[Rstplib-users] RE: 802.1w: double flushing in simplest case ?

[<al...@nb...>]

Ladies & Gentlemen !
Excuse me, routers & brouters are very interesting devices,
but what about my original question (double flushing in regular bridges) ?
Best regards, Alex

> -----Original Message-----
> From: own...@ma... 
> [mailto:own...@ma...]On Behalf Of Vipin Jain
> Sent: Thursday, January 03, 2002 7:11 PM
> To: Albina Krigma-Lee; Tony Jeffree
> Cc: std...@ie...; rst...@li...
> Subject: RE: 802.1w: double flushing in simplest case ?
> 
> 
> 
> Albina,
> 
> RSTP or bridging does not interfere with routing function. I suspect
> that you are talking about a bridge-router (brouter as it used to be
> called). RSTP is a no-op in a pure router.
> 
> In a brouter, you do not need to unresolve ARP entries or next hop
> information. Typically, you would have a number of bridged ports (part
> of the same layer 2 domain) and an IP interface (virtualized) 
> sitting on
> top of each such set of ports. Next hop in a routing table 
> will point to
> this virtual IP interface as the outbound interface. ARP resolution is
> also above the bridging function and hence does not need to change
> irrespective of what happens to bridge ports in the domain. 
> All it means
> is that a packet will be submitted to an appropriate IP interface for
> forwarding, you also know the MAC address of next hop router, just do
> not know which physical (bridge) port the packet should go out of.
> Because addresses have been flushed on these bridge ports, 
> such a packet
> will be flooded in the corresponding layer 2 domain.
> 
> Of course, if you change the IP address to MAC address 
> association for a
> device, no bridging will help you. That's why you have mechanisms such
> as gratuitous ARP (all layer 3 functions).
> 
> Hope it helps.
> 
> Vipin
> 
> -----Original Message-----
> From: Albina Krigma-Lee [mailto:alb...@ya...]
> Sent: Thursday, January 03, 2002 7:23 AM
> To: Tony Jeffree
> Cc: std...@ie...; rst...@li...
> Subject: Re: 802.1w: double flushing in simplest case ?
> 
> 
> 
> I see, but it seems that learning entries
> flushing/ageing must unresolve ARP entries and
> NextHops in FIB. So I quess, the double
> flushing could be really expencive cost of RSTP.
> Or Alex isn't right ?
> Sincerely, Albina Krigma-Lee
> 
>  --- Tony Jeffree <to...@je...> wrote:
> > The RSTP standard defines the operation of RSTP
> > bridges - it has nothing to 
> > say on the subject of routers.
> > 
> > Regards,
> > Tony
> > 
> > At 00:05 04/01/2002 +1100, Albina Krigma-Lee wrote:
> > 
> > >Hi All,
> > >If RSTP operates in a router and makes flush()
> > >function, do it have to delete Forwarding
> > Information
> > >Base (FIB) entries too ?
> > >
> > >Thanks in advance, albina
> > >
> > >
> > >http://my.yahoo.com.au - My Yahoo!
> > >- It's My Yahoo! Get your own!
> > 
> >  
> 
> http://my.yahoo.com.au - My Yahoo!
> - It's My Yahoo! Get your own!
> 
>