Re: Echo request and echo reply

From: Piotr Matusiak <pitt2k_at_gmail.com>
Date: Tue, 1 Nov 2011 15:20:53 +0100

It seems to be Google specific in this case as when I ping cisco.com it
replies with the same size :)

Regards,

--
Piotr Matusiak
CCIE #19860 (R&S, Security), CCSI #33705
Technical Instructor
website: www.MicronicsTraining.com <http://www.micronicstraining.com/>
blog: www.ccie1.com
If you can't explain it simply, you don't understand it well enough -
Albert Einstein
2011/11/1 Carlos G Mendioroz <tron_at_huapi.ba.ar>
> Hmm,
> The question was specific to 8.8.8.8, which is a specific host (or set of
> hosts :) that actually DO NOT behave like RFC-792 asks.
>
> FTR, RFC-792 says:
>
>  Data received in an ICMP Echo Request MUST be entirely included in the
>  resulting Echo Reply. However, if sending the Echo Reply requires
>  intentional fragmentation that is not implemented, the datagram MUST
>  be truncated to maximum transmission size (see Section 3.3.3) and
>  sent.
> ...
>
>  If a Record Route and/or Time Stamp option is received in an ICMP Echo
>  Request, this option (these options) SHOULD be updated to include the
>  current host and included in the IP header of the Echo Reply message,
>  without "truncation". Thus, the recorded route will be for the entire
>  round trip.
>
> but testing shows that 8.8.8.8 answers with small reply when data size
> gets over 64 bytes.
>
> -Carlos
>
> Piotr Matusiak @ 01/11/2011 10:00 -0300 dixit:
>
>> Yes
>>
>> Regards,
>> --
>> Piotr Matusiak
>> CCIE #19860 (R&S, Security), CCSI #33705
>> Technical Instructor
>> website: www.MicronicsTraining.com <http://www.micronicstraining.com/> <
>> http://www.micronicstraining.**com/ <http://www.micronicstraining.com/>>
>>
>> blog: www.ccie1.com
>>
>>  If you can't explain it simply, you don't understand it well enough  -
>> Albert Einstein
>>
>>
>> 2011/11/1 amin <amin_at_axizo.com>
>>
>> Hi experts,
>>>
>>>
>>>
>>> If I do extended ping 8.8.8.8 size 2000,  this is the size of the echo
>>> request, what will be the size of the echo replay? It will be the same
>>> size??
>>>
>>>
>>>
>>> Regards,
>>>
>>> Amin
>>>
>>>
>>> Blogs and organic groups at http://www.ccie.net
>>>
>>> ______________________________**______________________________**
>>> ___________
>>> Subscription information may be found at:
>>>
http://www.groupstudy.com/**list/CCIELab.html<http://www.groupstudy.com/list/
CCIELab.html>
>>>
>>
>>
>> Blogs and organic groups at http://www.ccie.net
>>
>> ______________________________**______________________________**
>> ___________
>> Subscription information may be found at: http://www.groupstudy.com/**
>> list/CCIELab.html <http://www.groupstudy.com/list/CCIELab.html>
>>
>>
>>
>>
>>
>>
>>
>>
> --
> Carlos G Mendioroz  <tron_at_huapi.ba.ar>  LW7 EQI  Argentina
Blogs and organic groups at http://www.ccie.net
Received on Tue Nov 01 2011 - 15:20:53 ART

This archive was generated by hypermail 2.2.0 : Thu Dec 01 2011 - 06:29:31 ART