Issue 2: What if no prefix is advertised?

Issue: If stateful autoconfiguration is used, the routers
may not 
advertise any prefix in its RA message. DNA will not work
without prefix 
advertised. Current text relies on DHCP confirm message
exchange for DNA 
in that case.

Agreement at the meeting: Lets mandate the inclusion of one
prefix in 
all RA message, with L= 0 and A=0. But, atleast one prefix
is a MUST. 
The router MUST include the smallest prefix either in PIO or
LPO of all 
RA messages.
Note: I am not refering to the smallest prefix as
"LinkID" because in 
"Issue 6", I will be proposing the removal of the
concept of LinkIDs. 
The forward compatibility advantage of the LinkIDs can be
easily 
supported and refer to the email on Issue 6 is further
details.

If you have any objections to the proposed change please
post your 
objections on the list.

- Sathya

> Issue: If stateful autoconfiguration is used, the
routers may not
> advertise any prefix in its RA message. DNA will not
work without prefix
> advertised. Current text relies on DHCP confirm message
exchange for DNA
> in that case.
>
> Agreement at the meeting: Lets mandate the inclusion of
one prefix in
> all RA message, with L= 0 and A=0. But, atleast one
prefix is a MUST.
> The router MUST include the smallest prefix either in
PIO or LPO of all
> RA messages.
> Note: I am not refering to the smallest prefix as
"LinkID" because in
> "Issue 6", I will be proposing the removal of
the concept of LinkIDs.
> The forward compatibility advantage of the LinkIDs can
be easily
> supported and refer to the email on Issue 6 is further
details.
>
> If you have any objections to the proposed change
please post your
> objections on the list.

I agree and, IMO, the concept of 'LinkID' is of help. It
would be
simpler to mandate to include LinkID prefix.

Best Regards

JinHyeock

If we are going to mandate that the router advertise one
prefix even
when stateful autoconfiguration is used and that it must be
the smallest
prefix, we are implicitly requiring the adminstrator to
configure each
of these routers with this information, right? Or, are we
talking about
the routers sniffing DHCP messages - What does it mean?

I am leaving this open for now, until I hear comments on
this question.

- Sathya

JinHyeock Choi wrote:

>> Issue: If stateful autoconfiguration is used, the
routers may not
>> advertise any prefix in its RA message. DNA will
not work without prefix
>> advertised. Current text relies on DHCP confirm
message exchange for DNA
>> in that case.
>>
>> Agreement at the meeting: Lets mandate the
inclusion of one prefix in
>> all RA message, with L= 0 and A=0. But, atleast one
prefix is a MUST.
>> The router MUST include the smallest prefix either
in PIO or LPO of all
>> RA messages.
>> Note: I am not refering to the smallest prefix as
"LinkID" because in
>> "Issue 6", I will be proposing the
removal of the concept of LinkIDs.
>> The forward compatibility advantage of the LinkIDs
can be easily
>> supported and refer to the email on Issue 6 is
further details.
>>
>> If you have any objections to the proposed change
please post your
>> objections on the list.
>
>
> I agree and, IMO, the concept of 'LinkID' is of help.
It would be
> simpler to mandate to include LinkID prefix.
>
> Best Regards
>
> JinHyeock

Hello Greg -

I agree with what you have said.

But, the open issue is different: the case we are talking
about with 
this issue is when stateful address configuration is used on
a 
particular link. We agreed during the last meeting to
mandate the router 
on such a link to advertise atleast one prefix (the smallest
prefix) 
with A=0 and L=0, so that the hosts can still use the RS/RA
exchange to 
find out about network attachement. At the moment, there is
text in the 
draft for using DHCP CONFIRM - we thought we could remove
this text 
after mandating that routers advertise atleast one prefix.

My questions is: how will the routers know about a prefix if
stateful 
address configuration is used - do we understand/agree that
the routers 
MUST be configured with this information (atleast one
prefix) even when 
stateful address configuration is used. Is that acceptable?

Sathya

>Hi Sathya,
>
>We have an issue in that routers may already be
available which do
>not advertise a prefix (as it is not precluded).
>
>I would suggest that these routers should try to
advertise a prefix, 
>be it a learned or native (PIO) prefix.
>
>That way routers can participate if they learn of other
prefixes.
>Otherwise, they will still advertise if there are no
prefixes known anyway.
>This will provide hosts with the A= and M= flags
sufficient to initiate DHCP
>(which is not a DNA process but can provide the change
detection required).
>
>Greg
>
>----- Original Message -----
>From: Sathya Narayanan <sathyaresearch.panasonic.com>
>Date: Friday, January 19, 2007 8:10 am
>Subject: Re: [DNA] Issue 2: What if no prefix is
advertised?
>To: Dna <dnaeng.monash.edu.au>
>
>  
>
>>If we are going to mandate that the router advertise
one prefix even
>>when stateful autoconfiguration is used and that it
must be the 
>>smallestprefix, we are implicitly requiring the
adminstrator to 
>>configure each
>>of these routers with this information, right? Or,
are we talking 
>>aboutthe routers sniffing DHCP messages - What does
it mean?
>>
>>I am leaving this open for now, until I hear
comments on this 
>>question.
>>- Sathya
>>
>>JinHyeock Choi wrote:
>>
>>    
>>
>>>>Issue: If stateful autoconfiguration is
used, the routers may not
>>>>advertise any prefix in its RA message. DNA
will not work 
>>>>        
>>>>
>>without prefix
>>    
>>
>>>>advertised. Current text relies on DHCP
confirm message exchange 
>>>>        
>>>>
>>for DNA
>>    
>>
>>>>in that case.
>>>>
>>>>Agreement at the meeting: Lets mandate the
inclusion of one 
>>>>        
>>>>
>>prefix in
>>    
>>
>>>>all RA message, with L= 0 and A=0. But,
atleast one prefix is a 
>>>>        
>>>>
>>MUST.>> The router MUST include the smallest
prefix either in PIO 
>>or LPO of all
>>    
>>
>>>>RA messages.
>>>>Note: I am not refering to the smallest
prefix as "LinkID" 
>>>>        
>>>>
>>because in
>>    
>>
>>>>"Issue 6", I will be proposing the
removal of the concept of 
>>>>        
>>>>
>>LinkIDs.>> The forward compatibility advantage
of the LinkIDs can 
>>be easily
>>    
>>
>>>>supported and refer to the email on Issue 6
is further details.
>>>>
>>>>If you have any objections to the proposed
change please post your
>>>>objections on the list.
>>>>        
>>>>
>>>I agree and, IMO, the concept of 'LinkID' is of
help. It would be
>>>simpler to mandate to include LinkID prefix.
>>>
>>>Best Regards
>>>
>>>JinHyeock
>>>      
>>>
>>
>>    
>>

