#!/usr/bin/perl
#
# Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005 Yokogawa Electric Corporation,
# IPA (Information-technology Promotion Agency, Japan).
# All rights reserved.
# 
# Redistribution and use of this software in source and binary forms, with 
# or without modification, are permitted provided that the following 
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# 
# 1. Redistributions of source code must retain the above copyright 
# notice, this list of conditions and the following disclaimer.
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# 2. 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.
# 
# 3. Neither the names of the copyrighters, the name of the project which 
# is related to this software (hereinafter referred to as "project") nor 
# the names of the contributors may be used to endorse or promote products 
# derived from this software without specific prior written permission.
# 
# 4. No merchantable use may be permitted without prior written 
# notification to the copyrighters. However, using this software for the 
# purpose of testing or evaluating any products including merchantable 
# products may be permitted without any notification to the copyrighters.
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# 
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHTERS, THE PROJECT AND 
# CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING 
# BUT NOT LIMITED THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
# FOR A PARTICULAR PURPOSE, ARE DISCLAIMED.  IN NO EVENT SHALL THE 
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# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 
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# THE POSSIBILITY OF SUCH DAMAGE.
#
# $TAHI: ct/nd/recvNsBasic.seq,v 1.34 2003/06/10 11:19:07 masaxmasa Exp $

########################################################################
BEGIN { $V6evalTool::TestVersion = '$Name: REL_2_1_2 $ '; }
 
use V6evalTool;
use nd;

ndOptions(@ARGV);

# The following generate debugging messages.
$nd::debug=$ndOpt_v|$ndOpt_vv;

# You can specifies debug options to a remote control program.
# If you want to know more detail, please see the following:
# - V6evalTool.pm: perldoc V6evalTool
# - V6evalRemote.pm: perldoc V6evalRemote
$nd::remote_debug="-o1" if $ndOpt_vv;

$IF=Link0;
$exit_rtn=$V6evalTool::exitPass;
$idx=0;

$wait_na=2;
$wait_reachable=$nd::REACHABLE_TIME * $nd::MAX_RANDOM_FACTOR + 1;
$wait_probe=$nd::DELAY_FIRST_PROBE_TIME + 1 +
    $nd::RETRANS_TIMER * $nd::MAX_UNICAST_SOLICIT + 1;


#
#
#
$type=$V6evalTool::NutDef{Type};
if($type ne router && $type ne host) {
    vLogHTML(ndErrmsg("ERROR: $V6evalTool::NutDef{Type}: ".
		      "Unknown target type<BR>"));
    exit $V6evalTool::exitFail;
}

#
# Start capture buffer.
#
vCapture($IF);

#
#
#
if($type eq router) {
    #
    # A target router should be pre-configured:
    # Link0: 3ffe:501:ffff:100 prefixlen 64
    #
} else {
    #
    # Send a RA (src:x's link, dst:allnode)
    # to advertise global prefix to the target.
    #
    $pktdesc{unsol_ra}=
	"Send unsolicited RA (link-local\@X ==> all-node mcast)";
    vSend($IF, unsol_ra);
}

#
#
#
$idx_snd=0;
$idx_scp=1;
$idx_exp=2;
$idx_msg=3;

#
@expects_ucast_ns_link2link_sll=
    (ucast_na_link2link_RSo, ucast_na_link2link_RSO_tll)
    if $type eq router;
@expects_ucast_ns_link2link_sll=
    (ucast_na_link2link_rSo, ucast_na_link2link_rSO_tll)
    if $type eq host;
@def_ucast_ns_link2link_sll=
    (
     ucast_ns_link2link_sll,
     'local',
     \@expects_ucast_ns_link2link_sll,
     'unicast NS w/ SLLA (link => link)',
     );

#
@expects_ucast_ns_link2global_sll=
    (ucast_na_global2link_RSo, ucast_na_global2link_RSO_tll)
    if $type eq router;
@expects_ucast_ns_link2global_sll=
    (ucast_na_global2link_rSo, ucast_na_global2link_rSO_tll)
    if $type eq host;
@def_ucast_ns_link2global_sll=
    (
     ucast_ns_link2global_sll,
     'local',
     \@expects_ucast_ns_link2global_sll,
     'unicast NS w/ SLLA (link => global)',
     );

