Re: 10GE data rate?
Bill,
I'm having a hard time trying to figure our where you're headed with the first
paragraph of your note. Somehow you're suggesting that a router may be made less
expensive if all router interfaces were OC rate.
The answer to your question about a router requiring much more processing per
packet than an L2/L3 switch does is true in general. However, I don't see how,
based on OC-192 vs. exactly 10 Gbps rate alone, that an OC rate router card would
be cheaper. Please explain your reasoning.
I believe that your second paragraph focuses on my 10 Gbps Ethernet WAN PHY
alternative (#3) as a means for transporting Ethernet over the WAN. Please bear in
mind that this alternative may provide significant improvements in cost,
performance and operations support by leveraging the best of what Ethernet has to
offer. I believe that alternative has limited application in environments such as
extended LANs where dark fiber is available, data only networks, etc. For the bulk
of WAN applications, 10 Gbps Ethernet may be cost effectively switched, bridged or
routed to existing WAN equipment per my alternative (#1).
Roy Bynum wrote:
> Rich,
>
> I have been trying to discover why a router GbE interface costs more
> than an L2/L3 data switch GbE interface does. The answer I got was the
> router does a lot of route processing on the card in order to do the
> line speed routing of each packet. I was told that a router requires
> much more processing per packet than an L2/L3 switch does. Is this
> true? If it is, then the current high costs of OC rate router cards for
> routers would not apply if an OC rate was applied to 10GbE.
>
> By the way rich, who is going to pay for the non-telephony standard
> support systems, applifiers, regenerators, etc. that would have to be
> developed for a non-OC rate long distance version of 10GbE. Better yet,
> how many people would it take to support a single optical path that
> spaned the globe that could not be managed globally?
>
> Thank you,
> Roy Bynum
>
> Rich Taborek wrote:
> >
> > In an early note to the HSSG Speed reflector, I summarized my view of all
> > schemes discussed thus far to support the WAN at Ethernet rates of ~10 Gbps.
> > I'll repost that summary here to make it available to the larger HSSG
> > reflector. The three schemes I have come up with are:
> >
> > 1) Legacy: 10Gbps Ethernet switched/bridged/routed to Sonet. We simply need
> > to specify a 10 Gbps PHY to make this fly.
> >
> > 2) SONET-based PHY: A new Ethernet PHY compatible with OC-192 SONET that
> > connects directly to the Ethernet MAC, which runs at SONET OC-192 rates.
> > This is the new PHY suggested by Paul. Looking forward, the next higher
> > Ethernet speed variant would likely be OC-768.
> >
> > 3) 10 Gbps Ethernet WAN PHY: A new Ethernet PHY supporting WAN dark fiber
> > and/or DWDM equipment, sans SONET. I believe that this is one of the options
> > proposed by Bill St. Arnaud among others.
> >
> > My scheme (3) seems to correspond with Martin's (1) and (3) below and is a
> > PHY variant which supports a data rate of exactly 10.0 Gbps. Other qualities
> > of this PHY may include any or all of the following:
> > a) Direct drive of long-haul dark fiber and/or DWDM equipment;
> > b) Simplex and/or duplex channels;
> > c) Standard Ethernet facilities for out-of-band signaling and cable plant
> > management including MAC Control frames, Auto-Negotiation, and (I hate to
> > even suggest it) Primitive Signaling using alternate "Idle" codes. Ethernet
> > out-of-band signaling capabilities are actually more extensive than most
> > protocols I'm aware of.
> >
> > (1) above seems supports the existing SONET infrastructure quite adequeately
> > and allows high performance switch/bridge/router products to be implemeted
> > in a manner of highest compatibility with the LAN and WAN.
> >
> > (2) sabove ignificantly affects the existing LAN market through its dictate
> > of SONET speeds and other peculiarities not applicable to existing LANs and
> > is a step in the wrong direction .
> >
> > (3) above takes Ethernet where no Ethernet has gone before and treads
> > directly on the existing WAN infrastructure. This latter alternative will be
> > difficult to go forward with also since the "LAN" folks consider it to be
> > outside the scope of 802, and the "WAN" folks view it as a significant
> > territorial encroachment. However, once (1) happens, the cost advantages of
> > it will inevitably drive implementations and products based on (3).
> >
> > --
> >
> > Martin Nuss wrote:
> >
> > > Roy:
> > > I wanted to get your expert opinion on a few issues that would be of
> > > interest to me as we go forward in the standard:
> > >
> > > 1) do you really believe that we need to support all the WAN OAMP
> > > features in 10GE? I would rather prefer a light-weight 10ge protocol
> > > that guarantees the lowest cost in the LAN, but make sure that it can be
> > > wrapped easily into a WAN envelope to support all the WAN features.
> > >
> > > 2) at the last meeting, Paul Bottorff as well as Mike Salzman presented
> > > approaches to a serial 10GE standard based on scrambling as opposed to
> > > block coding. Both of these could be used for a low-cost serial LAN
> > > standard, and wrapped into WAN envelopes like SONET to provide WAN OAMP
> > > features. The 10GE data rate would have to be kept to around 9.6 Gb/s
> > > to make that possible at the lowest cost. Presumably, that would
> > > accelerate the acceptance of 10GE in the WAN.
> > >
> > > 3) Alternatively, we could propose to allow for additional control
> > > fields in the 10GE standard that duplicate the functions most important
> > > for WAN apps. This may be the cleanest solution, but it will require
> > > 802.3 to venture into an area that it has not worried about before...
> > >
> > > Any thoughts?
> > >
> > > Martin
> >
> > --
> >
> > Best Regards,
> > Rich
> >
> > -------------------------------------------------------------
> > Richard Taborek Sr. Tel: 650 210 8800 x101 or 408 370 9233
> > Principal Architect Fax: 650 940 1898 or 408 374 3645
> > Transcendata, Inc. Email: rtaborek@xxxxxxxxxxxxxxxx
> > 1029 Corporation Way http://www.transcendata.com
> > Palo Alto, CA 94303-4305 Alt email: rtaborek@xxxxxxxxxxxxx
--
Best Regards,
Rich
-------------------------------------------------------------
Richard Taborek Sr. Tel: 650 210 8800 x101 or 408 370 9233
Principal Architect Fax: 650 940 1898 or 408 374 3645
Transcendata, Inc. Email: rtaborek@xxxxxxxxxxxxxxxx
1029 Corporation Way http://www.transcendata.com
Palo Alto, CA 94303-4305 Alt email: rtaborek@xxxxxxxxxxxxx