Subject: Re: [Isis-wg] Question on DCC Architecture

From: Alex Zinin <[email-masked]>
Date: Sat, 16 Dec 2000 12:26:23 -0800

Tony, Ed

 A number of companies working in the SONET area already use or are
 planning to use DCC for IP control plane [I put MPLS list back ;),
 since this question is related to GMPLS and OTN-related work].

 There are two types of IP encapsulation on DCC that I know of:
 LAP-D and PPP/HDLC. We use the second one in our SONET products.

 I think writing up an IETF document describing this would make sense.

-- 
Alex Zinin

Friday, December 15, 2000, 9:50 PM, Tony Li <[email-masked]> wrote:

> Ed,

> Welcome to the wonderful world of SONET.

>  | I am a developer of DCC for an NE. I have few questions regarding DCC
>  | architecture.
>  | 
>  | In the system that I am developing, the network between GNE and EMS/OS
>  | is IP, it is naturally for me to consider TCP/IP on the top of DCC. This
>  | architecture makes the DCN including DCC consistent, and makes the DCC
>  | implementation easy.  However, when I read the SIF document SIF-018-1998
>  | and TELCO document GR-253-CORE, I found that the OSI on DCC is a
>  | standard and TCP/IP on DCC is not. Here comes my question:
>  | 
>  | Is there any standard about TCP/IP on DCC that I don't know?  

> Nope.  It would make sense, wouldn't it?

>  | If there is no such standard, is any one or company implementing such
>  | architecture of DCC?  If there is no such standard, is any one or
>  | company writing such standard?

> I'm unaware of anyone writing such a document nor is it particularly clear
> as to where this type of feature should be standardized.  It would make
> some sense to do this in the IETF, but it's certainly not the only possible
> place.

> I do know that many folks have discussed doing this.

> Tony

> p.s. I've excluded MPLS, as I don't see the relevance...
> _______________________________________________
> Isis-wg mailing list  -  [email-masked]
> http://external.juniper.net/mailman/listinfo/isis-wg

---

From: Alex Zinin <[email-masked]>
Date: Sun, 17 Dec 2000 09:45:45 -0800

Tony,

> First, this smells much like ISO thing to do so we'd need an agreement/liason
> first from their side. That is obviously only worth pursuiting if we have
> authors commiting to provide the cycles first.

Hmmm... why do you think specification of *IP* encapsulation over SONET DCC
using "PPP over HDLC-like framing" is something ISO should do?

> Second, which workgroup ? One of the MPLS offsprings such as GSMP ;-) ? What about 
> a new one, IPSO (IP over SOnet) ? I'm joking but wouldn't be surprised
> if the joke find takers ;-) ? 

Definitely not me ;)

I think some kind of individual submission should be ok. I guess
the Internet Area is the one that logically hosts it.

Thanks,

Alex.

---

From: Jim Boyle <[email-masked]>
Date: Sun, 17 Dec 2000 20:17:52 -0700 (MST)

Tony, since you threw the bait in the water...

Apologies to the ISIS wg, as this clearly isn't their issue. I think
this is an important issue, if interoperability between the
transmission equipment utilizing the wonderful IP control plane are to
actually interoperate (which is a novel concept in some circles).

There is a relevant submission in the NSIF (NSIF-0009-038) which says
"use PPP" and then hits on some of the TLI/TMN issues.

I'd suggest directing any further discussion of this topic to IPO 
as it is within the current version of their charter.  They might be just
as happy making sure that the right progress is being made somewhere, in
this case, NSIF.

Jim

(at least I help cut the line :)

On Sun, 17 Dec 2000, Tony Przygienda wrote:

> 	thanks 
> 	-- tony

---

From: Tony Przygienda <[email-masked]>
Date: Mon, 18 Dec 2000 04:32:28 +0100 (MET)

> as happy making sure that the right progress is being made somewhere, in

yepp, I think that was the intention of my e-mail. At least one reader
got the meaning between the lines.  We have charters to follow here ;-)

On the other hand, ISIS-wg has not been unheard of taking outrageous 
issues that had to be either done very quickly, didn't fit into any other
corner of the world or were in the danger of inertia induced death in 
other, slow moving forums ;-)  This one seems to me not being either (maybe yet ;-)

	thanks

	-- tony

---

From: Tony Przygienda <[email-masked]>
Date: Sun, 17 Dec 2000 08:44:34 +0100 (MET)

thanks 

	-- tony

---

From: James Carlson <[email-masked]>
Date: Mon, 18 Dec 2000 09:59:14 -0500 (EST)

>  I think writing up an IETF document describing this would make sense.

Describing which part?  I think there are at least three separate
issues here.  One is the control plane issue (specifying the use of IP
over DCC for carrying control messages), another is the encapsulation
(for which RFCs 1332, 1661, and 1662 should do fine), and a third is
having ITU-T specify that PPP is a "legal" option for DCC.

For the first two issues, I think those are already handled.  It's
just that third one that might be an issue for some users, and I don't
think that can be done within an IETF working group.

If you're suggesting a BCP saying that IP/PPP/HDLC/DCC is a good
thing, I suppose that's possible, but I don't see what it
accomplishes.

-- 
James Carlson, Internet Engineering       <[email-masked]>
SUN Microsystems / 1 Network Drive         71.234W   Vox +1 781 442 2084
MS UBUR02-212 / Burlington MA 01803-2757   42.497N   Fax +1 781 442 1677
Second Edition now available - http://people.ne.mediaone.net/carlson/ppp

---

From: Alex Zinin <[email-masked]>
Date: Tue, 19 Dec 2000 10:34:35 -0800

James,

 I'm talking mostly about the second part.

 The question such a document (BCP or whatever status) could
 address is "how does one send IP over a SONET DCC channel?".
 The answer could be as simple as "by using RFC1662 encapsulation
 and treating D{1-3}/D{4-12} OH bytes as a synchronous stream
 of octets", i.e., not by using LAP-D, or LAP-B, or SLIP, and
 not trying to align HDLC frames within the sequence of SONET
 frames.
 
-- 
Alex Zinin

---

From: Jeff Learman <[email-masked]>
Date: Tue, 19 Dec 2000 16:41:12 -0500

>That's why I suggested a BCP instead.  I don't see it as a standards
>issue but rather a usage issue.

This is not an IETF standards issue, it's a SONET NE standards issue.
Vendors need to know what to implement to ensure the widest interoperability.
This is not the forum to discuss them, although it was a reasonable one
to ask the question in order to get the appropriate redirects (which were
provided by several responses).

Regards,
Jeff

---

From: James Carlson <[email-masked]>
Date: Tue, 19 Dec 2000 14:02:32 -0500 (EST)

>  not trying to align HDLC frames within the sequence of SONET

Note that there are no IETF documents covering, for instance, how to
carry PPP over T1 lines.  I don't consider that to be a gap that
necessarily needs to be filled.  Similarly, I think the treatment of
D1-D3 as one bit-oriented synchronous data stream (Section DCC) and
D4-D12 as another (Line DCC) is a rather obvious usage of those SONET
features that doesn't need a separate draft for interoperable use.

I don't think SLIP is a serious suggestion (is it?), since it has no
error control or protection against address misconfiguration.
LAP-D/B/F variants are possible, but similarly somewhat outside the
control of the IETF.

(If some implementations concatenate D1-D12 together, then I suppose
that could be a problem, and would need standards language, but,
again, probably not from the IETF.)