#
@expects_ucast_ns_global2link_sll=
    (ucast_na_link2global_RSo, ucast_na_link2global_RSO_tll)
    if $type eq router;
@expects_ucast_ns_global2link_sll=
    (ucast_na_link2global_rSo, ucast_na_link2global_rSO_tll)
    if $type eq host;
@def_ucast_ns_global2link_sll=
    (
     ucast_ns_global2link_sll,
     'global',
     \@expects_ucast_ns_global2link_sll,
     'unicast NS w/ SLLA (global => link)',
     );

#
@expects_ucast_ns_global2global_sll=
    (ucast_na_global2global_RSo, ucast_na_global2global_RSO_tll)
    if $type eq router;
@expects_ucast_ns_global2global_sll=
    (ucast_na_global2global_rSo, ucast_na_global2global_rSO_tll)
    if $type eq host;
@def_ucast_ns_global2global_sll=
    (
     ucast_ns_global2global_sll,
     'global',
     \@expects_ucast_ns_global2global_sll,
     'unicast NS w/ SLLA (global => global)',
     );

#
@expects_mcast_ns_link2link_sll=
    (ucast_na_link2link_RSO_tll, ucast_na_global2link_RSO_tll)
#    (ucast_na_link2link_RSo, ucast_na_link2link_RSO_tll)
    if $type eq router;
@expects_mcast_ns_link2link_sll=
    (ucast_na_link2link_rSO_tll, ucast_na_global2link_rSO_tll)
#    (ucast_na_link2link_rSo, ucast_na_link2link_rSO_tll)
    if $type eq host;
@def_mcast_ns_link2link_sll=
    (
     mcast_ns_link2link_sll,
     'local',
     \@expects_mcast_ns_link2link_sll,
     'multicast NS w/ SLLA (link => solnode[link])',
     );

#
@expects_mcast_ns_link2global_sll=
    (ucast_na_global2link_RSO_tll)
#    (ucast_na_global2link_RSo, ucast_na_global2link_RSO_tll)
    if $type eq router;
@expects_mcast_ns_link2global_sll=
    (ucast_na_global2link_rSO_tll)
#    (ucast_na_global2link_rSo, ucast_na_global2link_rSO_tll)
    if $type eq host;
@def_mcast_ns_link2global_sll=
    (
     mcast_ns_link2global_sll,
     'local',
     \@expects_mcast_ns_link2global_sll,
     'multicast NS w/ SLLA (link => solnode[global])',
     );

#
@expects_mcast_ns_global2link_sll=
    (ucast_na_link2global_RSO_tll)
#    (ucast_na_link2global_RSo, ucast_na_link2global_RSO_tll)
    if $type eq router;
@expects_mcast_ns_global2link_sll=
    (ucast_na_link2global_rSO_tll)
#    (ucast_na_link2global_rSo, ucast_na_link2global_rSO_tll)
    if $type eq host;
@def_mcast_ns_global2link_sll=
    (
     mcast_ns_global2link_sll,
     'global',
     \@expects_mcast_ns_global2link_sll,
     'multicast NS w/ SLLA (global => solnode[link])',
     );

#
@expects_mcast_ns_global2global_sll=
    (ucast_na_global2global_RSO_tll, ucast_na_link2global_RSO_tll)
#    (ucast_na_global2global_RSo, ucast_na_global2global_RSO_tll)
    if $type eq router;
@expects_mcast_ns_global2global_sll=
    (ucast_na_global2global_rSO_tll, ucast_na_link2global_rSO_tll)
#    (ucast_na_global2global_rSo, ucast_na_global2global_rSO_tll)
    if $type eq host;
@def_mcast_ns_global2global_sll=
    (
     mcast_ns_global2global_sll,
     'global',
     \@expects_mcast_ns_global2global_sll,
     'multicast NS w/ SLLA (global => solnode[global])',
     );

#
#
#
@defs=
    (
     \@def_ucast_ns_link2link_sll,
     \@def_ucast_ns_link2global_sll,
     \@def_ucast_ns_global2link_sll,
     \@def_ucast_ns_global2global_sll,
     \@def_mcast_ns_link2link_sll,
     \@def_mcast_ns_link2global_sll,
     \@def_mcast_ns_global2link_sll,
     \@def_mcast_ns_global2global_sll,
     );