Hi Sathya,

I agree that we can ask DNA routers to do this,
and perhaps for DNA purposes MUST is OK.

Greg


----- Original Message -----
From: Sathya Narayanan <sathyaresearch.panasonic.com>
Date: Saturday, January 20, 2007 7:56 am
Subject: Re: [DNA] Issue 2: What if no prefix is
advertised?
To: Greg Daley <Greg.Daleyeng.monash.edu.au>
Cc: Dna <dnaeng.monash.edu.au>

> Hello Greg -
> 
> I agree with what you have said.
> 
> But, the open issue is different: the case we are
talking about 
> with 
> this issue is when stateful address configuration is
used on a 
> particular link. We agreed during the last meeting to
mandate the 
> router 
> on such a link to advertise atleast one prefix (the
smallest 
> prefix) 
> with A=0 and L=0, so that the hosts can still use the
RS/RA 
> exchange to 
> find out about network attachement. At the moment,
there is text in 
> the 
> draft for using DHCP CONFIRM - we thought we could
remove this text 
> after mandating that routers advertise atleast one
prefix.
> 
> My questions is: how will the routers know about a
prefix if 
> stateful 
> address configuration is used - do we understand/agree
that the 
> routers 
> MUST be configured with this information (atleast one
prefix) even 
> when 
> stateful address configuration is used. Is that
acceptable?
> 
> Sathya
> 
> >Hi Sathya,
> >
> >We have an issue in that routers may already be
available which do
> >not advertise a prefix (as it is not precluded).
> >
> >I would suggest that these routers should try to
advertise a 
> prefix, 
> >be it a learned or native (PIO) prefix.
> >
> >That way routers can participate if they learn of
other prefixes.
> >Otherwise, they will still advertise if there are
no prefixes 
> known anyway.
> >This will provide hosts with the A= and M= flags
sufficient to 
> initiate DHCP
> >(which is not a DNA process but can provide the
change detection 
> required).>
> >Greg
> >
> >----- Original Message -----
> >From: Sathya Narayanan <sathyaresearch.panasonic.com>
> >Date: Friday, January 19, 2007 8:10 am
> >Subject: Re: [DNA] Issue 2: What if no prefix is
advertised?
> >To: Dna <dnaeng.monash.edu.au>
> >
> >  
> >
> >>If we are going to mandate that the router
advertise one prefix even
> >>when stateful autoconfiguration is used and
that it must be the 
> >>smallestprefix, we are implicitly requiring the
adminstrator to 
> >>configure each
> >>of these routers with this information, right?
Or, are we talking 
> >>aboutthe routers sniffing DHCP messages - What
does it mean?
> >>
> >>I am leaving this open for now, until I hear
comments on this 
> >>question.
> >>- Sathya
> >>
> >>JinHyeock Choi wrote:
> >>
> >>    
> >>
> >>>>Issue: If stateful autoconfiguration is
used, the routers may not
> >>>>advertise any prefix in its RA message.
DNA will not work 
> >>>>        
> >>>>
> >>without prefix
> >>    
> >>
> >>>>advertised. Current text relies on DHCP
confirm message 
> exchange 
> >>>>        
> >>>>
> >>for DNA
> >>    
> >>
> >>>>in that case.
> >>>>
> >>>>Agreement at the meeting: Lets mandate
the inclusion of one 
> >>>>        
> >>>>
> >>prefix in
> >>    
> >>
> >>>>all RA message, with L= 0 and A=0. But,
atleast one prefix is a 
> >>>>        
> >>>>
> >>MUST.>> The router MUST include the
smallest prefix either in PIO 
> >>or LPO of all
> >>    
> >>
> >>>>RA messages.
> >>>>Note: I am not refering to the smallest
prefix as "LinkID" 
> >>>>        
> >>>>
> >>because in
> >>    
> >>
> >>>>"Issue 6", I will be
proposing the removal of the concept of 
> >>>>        
> >>>>
> >>LinkIDs.>> The forward compatibility
advantage of the LinkIDs can 
> >>be easily
> >>    
> >>
> >>>>supported and refer to the email on
Issue 6 is further details.
> >>>>
> >>>>If you have any objections to the
proposed change please post your
> >>>>objections on the list.
> >>>>        
> >>>>
> >>>I agree and, IMO, the concept of 'LinkID'
is of help. It would be
> >>>simpler to mandate to include LinkID
prefix.
> >>>
> >>>Best Regards
> >>>
> >>>JinHyeock
> >>>      
> >>>
> >>
> >>    
> >>
> 
>