Time_Exc_1.seq - Decrement Hop Limit to 0
Router
Time_Exc_1.seq [-tooloption ...] -p Time_Exc.def
Common Test Setup 1.1
Verify that a router properly generates Time Exceeded Messages the Hop Limit was exceeded in transit.
This test verifies that NUT sends valid ICMPv6 Time Exceeded (code 0)
in response to a packet which can not be forwarded.
And this test verifies that the message processing rule,
- If the message is a response to a message sent to one of the
node's unicast addresses, the Source Address of the reply must
be that same address.
- If the message is a response to a message sent to an address
that does not belong to the node, the Source Address should be
that unicast address belonging to the node that will be most
helpful in diagnosing the error. For example, if the message is
a response to a packet forwarding action that cannot complete
successfully, the Source Address should be a unicast address
belonging to the interface on which the packet forwarding
failed.
TN NUT
---------------------------
1.
=== echo request packet ===>
src address : TN global address
dst address : Off link host global address
hop limit : 1
2.
<< JUDGEMENT >>
<=== ICMPv6 Time Exceeded ===
src address : NUT global address
dst address : TN global address
Code is 0
<< PASS >>
The RUT must discard the ICMPv6 Echo Request from TN1.
Therefore, it must not forward the Echo Request.
The RUT should decrement the Hop Limit to 0 and
send a Time Exceeded Message to TN
with a code field valude of 0 (Hop Limit Exceeded in transit).
- The Source Address of the Packet should be one of the
RUT's unicast address used for packet forwarding.
- The Destination Address should be the same as TN's Source Address.
- The invoking Echo Request packet included in the Error Message must not exceed minimum IPv6 MTU.
Common Test Cleanup
RFC 4443 - ICMPv6 (ICMP for IPv6)
perldoc V6evalTool