Comments in line...
- Ralph
At 04:09 PM 8/12/2004 +0530, Syam Madanapalli wrote:
Hi Greg,
----- Original Message ----- From: "Greg Daley" <[EMAIL PROTECTED]> To: "Syam Madanapalli" <[EMAIL PROTECTED]> Cc: "Pekka Savola" <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]>; "Soohong Daniel Park" <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]> Sent: Thursday, August 12, 2004 8:19 AM Subject: Re: comments on draft-daniel-ipv6-ra-mo-flags-00.txt
> Hi Syam, > > Syam Madanapalli wrote: > > ----- Original Message ----- > > From: "Pekka Savola" <[EMAIL PROTECTED]> > > To: "Syam Madanapalli" <[EMAIL PROTECTED]> > > Cc: <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]>; "Soohong Daniel Park" > > <[EMAIL PROTECTED]> > > Sent: Wednesday, August 11, 2004 2:20 AM > > Subject: Re: comments on draft-daniel-ipv6-ra-mo-flags-00.txt > > > > > > > >>On Tue, 10 Aug 2004, Syam Madanapalli wrote: > >> > >>>M/O flags indicate the avaialbility of the respective service, so if > >>>a router advertises the M/O flags bits ON, I think we should OFF > >>>them if and only if the same router advertises again to OFF. It is > >>>administartor problem if one advertises with bits ON, and other > >>>router with bits OFF. > >> > >>How do you propose the host keeps track of which router advertised > >>which bits? This kind of tracking is not done at the moment. > > > > > > True, this requires one needs maintain the M/O flags information per router > > basis. And this leads to implementation complexity. But I think this method > > provides robust implemention. I am not sure how people are managing if > > two different routers on same link advertises two different Link MTU. I > > think the problem could be similar in both the cases. > > > Indeed it is similar. > > When you have trusted routers with differing configurations, > you have to make a decision what configuration to undertake. > > For MTU, it's clear that you need to take the smallest > (most restrictive) value advertised. This is because > choice of a higher MTU is likely to have worse effects > than
Yep, I agree. Using the smaller MTU one will be more safer. But it may be efficient to use the advertised MTU when the packet is destined for that particualr router because these two routers might have connected to different networks and the these routers may support different MTUs based on their hardware capabilities.
And, in general, the cross-product of possible decision scenarios against possible advertised values (MTU, M/O flags, etc.) from routers is, I think, too large and not sufficiently well-defined to be enumerated in the protocol specification. Guidance to implementors is a good thing, but it seems unlikely that we can correctly specify the required behavior for all hosts in all cases.
> For DHC it's not the same choice, although it requires similar > decision path. In DHC, any M or O flag set indicates that > there is a DHC server available (albeit it may provide > only limited function). > > In this case, the host can use a DHC server if any of the trusted > routers advertises this capability. In this case, > the scenario is least restrictive, rather than most restrictive. > > Certainly the routers should advertise consistent values, > but the hosts should make reasonable decisions even if > the routers disagree.
So you agree to maintain M/O flags per router basis and R1:M | R2:M|...|Rn:M = 1 means DHCPv6 Server available on the network? Similarly for O flag.
I agree.
> > Greg > >
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