#
#
#
$idx=0;
foreach(@defs) {
    my($snd)=@$_[$idx_snd];
    my($scp)=@$_[$idx_scp];
    my($exp)=@$_[$idx_exp];
    my($msg)=@$_[$idx_msg];

    $title{$idx}="<TD>$msg</TD>";
    if(check($snd, $scp, $exp, $msg)) {
	$result{$idx}=$V6evalTool::exitPass;
	vLogHTML("<A NAME=\"T$idx\">OK</A><BR>");
    } else {
	$exit_rtn=$V6evalTool::exitFail;
	$result{$idx}=$exit_rtn;
	vLogHTML("<A NAME=\"T$idx\">".ndErrmsg("NG")."</A><BR>");
    }
    $idx++;
}

###############################################
# NS: link-local => link-local w/o SLLA
###############################################

#
# Clear buffer
#
$msg="unicast NS w/o SLLA (link => link)";
vLogHTML("<FONT SIZE=\"+2\">*** $msg ***</FONT><BR>");
$title{$idx}="<TD>$msg</TD>";

#
#
#
vLogHTML("<FONT SIZE=\"+1\">Initialization</FONT><BR>");
if(nd2NoNce($IF) != 0) {
    $exit_rtn=$V6evalTool::exitFail;
    $result{$idx}=$V6evalTool::exitFail;
} else {
    #
    #
    #
    vLogHTML("<FONT SIZE=\"+1\">Test</FONT><BR>");

    #
    # Send an unicast NS (src, tn's link, dst:link)
    #
    $pktdesc{ucast_ns_link2link}=
	"Send an unicast NS w/o SLLA (link-local\@TN ==> link-local\@NUT)";
    %ret2=vSend($IF, ucast_ns_link2link);

    #
    # Should capture multicast NS and solicited NA.
    #
    if($type eq router) {
	@expects = (mcast_ns_nut2tn_link2link,
		    ucast_na_link2link_RSo,
		    ucast_na_link2link_RSO_tll,
		    ucast_na_global2link_RSO_tll);
	$pktdesc{mcast_ns_nut2tn_link2link}=
	    'Got multicast NS (solnode[link-local]\@TN <== lin-local\@NUT)';
	$pktdesc{ucast_na_link2link_RSo}=
	    'Got an unicast NA (link-local\@TN <== link-local\@NUT)';
	$pktdesc{ucast_na_link2link_RSO_tll}=
	    'Got an unicast NA (link-local\@TN <== link-local\@NUT)';
	$pktdesc{ucast_na_global2link_RSO_tll}=
	    'Got an unicast NA (link-local\@TN <== global\@NUT)';
    } else {
	@expects = (mcast_ns_nut2tn_link2link,
		    ucast_na_link2link_rSo,
		    ucast_na_link2link_rSO_tll,
		    ucast_na_global2link_rSO_tll);
	$pktdesc{mcast_ns_nut2tn_link2link}=
	    'Got multicast NS (solnode[link-local]\@TN <== lin-local\@NUT)';
	$pktdesc{ucast_na_link2link_rSo}=
	    'Got an unicast NA (link-local\@TN <== link-local\@NUT)';
	$pktdesc{ucast_na_link2link_rSO_tll}=
	    'Got an unicast NA (link-local\@TN <== link-local\@NUT)';
	$pktdesc{ucast_na_global2link_rSO_tll}=
	    'Got an unicast NA (link-local\@TN <== global\@NUT)';
    }
    vLogHTML("Wait for NS/NA<BR>");
    while(1) {
	%ret=vRecv($IF, $wait_na, $ret2{sentTime1}, 1, @expects);
	if($ret{status} == 0) {
	    if($ret{recvFrame} eq mcast_ns_nut2tn_link2link) {
		#
		# Got a multicast NS (src:nut's link, dst:solnode[tn's link]).
		# So, send solicited NA (src:tn's link, dst:nut's link)
		#
		$pktdesc{ucast_na_tn2nut_link2link_rSO_tll}=
		    "Send NA (link-local\@TN ==> link-local\@NUT)";
		%ret2=vSend($IF, ucast_na_tn2nut_link2link_rSO_tll);
		next;
	    }
	    #
	    # Got solicited NA (src:tn's link, dst:nut's link).
	    # It is ok if the captured NA has a TLLA option or not.
	    # And that's it.
	    #
	    vLogHTML("<A NAME=\"T$idx\">OK</A><BR>");
	    $result{$idx}=$V6evalTool::exitPass;
	    last;
	} else {
	    vLogHTML("<A NAME=\"T$idx\">".
		     ndWarnmsg("WARN: Did not get an unicast NA ".
			       "(link-local\@TN <== link-local\@NUT)").
		     "</A><BR>");
	    $exit_rtn=$V6evalTool::exitWarn
		if $exit_rtn != $V6evalTool::exitFail;
	    $result{$idx}=$V6evalTool::exitWarn;
	    last;
	}
    }

