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RE: Ethernet over WANs




Bill/Rohit

 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
> > > > ~
> > > >
> >
>