Hi Lori, > -----Original Message----- > From: Lori Jakab [mailto:lja...@ac.upc.edu] > Sent: Thursday, May 30, 2013 6:15 AM > To: Templin, Fred L > Cc: lisp@ietf.org > Subject: Re: [lisp] AD Evaluation: draft-ietf-lisp-deployment > > Hi Fred, > > On 05/29/2013 08:32 PM, Templin, Fred L wrote: > > Hi Lori, > > > >> -----Original Message----- > >> From: Lori Jakab [mailto:lja...@ac.upc.edu] > >> Sent: Wednesday, May 29, 2013 9:58 AM > >> To: Templin, Fred L > >> Cc: Paul Vinciguerra; Lori Jakab; Brian Haberman; draft-ietf-lisp- > >> deploym...@tools.ietf.org; lisp@ietf.org > >> Subject: Re: [lisp] AD Evaluation: draft-ietf-lisp-deployment > >> > >> On 05/28/2013 11:38 PM, Templin, Fred L wrote: > >>>> -----Original Message----- > >>>> From: Paul Vinciguerra [mailto:pvi...@vinciconsulting.com] > >>>> Sent: Tuesday, May 28, 2013 12:58 PM > >>>> To: Templin, Fred L; Lori Jakab; Brian Haberman > >>>> Cc: draft-ietf-lisp-deploym...@tools.ietf.org; lisp@ietf.org > >>>> Subject: RE: [lisp] AD Evaluation: draft-ietf-lisp-deployment > >>>> > >>>>> "Encapsulation results in an end-to-end path MTU of less than > >>>>> 1500 bytes, if encapsulated packets need to travel over links > >>>>> with MTU lower than 1500 bytes + LISP encapsulation overhead." > >>>>> > >>>>> Thanks - Fred > >>>>> fred.l.temp...@boeing.com > >>>>> > >>>> [PV] > >>>> How about > >>>> "Packet Encapsulation may exceed the MTU of the underlying > physical > >>>> media. To address the MTU constraints of a given physical media, > >> the > >>>> MTU of the original payload may need to be reduced or be > fragmented > >> and > >>>> encapsulated in multiple packets." > >>> LISP and other tunnel types need to concern themselves with the > path > >>> MTU between the tunnel ingress and egress, so it is about more than > >>> just the underlying physical media of the first hop into the > tunnel. > >> I think the wording by Brian is both clear and concise, and > addresses > >> your concerns (doesn't use "may" and refers to the end-to-end path). > >> Unless there is strong objection, I will use that wording. > > Almost. Suggest changing Brian's wording slightly as follows: > > > > "Encapsulation increases the amount of overhead associated with > each > > packet. For LISP, this added overhead decreases the effective > > end-to-end path MTU." > > > > Reason is that this statement is true for LISP, but not necessarily > > true for all other tunnel types. > > I tried finding a tunneling protocol where it isn't true, but I came up > empty. Can you please give an example of a tunnel where the > encapsulation overhead does not result in a decrease of the E2E PMTU? > Even if the subject matter is LISP, and even if there is an exception, > I > wouldn't single it out when *most* tunneling protocols have the same > issue.
SEAL is an example of a tunnel type where the added overhead does not decrease the effective end-to-end path MTU for MTUs up to 1500 bytes. Another example is CAPWAP. So, maybe say: "For LISP and many other tunnel types, this added overhead decreases the effective end-to-end path MTU." Thanks - Fred fred.l.temp...@boeing.com > -Lori > > > > > Thanks - Fred > > fred.l.temp...@boeing.com > > > > > >> Thanks, > >> -Lori _______________________________________________ lisp mailing list lisp@ietf.org https://www.ietf.org/mailman/listinfo/lisp