    #
    # Skip all of solicited NAs.
    #
    readout($IF, $wait_probe);
}

#
#
#
vLogHTML("<FONT SIZE=\"+1\">Termination</FONT><BR>");
clear();

#
#
#
@col=('PTN');
ndPrintSummaryHTML("*** Test Summary: receiving NS vs sending NA ***", @col,
                   %title, %result, $idx);

vLogHTML("*** EOT ****<BR>");
exit $exit_rtn;

#
#
#
sub check($$\@$)
{
    my($snd)=@$_[$idx_snd];
    my($scp)=@$_[$idx_scp];
    my($exp)=@$_[$idx_exp];
    my($msg)=@$_[$idx_msg];

    #
    #
    #
    foreach(@$exp) {
	$pktdesc{$_}="Got NA: $_";
    }

    #
    #
    #
    vLogHTML("<FONT SIZE=\"+2\">*** $msg ***</FONT><BR>");

    #
    #
    #
    vLogHTML("<FONT SIZE=\"+1\">Initialization</FONT><BR>");
    if($scp eq global) {
	clearGlobal();
    } else {
	goto error if nd2NoNce($IF) != 0;
    }

    #
    # Send  NS (src:tn's link, dst:nut's link)
    #
    vLogHTML("<FONT SIZE=\"+1\">Test</FONT><BR>");
    $pktdesc{$snd}="Send NS: $snd";
    %ret=vSend($IF, $snd);

    vLogHTML("Wait for unicast NA<BR>");
    %ret=vRecv($IF, $wait_na, $ret{sentTime1}, 1, @$exp);
    goto error if $ret{status} != 0;

    #
    # Skip all of solicited NAs.
    #
    readout($IF, $wait_probe);

    return 1;

  error:
    vLogHTML(vErrmsg(%ret)."<BR>");
    return 0;
}

#
#
#
sub readout {
    # reading out NSs that NUT should send to TN
    my($if, $timeout) = @_;
    my(%ret)=vRecv($if, $timeout, 0, 0);
}

#
#
#
sub clear()
{
    return if $type eq router;
    $pktdesc{unsol_ra_clrrtr}="Clear the Default Router List";
    vSend($IF, unsol_ra_clrrtr);
}

#
#
#
sub clearGlobal()
{
    $pktdesc{echo_request_global2link}=
	'Send echo-request, then !NONCE';
    $pktdesc{na_global2link}=
	'Send NA, then REACHABLE';
    vSend($IF,
          echo_request_global2link,
          na_global2link,
          );

    vRecv($IF, $wait_reachable, 0, 0);
    vLogHTML("Then STALE<BR>");

    $pktdesc{echo_request_global2link}=
	'Send echo-request';
    vSend($IF,
          echo_request_global2link,
          );
    vLogHTML("Then DELAY->PROBE<BR>");
    vRecv($IF, $wait_probe, 0, 0);
    vLogHTML("Clear X's link-local<BR>");
}

########################################################################
__END__

=head1 NAME

recvNsBasic - Verifying that NUT acknowledges valid NSs

=head1 TARGET

Host and Router

=head1 SYNOPSIS

  recvNsBasic.seq [-tooloption ...] -p recvNsBasic.def

=head1 CASE I. A valid NS with SLLA

B<recvNsBasic> verify that NUT acknowledges B<a valid NS w/ SLLA>,
then returns a valid NA.

