Re: [DNA] Comment on draft-jinchoi-dna-goals-00

[Greg Daley <greg.daley@eng.monash.edu.au>]

JinHyeock Choi wrote:
> [omitted]
> 
>>>>>1) Link local scope of Router Address  
>>>>>So if it happens that two different router interfaces have the 
>>>>>same link-local address, a host can't detect that it has 
>>>>>moved from one interface to another by checking the router 
>>>>>address in Router Advertisement messages. 
>>>>
>>>>I don't think above case is a real model, why two different router
>>>>interfaces are used with the same MAC ? did you have any 
>>>>experience on that ?
>>>
>>>Link-local not link-layer. 
>>
>>Um... same link-local address is generated from same MAC if they 
>>make use of EUI-64 format described in 2462. I am not sure it is a 
>>problem for DNA. Seems like a network mis-configuration by
>>administrator...
>>Am I missing anything ? 
> 
> 
> The same link-local address doesn't imply the same link-layer address. 
> The inverse doesn't hold either.  Neither necessary nor sufficient condition 
> among them.  
> 
> A few people informed us that it's rather common practice to assign the 
> same link-local address to the multiple interfaces of a router. 
>  
> Alper commented on it and I've heard that, at MoonV6, Cisco had assigned 
> the same link-local scope address fe80::1 to all of its router interfaces. 

It may also be possible that different interfaces using the same
public key generate the same CGAs for link-local.

Greg