Re: Joel Jaeggli's Discuss on draft-ietf-6man-ext-transmit-04: (with DISCUSS and COMMENT)

[Benoit Claise <[e-mail]>]

FYI, there is a middlebox definition at 
http://tools.ietf.org/html/rfc3303#section-2.1

Regards, Benoit
> On Oct 8, 2013, at 12:45 PM, Brian E Carpenter <[e-mail]> wrote:
>
>> Joel,
>>
>> Would this help?
>>
>> OLD
>>    Today, packets are often forwarded not only by straightforward IP
>>    routers, but also by a variety of intermediate nodes, often referred
>>    to as middleboxes, such as firewalls, load balancers, or packet
>>    classifiers.
>>
>> NEW
>>    Today, IPv6 packets are often forwarded not only on the basis of their
>>    first 40 bytes by straightforward IP routing. Some routers, and a
>>    variety of intermediate nodes often referred to as middleboxes, such
>>    as firewalls, load balancers, or packet classifiers, inspect other
>>    parts of each packet.
>>
> I find that more palatable yeah.
>
>> (and possibly some changes for consistency later in the document)
>>
>>     Brian
>>
>>
>> On 09/10/2013 08:22, joel jaeggli wrote:
>>> On Oct 8, 2013, at 12:06 PM, Brian E Carpenter <[e-mail]> wrote:
>>>
>>>> On 08/10/2013 20:19, Joel Jaeggli wrote:
>>>> ...
>>>>> ----------------------------------------------------------------------
>>>>> DISCUSS:
>>>>> ----------------------------------------------------------------------
>>>>>
>>>>> This is a dicuss because I'd like to see if I'm in the rough in this.
>>>>>
>>>>> Devices generally considered to be IP routers in fact are able to or find
>>>>> it necessary to forward on the basis of headers other than the IP header
>>>>> e.g. the transport header. By the definition applied in the problem
>>>>> statement all ipv6 capable routers in the internet that  I'm aware are or
>>>>> are capable of being middleboxes.
>>>> IMHO, yes, if a box is taking a forwarding decision on the basis of anything
>>>> other than the first 40 bytes of an IPv6 header, then it's a middlebox
>>>> as far as this draft is concerned. Any such box is not a "straightforward IP
>>>> router".
>>>>
>>>> In the process of working on the draft I have actually corresponded briefly
>>>> with Steve Deering, and I'm pretty sure he would agree with me (with
>>>> added expletives).
>>> Right, so there are no IP routers on the internet today and you should update the document accordingly because as it stands now it seems to presume their existence.
>>>
>>>>> I would welcome the existence proof of an ipv6 capable router which is
>>>>> not capable of being a middlebox by the definition applied in the problem
>>>>> statement.
>>>>>
>>>>> I'm not sure that's a glaring flaw in the document but it certainly is
>>>>> with our vocabulary around taxonomy if true.
>>>>>
>>>>>
>>>>> ----------------------------------------------------------------------
>>>>> COMMENT:
>>>>> ----------------------------------------------------------------------
>>>>>
>>>>> If you need to find the transport header due to configured policy and you
>>>>> can't due to being unable to parse the extensions chain your configured
>>>>> action will be to drop. That perhaps weasels it's way through section 2.1
>>>>> requirements but it's still quite ugly.
>>>> Yes, and it's the reason that the Internet is mainly opaque to IPv6
>>>> extensions headers today.
>>>>
>>>>    Brian
>>>>