=head2 INITIALIZATION

=over 4

=item B<A CASE OF A HOST>

=begin html
<OL>
  <LI>Set a global prefix (3ffe:501:ffff:100::/64) with RA.
  <LI>Clear NC state for TN.
</OL>

=end html

  TN	               NUT
  ------------------------
  ==== unsolicited RA ===>
	src=X's link-local
	dst=NUT's link-local
	M=0, O=0
	LifeTime=600;
	ReachableTime=0;
	RetransTimer=0;
	Prefix Option:
		L=1, A=1
		ValidLifetime=2592000;
		PreferredLifetime=604800;

=item B<A CASE OF A ROUTER>

=begin html
<OL>
  <LI>NUT must be configured its interface under test (Link0)
      to have a global prefix of "3ffe:501:ffff:100::/64".
  <LI>Clear NC state for TN.
</OL>

=end html

=back

=head2 TEST PROCEDURE

=begin html
<PRE>
  TN	              NUT
  -----------------------
<BR>
  State: NONCE
<BR>
  ==== <A HREF="#JDG11">NS</A> ===>
	src=TN's link-local, global
	dst=NUT's link-local or global or 
            solicited-node[NUT's link-local] or
            solicited-node[global]
	w/ SLL
<BR>
  State: INCOMPLETE
<BR>
  <=== <A HREF="#JDG11">Judgment #1</A>: NA ====
	src=NUT's link-local or global
	dst=TN's link-local or global
	w/ or w/o TLL
</PRE>

=end html

=head2 JUDGMENT

=begin html
<PRE>
  <A NAME="JDG11">Input & output</A>
  ===============================+===================================
   NS (input)                    | NA (expected)
  -------+---------------+-------+-----------+------+-+-+-+----------
   Src   | Dst           | SLLA  | Src       | Dst  |<A HREF="#RFLAG">r</A>|<A HREF="#SFLAG">s</A>|<A HREF="#OFLAG">o</A>| <A HREF="#TLL">TLLA</A>
  =======+===============+=======+===========+======+=+=+=+==========
  link    link            exist  |link        link   * 1 0 none
                                 |link        link   * 1 1 exist
  -------+---------------+-------+-----------+------+-+-+-+----------
  link    global          exist  |link/global link   * 1 0 none
                                 |link/global link   * 1 1 exist
  -------+---------------+-------+-----------+------+-+-+-+----------
  global  link            exist  |link/global global * 1 0 none
                                 |link/global global * 1 1 exist
  -------+---------------+-------+-----------+------+-+-+-+----------
  global  global          exist  |global      global * 1 0 none
                                 |global      global * 1 1 exist
  =======+===============+=======+===========+======+=+=+=+==========
  link    sol-node[link]  exist  |link/global link   * 1 1 exist
  -------+---------------+-------+-----------+------+-+-+-+----------
  link    sol-node[global]exist  |link/global link   * 1 1 exist
  -------+---------------+-------+-----------+------+-+-+-+----------
  global  sol-node[link]  exist  |link/global global * 1 1 exist
  -------+---------------+-------+-----------+------+-+-+-+----------
  global  sol-node[global]exist  |link/global global * 1 1 exist
  =======+===============+=======+===========+======+=+=+=+==========
  *If NUT is a host, r-flag must be the zero.
  *If NUT is a router, r-flag is must be the one.
</PRE>

=end html

=head1 CASE II. A valid NS without SLLA

B<recvNsBasic> verify that NUT acknowledges B<a valid NS w/o SLLA>,
then returns a valid NA.

=head2 INITIALIZATION

  Clear NC state for TN.

=head2 TEST PROCEDURE

=begin html
<PRE>
  TN		                NUT
  ---------------------------------
<BR>
  State: NONCE
<BR>
  ==== <A HREF="#JDG21">unicast NS</A> ===>
	src=TN's link-local
	dst=NUT's link-local
	w/o SLL
<BR>
  State: INCOMPLETE
<BR>
  <=== <A HREF="#JDG22">Judgment #2</A>: multicast NS ====
	src=NUT's link-local or global
	dst=solicited-node[TN's link-local]
	w/ SLL
<BR>
  ==== solicited NA ===>
	src=TN's link-local
	dst=NUT's link-local
	R=0, S=1, O=1
	w/ TLL
<BR>
  State: REACHABLE
<BR>
  <=== <A HREF="#JDG23">Judgment #3</A>: solicited NA (if any) ====
	src=NUT's link-local or global
	dst=TN's link-local
	R=0/1, S=1, O=0
	w/ or w/o TLL
</PRE>

