Subject: Re: [mpls] Last Call: <draft-ietf-mpls-tp-use-cases-and-design-06.txt>

From: "Luyuan Fang (lufang)" <[email-masked]>
Date: Tue, 2 Apr 2013 01:05:27 +0000

Hi Russ,

Thanks for your comments, very good points.
Sorry for the delay in replying, I was out of office.

The following is my proposed text for replacing the current first
paragraph of section 1.2.

Traditional transport technologies include SONET/SDH, TDM, and ATM. There
is a transition away from these transport technologies to new packet
technologies.
In addition to the ever increasing demand for bandwidth, the packet
technologies offer these key advantages:

Bandwidth efficiency: Transport technologies supports fixed Bandwidth
only, no packet statistical multiplexing, bandwidth is reserved in
transport
whether used or not by clients. Packet technologies support statistical
multiplexing,
this is the most important motivation for the transition from traditional
transport technologies to packet technologies. The proliferation of new
distributed applications which communicate with servers over the network
in a
bursty fashion has been driving the adoption of packet transport
techniques, since
multiplexing of bursty sources is far more efficient over traditional
circuit-based
TDM technologies.

Flexible data rate connections: Traditional transport connection
granularity
is limited to the rigid PDH or SONET hierarchy (e.g., DS1, DS3, OC3, OC12,
etc.).
Packet technologies support flexible data rate connections. The support of
finer data rate granularity is important for today¹s wireline and wireless
services and applications.

QoS support: While traditional transport, such as TDM transport has
very limited QoS support, packet transport can provide needed QoS
treatment for
IPTV, Voice and Video over IP applications.

The root cause for transport moving to packet transport is the shift
of application from TDM to packet. For example, Voice TDM to VoIP; Video to
Video over IP; TDM access lines to Ethernet; TDM VPNs to IP VPNs and
Ethernet
VPNs. In addition, network convergence and technology refreshes demand for
common and flexible infrastructure that provides multiple services.

Thanks,
Luyuan

-----Original Message-----
From: Russ Housley <[email-masked]>
Date: Saturday, March 23, 2013 3:16 PM
To: "[email-masked]" <[email-masked]>
Cc: "[email-masked]" <[email-masked]>
Subject: Re: [mpls] Last
Call:	<draft-ietf-mpls-tp-use-cases-and-design-06.txt>

>I wonder if the direction of Section 1.2 can be revised to make it more
>of an engineering document.
>
>It currently says:
>
>   In recent years, the urgency for moving from traditional transport
>   technologies, such as SONET/SDH, TDM, and ATM, to new packet
>   technologies has been rising. This is largely due to the fast growing
>   demand for bandwidth, which has been fueled by the following factors:
>   ...
>
>Please consider an approach that describes the the reasons behind the
>transition from the network operator and network user perspectives:
>
>   Traditional transport technologies include SONET/SDH, TDM, and ATM.
>   There is a transition away from these transport technologies to new
>   packet technologies. In addition to the ever increasing demand for
>   bandwidth, the packet technologies offer these advantages:
>   ...
>
>The fact that IP networks are being used for new applications and that
>the legacy devices are getting old does not motivate the transition to
>packet technologies.  The advantages that packet technologies offer for
>these new applications is the thing that needs to be highlighted here,
>even if it is just a list of bullets.
>
>It seems like the only sentence that addresses this point in Section 1.2
>is: "It streamlines the operation, reduces the overall complexity, and
>improves end-to-end convergence."
>
>Thanks,
>  Russ
>
>On Jan 28, 2013, at 3:01 PM, The IESG wrote:
>
>> The IESG has received a request from the Multiprotocol Label Switching
>>WG
>> (mpls) to consider the following document:
>> - 'MPLS-TP Applicability; Use Cases and Design'
>>  <draft-ietf-mpls-tp-use-cases-and-design-06.txt> as Informational RFC
>> 
>> The IESG plans to make a decision in the next few weeks, and solicits
>> final comments on this action. Please send substantive comments to the
>> [email-masked] mailing lists by 2013-02-11. Exceptionally, comments may
>>be
>> sent to [email-masked] instead. In either case, please retain the
>> beginning of the Subject line to allow automated sorting.
>> 
>> Abstract
>> 
>>   This document provides applicability, use case studies and network
>>   design considerations for the Multiprotocol Label Switching Transport
>>   Profile (MPLS-TP). The use cases include Metro Ethernet access and
>>   aggregation transport, Mobile backhaul, and packet optical transport.
>> 
>> The file can be obtained via
>> http://datatracker.ietf.org/doc/draft-ietf-mpls-tp-use-cases-and-design/
>> 
>> IESG discussion can be tracked via
>> 
>>http://datatracker.ietf.org/doc/draft-ietf-mpls-tp-use-cases-and-design/b
>>allot/
>> 
>> 
>> No IPR declarations have been submitted directly on this I-D.
>
>_______________________________________________
>mpls mailing list
>[email-masked]
>https://www.ietf.org/mailman/listinfo/mpls

---

From: "Doolan, Paul (NSN - US/Irving)" <[email-masked]>
Date: Tue, 2 Apr 2013 11:58:33 +0000

Hi Luyuan,

You wrote (in part):

......since multiplexing of bursty sources is far more efficient over traditional circuit-based
TDM technologies.

Which is not true and probably not what you meant. 

A better formulation might be "since packet multiplexing of traffic from bursty sources provides more efficient use of bandwidth than traditional circuit-based TDM technologies".

To be honest however, I'd cut the traditional and use only TDM (since some 'circuit' based technologies also offer packet multiplexing) so I'd reduce it to:

A better formulation might be "since packet multiplexing of traffic from bursty sources provides more efficient use of bandwidth than TDM technologies".

cheers,
pd

-----Original Message-----
From: [email-masked] [mailto:[email-masked]] On Behalf Of ext Luyuan Fang (lufang)
Sent: Monday, April 01, 2013 9:05 PM
To: Russ Housley; [email-masked]
Cc: [email-masked]
Subject: Re: [mpls] Last Call: <draft-ietf-mpls-tp-use-cases-and-design-06.txt>

Hi Russ,

Thanks,
Luyuan

---

From: "Luyuan Fang (lufang)" <[email-masked]>
Date: Tue, 2 Apr 2013 12:46:12 +0000

Works for me. Thanks, Paul.
Luyuan

-----Original Message-----
From: <Doolan>, "Paul   (NSN - US/Irving)" <[email-masked]>
Date: Tuesday, April 2, 2013 7:58 AM
To: Luyuan Fang <[email-masked]>, Russ Housley <[email-masked]>,
"[email-masked]" <[email-masked]>
Cc: "[email-masked]" <[email-masked]>
Subject: RE: [mpls] Last Call:
<draft-ietf-mpls-tp-use-cases-and-design-06.txt>

>A better formulation might be "since packet multiplexing of traffic from
>bursty sources provides more efficient use of bandwidth than traditional
>circuit-based TDM technologies".
>
>To be honest however, I'd cut the traditional and use only TDM (since
>some 'circuit' based technologies also offer packet multiplexing) so I'd
>reduce it to:
>
>A better formulation might be "since packet multiplexing of traffic from
>bursty sources provides more efficient use of bandwidth than TDM
>technologies".
>
>
>cheers,
>pd
>
>
>Subject: Re: [mpls] Last Call:
><draft-ietf-mpls-tp-use-cases-and-design-06.txt>
>
>Hi Russ,
>
>>>b