NAME

        rfc2765_4.1_payloadlength.seq - Verify IPv6 <-> IPv4 header 
        translation in accordance with RFC2765 [SIIT]


TARGET

        Router


SYNOPSIS

        rfc2765_4.1_payloadlength.seq [-tooloption ...] 
        -p rfc2765_4.1_payloadlength.def


INITIALIZATION

	Before this test starts, run initialize.seq.


TEST PROCEDURE

        This test verifies that NUT can translates IPv4 header
        to IPv4 header, when IPv6 header contain options.
        
        Network Topology

        Link0
        --------------------------
            |               |
           TN              NUT
            |               |
        --------------------------
        Link1

        TN -- (Link0) -- NUT        NUT -- (Link1) -- TN
        
        ---------------------      ------------------------

        1.1.
        ===================>
        ICMPv6 Echo Request
                IPv6 Header
                        src address : TN LINK0 IPv4 embedded IPv6 address
                        dst address : TN LINK1 IPv4 embedded IPv6 address
                Destination options header
                ICMPv6 echo request
         
        1.2.
        <<JUDGMENT>>
                                   ===================>
        ICMPv4 Echo request
                IPv4 Header
                        src address : TN LINK0 IPv4 address
                        dst address : TN LINK1 IPv4 address
                        Don't Fragment = 1
                        MF = 0
                        FragmentOffset = 0
                        TotalLength = 34
                        Identifier = 0
                ICMPv4 echo request


JUDGMENT

        << PASS >>
                TN (Link1) an ICMPv4 Echo request.
                with correct total length.
                
        << FAIL >>      
                TN (Link1) receive an ICMPv4 echo requests, 
                with payload length 8 bytes too large.


NOTE


REFERENCE

RFC2765

4.1. Translating IPv6 Headers into IPv4 Headers

   If there is no IPv6 Fragment header the IPv4 header fields are set as
   follows:

         Total Length:
                 Payload length value from IPv6 header, plus the size
                 of the IPv4 header.

         Identification:
                 All zero.

         Flags:
                 The More Fragments flag is set to zero.  The Don't
                 Fragments flag is set to one.

         Fragment Offset:
                 All zero.


SEE ALSO

        perldoc V6evalTool