NAME

        rfc2765_3.1_trafficclass.seq - Verify IPv6 <-> IPv4 header 
        translation in accordance with RFC2765 [SIIT]

TARGET

        Router

SYNOPSIS

        rfc2765_3.1_trafficclass.seq [-tooloption ...] 
        -p rfc2765_3.1_trafficclass.def

INITIALIZATION

	Before this test starts, run initialize.seq.

TEST PROCEDURE

        This test verifies that NUT translates IPv4 TOS 
        to IPv6 Traffic Class
        
        Network Topology

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

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

        1.[1-4]
                                   <===================
        ICMPv4 Echo request
                IPv4 Header
                        src address : TN LINK1 IPv4 address
                        dst address : TN LINK0 IPv4 address
                        Don't Fragment = 1
                        More fragments = 0
                        Offset = 0
                        TOS = 0,15,63,255 (4 tests)
                ICMPv4 echo request

        2.[1-4]
        <<JUDGMENT>>
        <===================
        ICMPv6 Echo Request
                IPv6 Header
                        src address : TN LINK1 IPv4 embedded IPv6 address
                        dst address : TN LINK0 IPv4 embedded IPv6 address
                        Traffic Class = 0,15,63,255 or 0,0,0,0
                ICMPv6 echo request
         
=head1 JUDGMENT

        << PASS >>
                TN (Link0) receive four ICMPv6 echo requests, 
                with Traffic class same as IPv4 TOS field.
                
        << WARN >>
                TN (Link0) receive four ICMPv6 echo requests, 
                with Traffic class = 0.
                
        << FAIL >>      
                TN (Link0) does not receive four ICMPv6 echo requests, 
                with Traffic class = 0 or same as IPv4 TOS field.

NOTE

REFERENCE

RFC2765

3.1. Translating IPv4 Headers into IPv6 Headers

         Traffic Class:
                 By default, copied from IP Type Of Service and
                 Precedence field (all 8 bits are copied).  According
                 to [DIFFSERV] the semantics of the bits are identical
                 in IPv4 and IPv6.  However, in some IPv4 environments
                 these fields might be used with the old semantics of
                 "Type Of Service and Precedence".  An implementation
                 of a translator SHOULD provide the ability to ignore
                 the IPv4 "TOS" and always set the IPv6 traffic class
                 to zero.