ietf
[Top] [All Lists]

Re: Last Call: <draft-ietf-mpls-in-udp-04.txt> (Encapsulating MPLS in UDP) to Proposed Standard

2014-01-10 09:37:18
Maybe I am completely missing things, but this looks wrong.
If the MPLS LSP is carrying fixed rate pseudo-wires, adding congestion
control will make it more likely that the service won't work.  Is that
really the goal?

We do not perform congestion control on MPLS LSPs.
Assuming that a UDP tunnel is carrying just MPLS and was established
just for MPLS, why would we expect it to behave differently than an MPLS
LSP running over the exact same path, carrying the exact same traffic?

Yours,
Joel

On 1/10/14 3:47 AM, Eggert, Lars wrote:
Hi,

that sounds good. What congestion control are you going to be specifying for 
your tunnel?

Lars

On 2014-1-10, at 4:46, Xuxiaohu <xuxiaohu(_at_)huawei(_dot_)com> wrote:

Hi Lars,

Thanks a lot for your comments.

I wonder whether the following modified text for Congestion Consideration 
section is OK from your point of view:

Since the MPLS-in-UDP encapsulation causes MPLS packets to be forwarded 
through "UDP tunnels", the congestion control guidelines for UDP tunnels as 
defined in Section 3.1.3 of [RFC5405] SHOULD be followed. Specifically, MPLS 
can carry a number of different protocols as payloads. When the payload 
traffic is IP-based and congestion-controlled, the UDP tunnel SHOULD NOT 
employ its own congestion control mechanism, because congestion losses of 
tunneled traffic will already trigger an appropriate congestion response at 
the original senders of the tunneled traffic. When the payload traffic is 
not known to be IP-based, or is known to be IP-based but not 
congestion-controlled, the UDP tunnel SHOULD employ an appropriate 
congestion control mechanism. Furthermore, because UDP tunnels are usually 
bulk-transfer applications as far as the intermediate routers are concerned, 
the guidelines as defined in Section 3.1.1 of [RFC5405] SHOULD apply.

Best regards,
Xiaohu

-----邮件原件-----
发件人: mpls [mailto:mpls-bounces(_at_)ietf(_dot_)org] 代表 Eggert, Lars
发送时间: 2014年1月8日 18:22
收件人: IETF
抄送: mpls(_at_)ietf(_dot_)org
主题: Re: [mpls] Last Call: <draft-ietf-mpls-in-udp-04.txt> (Encapsulating 
MPLS
in UDP) to Proposed Standard

Hi,

On 2014-1-2, at 16:14, The IESG <iesg-secretary(_at_)ietf(_dot_)org> wrote:
- 'Encapsulating MPLS in UDP'
<draft-ietf-mpls-in-udp-04.txt> as Proposed Standard


this document needs to describe how it addresses the issues raised in BCP145
(RFC5405). It already contains some text about messages sizes and congestion
considerations, which is great. Unfortunately, the text about congestion
considerations is not fully in line with RFC5405.

Lars


<Prev in Thread] Current Thread [Next in Thread>