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RE: Ethernet over WANs




>
> You mention three choices
>
> 1. 10GbE over SONET where a proprietary OAM is done at SONET layer
> 2. 10Gbe over wavelengths where a proprietary OAM is done out of
> band in the
> optical channel
> 3. Native 10Gbe which would require some sort of new OAM protocol
>
> I thought 2  and 3 are the same ie you send 10GbE directly over
> DWDM rings and
> then do optical switching etc., rather than electronic switching (as in
> SONET). Am I correct?

No. There are a couple of companies that offer transparent GbE over DWDM
network.  To the user the connection looks like a back to back connection of
their GbE switches and network management, OAM&P are done out of band
(usually by a carrier). Option 2 is much closer to option 1 than option 3.

Native GbE on either dark fiber or with CWDM assumes that that there is no
other out of band  network management or OAM&P.  This GbE swithes are now
very mych aware of the WAN connection and the swicthes themselves must
address issues such as fiber breaks, buffering, etc

Bill


That too me is the key advantage of going
> directly over
> fiber. You save the expenses and headaches of another layer (SONET).
>
> BTW, is this/any other group thinking about standardising OAM for native
> 10GbE?
>
> Thanks
> Rohit Mittal
> Engineering, Microlinear Corp.
>
>
> >
> >  There are a number of parameters than can be suitably
> monitored for native
> > GbE over DWDM networks.  The "old" notion of SONET OAM&P is rooted in
> > assumptions that were true in mid- and late-80s when the
> transmission world
> > was seen to be quite limited in bandwidth and most of it came from
> > aggregation of low rate (DS0/DS1) circuits.
> >
> >  These native GbE OAM&P measures may be proprietary but they
> offer true GbE
> > extensions, not 'virtual' ones mapped into another layer.  SONET-like
> > functions such as physical layer protection switching (if
> required) can be
> > triggered off the user-settable thresholds for performance over
> a link and
> > the faults can be isolated to the desired level (section).
> >
> >  Aggressive new carriers and 'IP-service providers' may adopt
> this approach
> > while the Bellcore/Telcordia encumbered ILEC/RBOC carriers may
> still want
> > their SONET capabilities.
> >
> > -rohit
> > rohit@xxxxxxxxxxxxxxxxxxx
> > www.opticalnetworks.com
> >
> > > -----Original Message-----
> > > From: Bill St. Arnaud [mailto:Bill.St.Arnaud@xxxxxxxxxx]
> > > Sent: Thursday, August 05, 1999 10:13 AM
> > > To: Rohit Mittal
> > > Cc: stds-802-3-hssg@xxxxxxxx
> > > Subject: RE: Ethernet over WANs
> > >
> > >
> > >
> > > Rohit:
> > >
> > > There may be a set of reserved bits for OAM&P, but currently
> > > all of the
> > > OAM&P systems offered by vendors are proprietary and not
> > > interoperable.
> > > However, I understand the ITU is working on developing an
> > > interoperable
> > > standard.  How long that will take to percolate through the market is
> > > anybody's guess.
> > >
> > > Native GbE is being considered for a number of reasons - low cost,
> > > familiarity to LAN network administrators, etc.  There are a number of
> > > number of different ways OAM&P can be implemented with native GbE.  I
> > > suspect you will see some announcements in the next couple of
> > > months from a
> > > number of vendors.
> > >
> > > OAM&P on native GbE is of big interest to us.  We have a
> > > 700km CWDM- 4xGbE
> > > trial just getting underway and 1500km combined 4xGbE over
> > > SONET and 4xGbE
> > > over transparent WDM about to start in Newfoundland.  We will
> > > be reporting
> > > on the initial results of these trials at NANOG in October.
> > >
> > > You will be surprised to know that the configuration that
> > > concerns us the
> > > most is the GbE over SONET  in terms of network management and OAM&P.
> > > Although the transparent DWDM and the native GbE also have
> > > challenges in
> > > this area, they are within our management domain. The GbE
> > > over SONET is a
> > > carrier "managed service".  This means the carrier offers virtual GbE
> > > connections  over a "GbE cloud" and keeps all the operations
> > > and control
> > > hidden from the user e.g buffering, flow control, etc etc .
> > > This gives us
> > > the willies because it sounds like the old "ATM cloud"
> > > service offerings
> > > where we had so many problems with IP interacting with the
> > > ATM network over
> > > which we had no control.
> > >
> > > Bill
> > >
> > >
> > >
> > > I still believe that all 3 variations of 10GbE will exist in
> > > the marketplace
> > > serving different needs and requirements
> > >
> > > Bill
> > >
> > > > -----Original Message-----
> > > > From: mittalr@xxxxxxxxxxx [mailto:mittalr@xxxxxxxxxxx]On
> > > Behalf Of Rohit
> > > > Mittal
> > > > Sent: August 4, 1999 6:10 PM
> > > > To: Bill.St.Arnaud@xxxxxxxxxx
> > > > Cc: stds-802-3-hssg@xxxxxxxx
> > > > Subject: Re: Ethernet over WANs
> > > >
> > > >
> > > > Bill:
> > > >
> > > > Now I'm confused. Isn't the OAM standard for SONET. I'm talking
> > > > about the bits
> > > > in the section and line overhead ie D1..D12. So then why is
> > > 3. being even
> > > > considered. Will we save any overhead by a new OAM protocol
> > > - I think not.
> > > >
> > > > Thanks
> > > > Rohit Mittal
> > > > Engineering, Microlinear Corp.
> > > >
> > > > > Rohit:
> > > > >
> > > > > I think you will see 3 different approaches in the marketplace for
> > > > > delivering 10GbE over the WAN:
> > > > >
> > > > > 1. 10GbE over SONET where a proprietary OAM is done at SONET layer
> > > > > 2. 10Gbe over wavelengths where a proprietary OAM is done out
> > > > of band in the
> > > > > optical channel
> > > > > 3. Native 10Gbe which would require some sort of new OAM protocol
> > > > >
> > > > > The question that has been asked as since no common
> > > standard has been
> > > > > developed for OAM in SONET, is a "standard" OAM required for
> > > > native 10GbE?
> > > > >
> > > > > Bill
> > > > > >
> > > > > >
> > > > > > Hi all,
> > > > > >
> > > > > > I recently subscribed to this list and was going
> > > through the archives
> > > > > >
> > > > > > Some people have mentioned about sending ethernet over
> > > MAN/WAN links.
> > > > > > The question I have is Ethernet doesn't have OAM
> > > features of SONET.
> > > > > > That is a critical feature for WANs (and not LANs)
> > > > > > How is that handled for 10GbE? Can you make intellegent
> > > enough DWDM
> > > > > > elements to handle that. Doesn't that by itself add
> > > overhead which is
> > > > > > comparable to SONET overhead. If so, then why is there so much
> > > > > > discussion
> > > > > > as to replace SONET by 10GbE.
> > > > >
> > > > > >
> > > > > > In packet over SONET, we use PPP which adds very little
> > > > > > overhead. Can't we use the same format for 10GbE over
> > > SONET. In that
> > > > > > case we can define the 10GbE standard without worrying
> > > about SONET .
> > > > > > Just my 2c.
> > > > > >
> > > > > > Thanks
> > > > > > Rohit Mittal
> > > > > > ~
> > > > > >
> > > >
> > >
>