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remote link status




Henry,

The remote link status is encoded in the IDLE stream in a PHY based on
the "10G-BASE-T" approach, which uses the Physical Coding Sublayer
(PCS) of the 1000BASE-T standard + 4-WDM with a baud rate of
1.25 Gbaud/sec in the fiber.

Essentially, the remote transmitter uses the IDLEs it transmits to inform
the partner about the status of its (remote) receiver. If the remote receiver
is unable to lock or the line is dead, the remote transmitter will send this
information embedded in the IDLE stream it transmits back to the local
partner.

Could this help to satisfy Roy's requirements ?

Jaime

Jaime E. Kardontchik
Micro Linear
San Jose, CA 95131
email:kardontchik.jaime@xxxxxxxxxxx


Henry Ngai wrote:

> Roy,
>
> Quite a while back there was some talk on remote link down information in
> 802.3. If we can work that into the 10G Ethernet PHY specification, would
> that satisfy your requirement? Since we don't use link pulse, may be we can
> put in something in the line coding scheme to indicate remote link status?
> The original remote link down function basically uses the link pulse to
> inform the MAC that the up link is failing. Even if ping fails because of
> failing optics on the up link, we can still get the link status on the up
> link from the other MAC. What do you think?
>
> Thanks!
> Henry Ngai
>
> ----- Original Message -----
> From: Roy Bynum <rabynum@xxxxxxxxxxx>
> To: <mick@xxxxxxxxxxx>
> Cc: <stds-802-3-hssg@xxxxxxxx>
> Sent: Monday, August 30, 1999 8:25 PM
> Subject: Re: Please help to clarify some things!
>
> >
> > Mick,
> >
> > The splice points are just physical joinings of the fiber.  The problem is
> that
> > they can be inconsistent to the point of effecting the functionality of
> the data
> > transmission.  They can also be effected by people messing with them in
> the
> > process of working on the fiber cable.   As a cable degrades or is damaged
> the
> > link level may fail to the point of not being able to use "ping", yet the
> remote
> > status information can inform you of whether the problem is in both
> directions
> > of the traffic, or just one, and which one.  A ping can not tell you if
> the link
> > failed in one direction only. As a transmission laser starts to fail, the
> remote
> > system returning its receive status information can cause an allert/trap
> against
> > the local system, even though the problem was seen on the remote system.
> At
> > present, SNMP can only tell you if there are excessive error frames.  It
> does
> > not have visibility at the optical level.  Having a network management
> system be
> > able to properly report where the problem is will save a lot of time,
> effort,
> > and expensive support people in the process of resolving the problem.
> Part of
> > what I am recommending is adding to SNMP the visibility to the optical
> level.
> >
> > Thank you,
> > Roy Bynum
> > MCI WorldCom
> >
> > Mick Seaman wrote:
> >
> > > Roy,
> > >
> > > I'm sorry, I feel you are repeating "full duplex 10Gb 802.3 is in need
> of
> > > protocol
> > > level operations support functionality" but not adding to my
> understanding
> > > of why at all. I am probably not alone.
> > >
> > > Can we be more specific about those things that the functionality you
> > > propose will enable us to diagnose that can not be accomplished by
> > > collecting data in the systems attached to the Gigabit MAC and then
> sharing
> > > that data or responding to queries using that MAC to transmit and
> receive.
> > >
> > > Is it possible to see or manage the splice points you refer to using an
> > > embedded protocol? I thought they were just physical splice points and
> that
> > > none of the protocols you were discussing contained embedded OTDR. So
> the
> > > only thing that would help me to manage these would be better insight
> into
> > > BER or 'physical' level signal conditioning at the end stations. Why
> can't I
> > > get at the information provided by this using SNMP, or check
> connectivity
> > > using 'ping' etc. etc. What is there here that needs support in the MAC?
> It
> > > may be that the world needs better management protocols but why is that
> a
> > > subject for HSSG discussion?
> > >
> > > Mick
> > >
> > > From: owner-stds-802-3-hssg@xxxxxxxxxxxxxxxxxx
> > > [mailto:owner-stds-802-3-hssg@xxxxxxxxxxxxxxxxxx]On Behalf Of Roy Bynum
> > > Sent: Sunday, August 29, 1999 10:24 PM
> > > To: Henry Ngai
> > > Cc: stds-802-3-hssg@xxxxxxxx
> > > Subject: Re: Please help to clarify some things!
> > >
> > > Henry,
> > >
> > > In your document, your first and second drawings are somewhat correct.
> I
> > > doubt
> > > that 10GbE would ever be implemented as you are showing it in your third
> > > drawing.  In your first drawing, you need to add a fiber plant that has
> > > things
> > > like splice points every 5 km at most, access to the fiber cable by
> people
> > > that
> > > have nothing to do with your data, and other issues.  The traditional
> 802.3
> > > LAN
> > > environment was outgrown when full duplex 802.3 over optical transport
> was
> > > standardized.  It is even possible to take full duplex 100BaseFX over
> WAN
> > > distances with optical converters that are sold by several different
> > > vendors.
> > > As seen by individuals that are attempting to create manageable
> enterprise
> > > level data networks with GbE, full duplex 10Gb 802.3 is in need of
> protocol
> > > level operations support functionality in order to grow to its true
> > > potential.
> >
> >