NAME

        initPMTU - Verify that the NUT initialize Path MTU

TARGET

        Host

SYNOPSIS

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

NETWORK CONFIGURATION

        This test is OFF-LINK Network Configuration test.
        In this test, TN play a Roll of the Router.
        
        Phisical Network configuration
        
        ---------------------------------------
                |               |
                NUT             TN

        Logical Network Configuration

                                HOST A (globaladdress:A)
                                |
        ----------------------------------
                        |
                        Router
                        |
        ----------------------------------
                | 
                NUT (globaladdress:B)

        NUT < --- Router --- > HOST A

        In this configuration, Packets are send and received.

        for example,
                In Logical
                        HOST A           -- Echo Reply --> NUT
                Actually, in physical
                        TN (as Router X) -- Echo Reply --> NUT

INITIALIZATION

        There are 2 patterns for initialize.

        -- Test for host --

        The TN send a RA to assign global address prefix.

        TN              NUT

        -------------------

        ===multicast RA===>
        src=TN's link-local
        dst=LinkLocal-all-node                                                  
        M=0, O=0,
        Lifetime=3600, ReachableTime=60000, RetransTImer=1005
        Prefix:
           L=1, A=1,                       
           ValidLifetime=3600005, PreferredLifetime=3600005
           Prefix=3ffe:501:ffff:100::, PrefixLength=64                      
   
          Wait (5 sec.)
                 Ignoring DAD packets for global address.

        -- Test for router --

        TN attempt to execute remote command 'vRemote(route.rmt)'.
        
        'route add -inet6 3ffe:501:ffff:109 TN'slink-local-address'

TEST PROCEDURE

        "initPMTU" verifies that the node sets Path MTU of a path
         to the MTU of the first hop in the path.

        TN                      NUT

        ---------------------------

        1.
        After NUT is initialized ( reboot e.t.c) , NUT sets 
        the Path MTU of a path to 1500 of Ether's Link MTU.

        2.
        TN send Echo Request which is fragmented.

         === echo request 1st ===>

         === echo request 2nd ===>

        3.
        << JUDGMENT >>
        NUT send Echo Reply

         <=== echo reply ===

JUDGMENT

        << PASS >>
                NUT send Echo Reply which is no fragmented.
                
                NUT's Path MTU sets 1500 which is Ether Link MTU.

        << FAIL >>      
                NUT send Echo Reply which is fragmented.
                
                NUT can not initialize Path MTU of MTU.

                etc.