Thanks Poitr! That finally made me understand the difference between the two
flavours of traceroute.

Br Jimmy


2010/6/11 Piotr Kaluzny <[email protected]>

> ICMP TTL Exceeded message is used in all versions of traceroute - this is
> to discover all the routers in the transit path. For Windows-based
> traceroute you have to account for ICMP Echo reply messages - this is the
> response to ICMP Echos sent.
>
> For Unix traceroute, UDP probes are sent, as I mentioned before. This means
> that if the port is closed, ICMP Port Unreachable message will be sent back
> to the source of the probe (UDP is connectionless). In this particular task,
> all ICMP unreachables messages (Type 3) were allowed in, because on the ASA
> there is no way to specify individual messages (Codes) for this Type (you
> can do it on routers, though).
>
> Short recap on this :
> Windows traceroute - Account for ICMP TTL Exceeded + ICMP Echo Replies
> Unix traceroute - Account for ICMP TTL Exceeded + ICMP Port Unreachable
>
> In this particular example you don't have to bother about  opening holes
> for UDP probes (33434-33464), because this is allowed by default as the
> traffic is coming from higher to lower interface security level.
>
> Regards,
> Piotr
>
>
>
>
> On Fri, Jun 11, 2010 at 10:48 AM, Jimmy Larsson <[email protected]>wrote:
>
>> Thats exactly my point. So why does DSG open for ICMP-traffic, not UDP?
>>
>> /Jimmy
>>
>>
>> 2010/6/11 Piotr Kaluzny <[email protected]>
>>
>>> Unix-based traceroute sends UDP probes (Port Unreachable is expected to
>>> be received from the end device), whereas Windows-based sends ICMP Echo
>>> Requests (expects Echo Replies from the end device).
>>>
>>> Regards,
>>> Piotr K
>>>
>>>
>>>
>>> On Fri, Jun 11, 2010 at 10:08 AM, Jimmy Larsson <[email protected]>wrote:
>>>
>>>> But then, whats the difference between unix and windows traceroute
>>>> according to port/protocol usage?
>>>>
>>>> http://en.wikipedia.org/wiki/Traceroute
>>>>
>>>> http://www.topbits.com/how-unix-and-windows-traceroutes-differ.html
>>>>
>>>> <http://www.topbits.com/how-unix-and-windows-traceroutes-differ.html>Br
>>>> Jimmy
>>>>
>>>>
>>>> 2010/6/11 Piotr Kaluzny <[email protected]>
>>>>
>>>> Jimmy,
>>>>>
>>>>> ICMP_OBJ group covers Unix traceroute. It uses ICMP Type 3 Code 3 (Port
>>>>> Unreachable) and ICMP Type 11 Code 0 (Time Exceeded; TTL exceeded in
>>>>> transit).
>>>>>
>>>>> Cheers,
>>>>> Piotr K
>>>>>
>>>>>
>>>>>  On Fri, Jun 11, 2010 at 8:36 AM, Jimmy Larsson 
>>>>> <[email protected]>wrote:
>>>>>
>>>>>>  Hi!
>>>>>>
>>>>>> In Lab 18 task 1.6 we should allow unix-style traceroute thru the ASA.
>>>>>> DSG opens icmp-traffic but as far as I know unix-style traceroute uses
>>>>>> udp-ports. What am I missing here?
>>>>>>
>>>>>>  Br Jimmy
>>>>>>
>>>>>>
>>>>>> --
>>>>>> -------
>>>>>> Jimmy Larsson
>>>>>> Ryavagen 173
>>>>>> s-26030 Vallakra
>>>>>> Sweden
>>>>>> http://blogg.kvistofta.nu
>>>>>> -------
>>>>>>
>>>>>> _______________________________________________
>>>>>> For more information regarding industry leading CCIE Lab training,
>>>>>> please visit www.ipexpert.com
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Piotr Kaluzny
>>>>> CCIE #25665 (Security), CCSP, CCNP
>>>>> Sr. Support Engineer - IPexpert, Inc.
>>>>> URL: http://www.IPexpert.com
>>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> -------
>>>> Jimmy Larsson
>>>> Ryavagen 173
>>>> s-26030 Vallakra
>>>> Sweden
>>>> http://blogg.kvistofta.nu
>>>> -------
>>>>
>>>
>>>
>>>
>>> --
>>> Piotr Kaluzny
>>> CCIE #25665 (Security), CCSP, CCNP
>>> Sr. Support Engineer - IPexpert, Inc.
>>> URL: http://www.IPexpert.com
>>>
>>
>>
>>
>> --
>> -------
>> Jimmy Larsson
>> Ryavagen 173
>> s-26030 Vallakra
>> Sweden
>> http://blogg.kvistofta.nu
>> -------
>>
>
>
>
> --
> Piotr Kaluzny
> CCIE #25665 (Security), CCSP, CCNP
> Sr. Support Engineer - IPexpert, Inc.
> URL: http://www.IPexpert.com
>



-- 
-------
Jimmy Larsson
Ryavagen 173
s-26030 Vallakra
Sweden
http://blogg.kvistofta.nu
-------
_______________________________________________
For more information regarding industry leading CCIE Lab training, please visit 
www.ipexpert.com

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