pim_testsuite.tex

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\end{verbatim}


  \item In Part B, after TR1 is started, and after up to
        \verb=Triggered_Hello_Delay=
        ({\PimsmTriggeredHelloDelay}), the neighbor state information in the
        RUT must contain TR1:

\begin{verbatim}
Xorp> show pim neighbors 
Interface        DRpriority NeighborAddr     V Mode    Holdtime Timeout
dc1                       1 10.2.0.2         2 Sparse       105     103
\end{verbatim}

  \item In Part C, after TR1 is started, and after up to
        \verb=Triggered_Hello_Delay=
        ({\PimsmTriggeredHelloDelay}), the neighbor state information in the
        RUT must contain TR1 with protocol version of 15 (0xF).

\begin{verbatim}
Xorp> show pim neighbors 
Interface        DRpriority NeighborAddr     V Mode    Holdtime Timeout
dc2                       1 10.3.0.1        15 Sparse       105     103
\end{verbatim}

  \item In Part D, after TR1 is started and after it sends PIM messages
        containing a Type field of 0xF, the RUT should log the messages with
        this unrecognized Type field:

\begin{verbatim}
[ 2002/08/17 22:45:20 WARNING test_pim.rut PIM ] RX PIM_type_unknown from
10.3.0.2 to 224.0.0.13: message type (15) is unknown
\end{verbatim}

\end{itemize}

\para{Possible Problems:}
\begin{itemize}

  \item Earlier protocol specification (RFC 2117), have ``Addr length''
        field in place of the ``Reserved'' field. Therefore, the test in Part
        B may not be appropriate for such implementations.

  \item At the moment of writing, the lastest
        PIM-SM specification does not describe the behavior if a PIM message is
        received with protocol version that is larger than the implemented
        one.
        (TODO: if the specification later is modified to include that behavior,
        remove this bullet).
        Hence, in Part C, it is possible that an implementation may
        silently ignore all messages with protocol version larger than
        \verb=PIM_SM_version_default= ({\PimsmVersionDefault}).
        As a result, the RUT will not see TR1 as a neighbor.

  \item In Part D, the RUT may not log events such as receiving of a message
        with unrecognized Type field, because the logging is not described
        in the spec.

\end{itemize}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\newpage
\section{Holdtime Option}

\para{Purpose:}
Verify that a router properly sends and receives Hello messages with Holdtime
option.

\para{References:}
\begin{itemize}
  \item draft-ietf-pim-sm-v2-new-05 -- Sections 4.3.1 and 4.10.2
\end{itemize}

\para{Discussion:}
PIM capable routers periodically send Hello messages
messages to the ALL-PIM-ROUTERS address (224.0.0.13 for IPv4,
and ``ff02::d'' for IPv6). If a PIM router does not receive a Hello message
from a neighbor for some amount of time, it is assumed that the neighbor (or
the connectivity to it) is not operational, therefore the neighbor is
timed-out. A Hello message may contain a Holdtime option that specifies the
amount of time (in seconds) a router must keep the neighbor reachable.
If a Hello message does not contain a Holdtime option, the default value
of \verb=Default_Hello_Holdtime= ({\PimsmDefaultHelloHoldtime})
is assumed. If a Hello message contains a Holdtime option with value of
0xFFFF, then only one Hello message should be sent, and the router-recipient
of the message should not time-out the router-originator.

\para{Test Setup:}
Connect the RUT and TR1 according to Figure~\ref{fig:pim_test_2_4_holdtime_option}.
Enable PIM-SM on both the RUT and TR1.

\begin{figure}[htbp]
  \begin{center}
    \includegraphics[scale=0.8]{figs/pim_test_2_4_holdtime_option}
    \caption{Holdtime option test setup}
    \label{fig:pim_test_2_4_holdtime_option}
  \end{center}
\end{figure}

\para{Procedure:}

\subpara{Part A: Transmission of a PIM Hello message containing a Holdtime
option.}

\begin{enumerate}

  \item Start the RUT.

  \item Observe the messages transmitted by the RUT for at least
        \verb=Triggered_Hello_Delay= + 3 * \verb=Hello_Holdtime=
        (\ie ({\PimsmTriggeredHelloDelay}) + 3 * ({\PimsmHelloHoldtime})).

  \item Stop the RUT.

  \item Observe the messages transmitted by the RUT for at least
        \verb=Triggered_Hello_Delay= + 3 * \verb=Hello_Holdtime=
        (\ie ({\PimsmTriggeredHelloDelay}) + 3 * ({\PimsmHelloHoldtime})).

