Re: Ethernet over WANs
Bill
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? 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
> > > > > ~
> > > > >
> > >
> >