Re: Break Link and Remote Fault
[Date: 07/17/2000 From Seto]
Rich,
I guess I put a wrong button.
What I meant by 'not using IPG' was 'not mandating to send LSS signal once in
some SONET compatible period'. I have no problem with the idea, but I thought
many other did at the plenary. As Brad wrote, it is common in Ethernet to send
BL/LF signal during periods you don't anticipate MAC to send packets. I thought
many should not have a problem with such a method.
Seto
>
> Seto,
>
> As I see it, a transport for LSS which does not use Idle (in the absence of
> packets) or IPG (in the presence of packets) becomes an alternative link
> signaling protocol. Any such alternative link signaling protocol must still be
> robust and support the required functions of a link protocol. Depending on
> whether the link protocol must operate over a serial or parallel link, the
> following functions may be applicable: synchronization, deskew and clock
> tolerance compensation. LSS is defined atop the XAUI protocol, applicable to
> parallel links as well as 64B/66B, applicable to serial links.
>
> I have yet to see an alternative link signaling protocol proposed which meets
> all link protocol requirements as well as LSS does. Do you have anything
> specific in mind when you refer to an LSS protocol that doesn't use the IPG?
>
> A question back to you and the Task Force at large: If LSS information is
> terminated in the PHY and the MAC never knows about it, is anyone concerned
> about the fact that LSS, like XAUI and SUPI, alter the PHY representation of
the
> IPG?
>
> Best Regards,
> Rich
>
> --
>
> "Seto, Koichiro" wrote:
> >
> > [Date: 07/17/2000 From Seto]
> >
> > Shawn,
> >
> > I think using MAC frame means a big change to existing MAC, thus not a
> > good idea.
> >
> > LSS is a very solid link signaling proposal. I think we should start
> > >from LSS. The issue is whether we should use IPG or not.
> >
> > - 1000BASE-X uses Configuration order set (code set) to communicate Link
> > Failure, but not during IPG.
> > - 100BASE-FX uses special code sequence to communicate Remote Fault, but
> > not during IPG.
> >
> > I'd like to take a straw poll how many would support LSS if it does not
> > mandate to use IPG. ;-)
> >
> > Sincerely,
> > Seto
>
> -------------------------------------------------------
> Richard Taborek Sr. Phone: 408-845-6102
> Chief Technology Officer Cell: 408-832-3957
> nSerial Corporation Fax: 408-845-6114
> 2500-5 Augustine Dr. mailto:rtaborek@xxxxxxxxxxx
> Santa Clara, CA 95054 http://www.nSerial.com
>