[rbridge] Consensus Check: Point to Point links

[Silvano Gai]

Joe, 

inline

> -----Original Message-----
> From: Joe Touch [mailto:touch at ISI.EDU]
> Sent: Friday, October 05, 2007 6:01 PM
> To: Silvano Gai
> Cc: Eastlake III Donald-LDE008; Radia Perlman; Rbridge at postel.org
> Subject: Re: [rbridge] Consensus Check: Point to Point links
> 
> 
> 
> Silvano Gai wrote:
> > Joe,
> >
> >> -----Original Message-----
> >> From: Joe Touch [mailto:touch at ISI.EDU]
> >> Sent: Friday, October 05, 2007 5:23 PM
> >> To: Silvano Gai
> >> Cc: Eastlake III Donald-LDE008; Radia Perlman; Rbridge at postel.org
> >> Subject: Re: [rbridge] Consensus Check: Point to Point links
> >>
> >>
> >>
> >> Silvano Gai wrote:
> >>> Joe,
> >>>
> >>> If there is a bridge in between two RBridges you need to have a
full
> >>> adjacency table.
> >>>
> >>> If the link is point to point, you can save the table.
> >> If the link is point to point, I still need to know what to send
over
> >> the link, so each side still needs adjacency information.
> >
> >
> > This is not correct; you need to do a lookup to find the port, that
is
> > it.
> > Otherwise you need to do a lookup to find the MAC address, rewrite
the
> > MAC address and then another lookup to find the port.
> 
> So what do I save again? Yes, on the rewriting and additional lookup.
> But space?
> 

At 100 Gb/s you can send 150 millions frame/s, i.e. you have 6 ns/frame.
Any operation you save it counts. Also the memory bandwidth saved in
retrieving the rewrite information may make the difference from being
able to use off chip memory (larger) or being forced to stay on chip
(smaller).

-- Silvano