  \item Change the configuration value of \verb=Hello_Holdtime= and repeat.

\end{enumerate}

\subpara{Part B: Transmission of a PIM Hello message containing a Holdtime
option with value of 0xFFFF.}

The procedure is same as in Part A, except that the RUT is configured with
Holdtime option value of 0xFFFF. Note that the amount of time to observe the
transmitted messages should be same as in Part A.

\subpara{Part C: Reception of a PIM Hello message containing a Holdtime
option.}

\begin{enumerate}

  \item Start the RUT.

  \item Observe the neighbor state information in the RUT for at least
        \verb=Triggered_Hello_Delay= ({\PimsmTriggeredHelloDelay}).

  \item Configure TR1 such that its Hello messages would contain a Holdtime
        option with the default value of \verb=Hello_Holdtime=
        ({\PimsmHelloHoldtime}).

  \item Start TR1.

  \item Observe the neighbor state information in the RUT for at least
        \verb=Triggered_Hello_Delay= ({\PimsmTriggeredHelloDelay}).

  \item Stop TR1.

  \item Observe the neighbor state information in the RUT for at least
        \verb=Hello_Holdtime= ({\PimsmHelloHoldtime}).

  \item Change the configuration value of \verb=Hello_Holdtime= in TR1 and
        repeat.

\end{enumerate}

\subpara{Part D: Reception of a PIM Hello message containing a Holdtime option
with value of 0xFFFF.}

The procedure is same as in Part C, except that in Step 3 the Hello message
originated by TR1 must be configured contain a Holdtime option with value of
0xFFFF.

\subpara{Part E: Reception of a PIM Hello message that does not contain a
Holdtime option.}

The procedure is same as in Part C, except that in Step 3 the the Hello message
originated by TR1 must be configured to exclude the Holdtime option.

\para{Observable Results:}

\subpara{Part A:}

\begin{itemize}

  \item After the RUT is started, the first Hello message should be
        transmitted no later than \verb=Triggered_Hello_Delay=
        ({\PimsmTriggeredHelloDelay}).

  \item After the first Hello message, there should be one Hello message
        transmitted each \verb=Hello_Period= ({\PimsmHelloPeriod}). Each Hello
        message should contain a Holdtime option with default value of
        \verb=Hello_Holdtime= ({\PimsmHelloHoldtime}).

  \item Right after the RUT is stopped, there should be
        a Hello message transmitted with Holdtime option value of 0.

  \item After the Hello message with Holdtime option value of 0,
        no other Hello messages should be transmitted.

  \item The results of repeating the test with different value of
        \verb=Hello_Holdtime= should be similar, except that the
        Hello messages should be transmitted every 1/3th of
        the new \verb=Hello_Holdtime=, and the Holdtime Option value
        in the Hello messages should be the new \verb=Hello_Holdtime=.

\end{itemize}

\subpara{Part B:}

\begin{itemize}

  \item After the RUT is started, the first Hello message should be
        transmitted no later than \verb=Triggered_Hello_Delay=
        ({\PimsmTriggeredHelloDelay}). This message should contain
        a Holdtime option with value of 0xFFFF.

  \item After the first Hello message, there should be no one Hello messages
        transmitted before the RUT is stopped.

  \item Right after the RUT is stopped, there should be
        a Hello message transmitted with Holdtime option value of 0.

  \item After the Hello message with Holdtime option value of 0,
        no other Hello messages should be transmitted.

\end{itemize}

\subpara{Part C:}

\begin{itemize}

  \item Before TR1 is started, the neighbor state information in the RUT
  should show no PIM neighbors:

\begin{verbatim}
Xorp> show pim neighbors
Interface        DRpriority NeighborAddr    V Mode    Holdtime Timeout
\end{verbatim}

  \item After TR1 is started, and after up to \verb=Triggered_Hello_Delay=
        ({\PimsmTriggeredHelloDelay}), the neighbor state information in the
        RUT must contain TR1. The Holdtime information about TR1 must match
        the Holdtime value in the Hello messages by TR1:

\begin{verbatim}
Xorp> show pim neighbors
Interface        DRpriority NeighborAddr     V Mode    Holdtime Timeout
dc1                       1 10.2.0.2         2 Sparse       105     103
\end{verbatim}

  \item After TR1 is stopped, and after it sends a Hello message with Holdtime
        option value of 0, the RUT must immediately expire it.
        The neighbor state information in the RUT should show no PIM
        neighbors:

\begin{verbatim}
Xorp> show pim neighbors
Interface        DRpriority NeighborAddr     V Mode    Holdtime Timeout
\end{verbatim}

  \item The results of repeating the test with different value of
        \verb=Hello_Holdtime= should be similar, except that the
        Holdtime value in the state information in the RUT about TR1 should
        match the chosen value of the \verb=Hello_Holdtime=.

