[Autoconf] Re: Some Thoughts on Problem Statement.

[Shubhranshu <[e-mail]>]

Prof. Mase,

Please see below:

On 11/24/07, mase <[e-mail]> wrote:
> Dear Shubranshu,
>
> I think that your text cleary describes the issues.

Thank you. (also I received some private e-mail expressing this ....:-) )

>My comments and
> questions are in line.
>
> Thanks,
> Kenichi
>
> At 01:26 07/11/24, Shubhranshu wrote:
> >All,
<snip>
> >The probability of address duplication is quite low if most of the
> >/128 bits are randomly generated and so a node may skip address
> >uniqueness test. However, address uniqueness detection / resolution is
> >a requirement when smaller prefixes are used and also in military &
> >other critical MANET application scenarios. The address uniqueness
> >detection / resolution should be done across the entire  network thus
> >requiring that the specific broadcast/multicast messages used for this
> >purpose be propagated "even to MANET Routers that are multi-hop away".
> >Currently there is no standard specification that addresses this
> >requirement.
>
> The above description only covers pre-service DAD issue. I think that
> we should also describe in-service issue here. Thai is merger of two
> isolated MANETs may bring address conflict and the method of
> detecting and resolving the address conflict is required.
>

Agree, we need to include them. Later paragraph describes network
merger and related issues.

>
> >3) Configuration of Host interface:
> >
<snip>
> >- Scenario where no DHCP server is available.
> >
> >By its very nature, MANET environment does not always assume
> >availability of any pre-configured server. Even in such scenarios a
> >MANET router needs to configure an unique prefix. Traditionally,
> >protocols such as RFC 2462 are used for address configuration of nodes
> >in stateless manner. However,  RFC 2462 defines address auto
> >configuration mechanisms for nodes (host and router) and as such it
> >does not provide any mechanism for allocating "unique prefix(es)" to
> >the routers. For example, in Figure 2 below, a MANET Router, say MR3,
> >may need to receive prefix(es) (which can be further subnetted and
> >used for address configuration of its attached host nodes) from the
> >MANET Boarder Router /Access Router. Currently no specification exists
> >that addresses this requirement.
>
> I think that MANET Border Router/Access Router is not available or
> meaningful in this scenario where no DHCP server is available
> (stand-alone MANET).

Right, need to replace with MR4.


>
>
> >                              -- MR1...MR3 ....MR5
> >                    /
> >                  /               .
> >                 /                 .
> >          MR4                   .
> >                  \
> >                     \
> >                       \ -- MR2 ...
> >
> >Fig 2. (same as Fig 2 in draft-ietf-autoconf-statement-02)
> >
> >
> >Mobile and wireless nature of MANET routers result in dynamic network
> >topology [MANET-Arch ID, RFC 2501] which has the property of changing
> >neighbor nodes. These MANET properties result in network partitioning
> >and merger of initially isolated networks. Normally, once an address
>
> In this paragraph, you use address. Is this ok? You discuss unique
> prefix issues above.
> Should "address" here be replaced with prefix?

Prefixes.

>
> >is allocated to a node, it continues using it and collaborating to
> >detect and resolve duplicates in case its address is allocated to any
> >other node. Since initially isolated MANETs had allocated  addresses
> >independent with each other, there remains probability of more than
> >one node using same address. Currently there is no specification that
> >solves problem of MANET "network merger detection" and duplicate
> >address detection/ resolution resulting due to two / more MANETs
> >merger.
> >
> >It is desirable that network partitioning is also detected such that
> >resources / prefixes that were allocated to the outgoing nodes could
> >be re-used. Currently there is no specification to solve the problem
> >of MANET  "network merger detection".
>
> This should be "network partitioning detection"
>

Typo. Thanks for catching them.

- Shubhranshu

>
>
>
>
>


_______________________________________________
Autoconf mailing list
[e-mail]
https://www1.ietf.org/mailman/listinfo/autoconf