NAT, deep packet inspection, etc.  The advantage of an IO
      Module architecture over the traditional home gateway design is
      modularity: the IO Module design can be easily changed and adapted to
      suit a new use case.
    </p>

    <p>
      The <a href="https://github.com/iovisor/iomodules">IO Modules</a>
      repository includes a controller named Hover that is the main method
      proposed for IO Module deployment and (re)configuration.  Northbound,
      Hover provides a high-level REST API that accepts IO Modules or C code
      that can be transformed into eBPF; southbound, it talks to the Linux
      kernel to enable and connect IO Modules.  In addition, it provides some
      helpers that allow IO Modules to handle points of eBPF programming that
      are currently tricky.
    </p>

    <p>
      There is a clear analogy between Open vSwitch/OpenFlow and IO
      Modules/Hover.  In both cases, there is a kernel-based fast path, that
      sometimes needs to consult a userspace-based slow path, which
      occasionally needs to consult a controller over the network.  Open
      vSwitch uses OpenFlow for communication with the controller; for Hover,
      the protocol is yet to be determined.  Fulvio is considering whether to
      use an existing controller such as ONOS.
    </p>

    <p>
      Ben and Fulvio discuss how to divide the implementation between fast path
      and slow path, with ARP as an example.
    </p>

    <p>
      Fulvio briefly discusses the performance of IO Modules, which is
      generally competitive with related technologies.  The goal, however, is
      not performance, but flexibility.
    </p>

    <p>
      In the future, Fulvio plans to dedicate resources to bringing IO Modules
      into the larger IO Visor community.  Fulvio is also concerned that the IO
      Visor community is tied too tightly to individual companies.  He hopes
      for the community to expand further into university and research
      environments.
    </p>

    <p class="attribution">
      OVS Orbit is produced by <a href="mailto:blp@ovn.org">Ben Pfaff</a>.  The
      intro music in this episode is <a
      href="http://dig.ccmixter.org/files/AlexBeroza/43098">Drive</a>,
      featuring cdk and DarrylJ, copyright 2013, 2016 by Alex.  The bumper
      music is <a href="http://dig.ccmixter.org/files/speck/42100">Yeah Ant</a>
      featuring Wired Ant and Javolenus, copyright 2013 by Speck.  The outro
      music is <a href="http://dig.ccmixter.org/files/Kirkoid/43005">Space
      Bazooka</a> featuring Doxen Zsigmond, copyright 2013 by Kirkoid.  All
      content is licensed under a Creative Commons <a
      href="http://creativecommons.org/licenses/by/3.0/">Attribution 3.0
      Unported (CC BY 3.0)</a> license.
    </p>
  </description>
  <pubDate>Sun, 09 Jul 2017 18:27:21 GMT</pubDate>
</item>