> -----邮件原件----- > 发件人: mpls [mailto:mpls-bounces@xxxxxxxx] 代表 Gregory Mirsky > 发送时间: 2014年1月11日 2:24 > 收件人: Eggert, Lars; Joel Halpern > 抄送: mpls@xxxxxxxx; IETF > 主题: Re: [mpls] Last Call: <draft-ietf-mpls-in-udp-04.txt> (Encapsulating MPLS > in UDP) to Proposed Standard > > Hi Lars, > I think that " The whole point of running MPLS is to create networks in which > paths are provisionable, so this is usually not an issue." is only partially correct. > LDP-based MPLS network is not provisionable and LSPs follow IP best route > selection. Explicit signaling of LSP is achievable in (G)MPLS by using RSVP(-TE) > signaling. +1. With the replacement of a LDP-based LSP tunnel by an IP-based tunnel (e.g., MPLS-in-GRE, MPLS-in-IP or MPLS-in-UDP), the path that the traffic travels through is not changed at all. Best regards, Xiaohu > Regards, > Greg > > -----Original Message----- > From: mpls [mailto:mpls-bounces@xxxxxxxx] On Behalf Of Eggert, Lars > Sent: Friday, January 10, 2014 8:10 AM > To: Joel Halpern > Cc: mpls@xxxxxxxx; IETF > Subject: Re: [mpls] Last Call: <draft-ietf-mpls-in-udp-04.txt> (Encapsulating > MPLS in UDP) to Proposed Standard > > Hi, > > On 2014-1-10, at 16:36, Joel M. Halpern <jmh@xxxxxxxxxxxxxxx> wrote: > > 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? > > we've been rehashing this discussion several times over the years, e.g., for PWE, > AMT, etc. In order to carry fixed-rate or otherwise non-congestion-controlled > traffic over unprovisioned general Internet paths, there needs to be some sort of > basic congestion control mechanism, like a circuit breaker. > > The whole point of running MPLS is to create networks in which paths are > provisionable, so this is usually not an issue. But if you start sticking MPLS inside > of UDP, those packets can go anywhere on the net, so you need mechanisms to > control the rate of that traffic if it causes congestion, or at the very least you > need to be able to stop the traffic if it creates severe congestion. > > Lars > _______________________________________________ > mpls mailing list > mpls@xxxxxxxx > https://www.ietf.org/mailman/listinfo/mpls