=end html

=head2 JUDGMENT

=begin html
<PRE>
<A NAME="JDG21"></A>
  1. Input and output
  ===============================+===================================
   NS (input)                    | NA (expected)
  -------+---------------+-------+-----------+------+-+-+-+----------
   Src   | Dst           | SLLA  | Src       | Dst  |<A HREF="#RFLAG">r</A>|<A HREF="#SFLAG">s</A>|<A HREF="#OFLAG">o</A>| <A HREF="#TLL">TLLA</A>
  =======+===============+=======+===========+======+=+=+=+==========
  link    link            none   |link/global link   * 1 0 none
                                 |link/global link   * 1 0 exist
  =======+===============+=======+===========+======+=+=+=+==========
  *If NUT is a host, r-flag must be the zero.
  *If NUT is a router, r-flag is must be the one.
<A NAME="JDG22"></A>
  2. <A HREF="#NOSLL">NUT may send at the least one multicast NS.</A>
     src=NUT's link-local, dst=solicited-node[TN's link-local], w/ SLL
<A NAME="JDG23"></A>
  3. NUT may send a solicited NA.
<BR>
     3.1. NUT is a host
          src=NUT's link-local, dst=TN's link-local,
          r=0, s=1, O=0, w/ or w/o TLL
<BR>
     3.2. NUT is a router
          src=NUT's link-local, dst=TN's link-local,
          r=1, s=1, O=0, w/ or w/o TLL
</PRE>

=end html

=head1 TERMINATION

  Send RA with RouterLifetime=0 to clear the Default Router List.

=head1 NOTE

=for html <A NAME="NODE1"></A>

  1. The command does not invoke any remote command.

=head1 REFERENCE

=begin html
<PRE>
RFC2461
<HR>
7.2.4.  Sending Solicited Neighbor Advertisements
<BR>
   A node sends a Neighbor Advertisement in response to a valid Neighbor
   Solicitation targeting one of the node's assigned addresses.  <B>The
   Target Address of the advertisement is copied from the Target Address
   of the solicitation.</B>  <A NAME="TLL"><B>If the solicitation's IP Destination Address is
   not a multicast address, the Target Link-Layer Address option MAY be
   omitted; the neighboring node's cached value must already be current
   in order for the solicitation to have been received.  If the
   solicitation's IP Destination Address is a multicast address, the
   Target Link-Layer option MUST be included in the advertisement.</B></A>
   Furthermore, <A NAME="RFLAG"><B>if the node is a router, it MUST set the Router flag to
   one; otherwise it MUST set the flag to zero.</B></A>
<BR>
   <A NAME="OFLAG"><B>If the Target Address is either an anycast address or a unicast
   address for which the node is providing proxy service, or the Target
   Link-Layer Address option is not included, the Override flag SHOULD
   be set to zero.  Otherwise, the Override flag SHOULD be set to one.</B></A>
   Proper setting of the Override flag ensures that nodes give
   preference to non-proxy advertisements, even when received after
   proxy advertisements, and also ensures that the first advertisement
   for an anycast address "wins".
<BR>
   <A NAME="SFLAG"><B>If the source of the solicitation is the unspecified address, the
   node MUST set the Solicited flag to zero and multicast the
   advertisement to the all-nodes address.  Otherwise, the node MUST set
   the Solicited flag to one and unicast the advertisement to the Source
   Address of the solicitation.</B></A>
<BR>
   If the Target Address is an anycast address the sender SHOULD delay
   sending a response for a random time between 0 and
   MAX_ANYCAST_DELAY_TIME seconds.
<BR>
   <A NAME="NOSLL"><B>Because unicast Neighbor Solicitations are not required to include a
   Source Link-Layer Address, it is possible that a node sending a
   solicited Neighbor Advertisement does not have a corresponding link-
   layer address for its neighbor in its Neighbor Cache.  In such
   situations, a node will first have to use Neighbor Discovery to
   determine the link-layer address of its neighbor (i.e, send out a
   multicast Neighbor Solicitation).</B></A>
</PRE>

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=head1 SEE ALSO

  perldoc V6evalTool
  perldoc V6evalRemote

=cut