\end{itemize}

\subpara{Part D:}

The observed results should be same as in Part C, except that
after the first Hello message from TR1 is received, the neighbor state
information in the RUT must show that the TR1 would never be expired:

\begin{verbatim}
Xorp> show pim neighbors 
Interface        DRpriority NeighborAddr     V Mode    Holdtime Timeout
dc1                       1 10.3.0.2         2 Sparse     65535    None
\end{verbatim}

\subpara{Part E:}

The observed results should be same as in Part C, except that
the RUT assumes that the Holdtime value about TR1 is always equal to the
default value of \verb=Hello_Holdtime= ({\PimsmHelloHoldtime}).

\para{Possible Problems:}
None.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\newpage
\section{DR Priority Option}

\para{Purpose:}
Verify that a router properly sends and receives Hello messages with DR
Priority option.

\para{References:}
\begin{itemize}
  \item draft-ietf-pim-sm-v2-new-05 -- Sections 4.3.1, 4.3.2, and 4.10.2
\end{itemize}

\para{Discussion:}
One of the PIM routers on each LAN, the Designated Router (DR), needs to act
on behalf of the rest of the routers and directly connected hosts with respect
to the PIM protocol. The DR election considers the DR priority of each
PIM router and its IP address: numerically larger DR priority is always
better, with a numerically larger IP address used as a tie-break. Each PIM
router includes its DR priority in the DR Priority option of the Hello
messages it originates. If there is at least one PIM router on a LAN that does
not include the DR Priority option in its Hello messages, then the DR election
process considers only the IP addresses of the routers.

\para{Test Setup:}
Connect the RUT and TR1 according to Figure~\ref{fig:pim_test_2_5_dr_priority_option}.
Enable PIM-SM on both the RUT and TR1.

\begin{figure}[htbp]
  \begin{center}
    \includegraphics[scale=0.8]{figs/pim_test_2_5_dr_priority_option}
    \caption{DR priority option test setup}
    \label{fig:pim_test_2_5_dr_priority_option}
  \end{center}
\end{figure}

\para{Procedure:}

\subpara{Part A: The RUT has a numerically larger IP address than TR1.}

\begin{enumerate}

  \item Start the RUT with default DR priority of 1, and
        observe the DR state information in the RUT.

  \item Start TR1 with default DR priority of 1, and
        observe the DR state information in the RUT.

  \item Change the DR priority of TR1 to 2, and
        observe the DR state information in the RUT.

  \item Change the DR priority of TR1 to 0, and
        observe the DR state information in the RUT.

  \item Change the DR priority of TR1 to 1, and
        observe the DR state information in the RUT.

  \item Change the DR priority of the RUT to 2, and
        observe the DR state information in the RUT.

  \item Change the DR priority of the RUT to 0, and
        observe the DR state information in the RUT.

  \item Change the DR priority of the RUT to 1, and
        observe the DR state information in the RUT.

\end{enumerate}

\subpara{Part B: The RUT has a numerically smaller IP address than TR1.}

The procedure is same as in Part A, except that TR1 has a numerically smaller
IP address than TR1.

\para{Observable Results:}

\subpara{Part A:}

\begin{enumerate}

  \item After the RUT is started with default DR priority of 1, it should
        be the DR for LAN1:

\begin{verbatim}
Xorp> show pim interface dc2
Interface       State    Mode    V PIMstate  Priority DRaddr      Neighbors
dc2             UP       Sparse  2 DR               1 10.2.0.2            0
\end{verbatim}

  \item After TR1 is started with default DR priority of 1, the RUT should be
        still the DR for LAN1:

\begin{verbatim}
Xorp> show pim interface dc2
Interface       State    Mode    V PIMstate  Priority DRaddr      Neighbors
dc2             UP       Sparse  2 DR               1 10.2.0.2            1
\end{verbatim}

  \item After the DR priority of TR1 is increased to 2, TR1 should become the
  DR for LAN1. The DR state information in the RUT should show that the RUT is
  not the DR anymore: