<varlistentry>
  <term>
    <emphasis remap='B'>ipsec-max-bytes</emphasis>
  </term>
  <listitem>
    <para>
      how many bytes can be sent, or how many bytes can be received on
      an IPsec SA instance for a connection; acceptable values are an
      integer optionally followed by

      <emphasis remap='B'>KiB</emphasis>,
      <emphasis remap='B'>MiB</emphasis>,
      <emphasis remap='B'>GiB</emphasis>,
      <emphasis remap='B'>TiB</emphasis>,
      <emphasis remap='B'>PiB</emphasis> or
      <emphasis remap='B'>EiB</emphasis>

      to signify kilobytes, megabytes, gigabytes, terabytes, petabytes
      or exabytes.

    </para>
    <para>
      An IPsec SA contains two keys, one for inbound and one for
      outbound traffic.  The
      <replaceable>ipsec-max-bytes</replaceable> sets two limits on
      each of these keys: the hard limit which is the total number of
      bytes that a given key can encrypt, and the soft limit which is
      the number of bytes that can be encrypted before a renegotiation
      of the IPsec SA is initiated.  Normally the renegotation (via
      the IKE SA) is completed before the
      <replaceable>ipsec-max-bytes</replaceable> value is reached.
    </para>
    <para>
      Pluto sets the the original initiator's soft limit to 25% of
      <replaceable>ipsec-max-bytes</replaceable> (with 12% fuzz) and
      on the original responder's soft limit to 50% of
      <replaceable>ipsec-max-bytes</replaceable> (with 12% fuzz).
      This way the original initiator hopefully is the one initiating
      the renegotiation of the IPsec SA.
    </para>
    <para>
      This option is not negotiated between IKE peers.  Each end of
      the IPsec SA sets their own limits independently.
    </para>
    <para>
      The default (hard limit) is 2^63 bytes.  The original
      initiator's soft limit is 2^61 bytes (approx.) and the original
      responder's soft limit is 2^62 bytes (approx.).
    </para>
  </listitem>
</varlistentry>
