MPLS Working Group L. Andersson
Internet-Draft Bronze Dragon Consulting
Intended status: Informational April 29, 2021
Expires: October 31, 2021
MPLS Open Design Team Questions
draft-andersson-mpls-open-dt-questions-00
Abstract
This document is a living document, meaning that during the life
timme of the MPLS Open Design Team we will put additonal questions/
issues into the document. When we find an answer amd a way to
document the issu it will be removed from this document.
Ideally when the Design Team is closed this document will be empty,
or maybe we just add a pointer to where the answer to quesstion is
documented. Thus this document will never go on to become an RFCc.
Status of This Memo
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This Internet-Draft will expire on October 31, 2021.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirement Language . . . . . . . . . . . . . . . . . . 2
2. Open DT Question List . . . . . . . . . . . . . . . . . . . . 3
2.1. Below the BoS . . . . . . . . . . . . . . . . . . . . . . 3
2.1.1. Limitations to the ability of LSR's to scan the Label
Stack . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1.2. Does flooding om maximum scanning depth of an LSR
scale? . . . . . . . . . . . . . . . . . . . . . . . 3
2.1.3. Does flooding om maximum scanning depth of an LSR
scale? . . . . . . . . . . . . . . . . . . . . . . . 3
2.1.4. First Nibble . . . . . . . . . . . . . . . . . . . . 3
2.1.5. More then on ACH after the bBoS . . . . . . . . . . . 4
2.1.6. More then one indicator? . . . . . . . . . . . . . . 4
2.2. Above the BoS . . . . . . . . . . . . . . . . . . . . . . 4
2.2.1. Resuse the ELI . . . . . . . . . . . . . . . . . . . 4
3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4
4. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 4
5. Normative References . . . . . . . . . . . . . . . . . . . . 4
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 4
1. Introduction
"Living Documents" are not commonly used in the IETF, but we have
considered it to be a good way of documenting the state of the issues
worked on by the design team.
1.1. Requirement Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
For a document that is not intended to become and RFC on the
Standards Track it might seem moot to have the requirement language
included, however it might be that a question or an answer to one of
the questions might use the BCP 14 language, so to avoid ambiguity we
left it in
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2. Open DT Question List
2.1. Below the BoS
As we start working on this document we just add new questions as we
define them. It is possible that later we will try to find a
grouping af questions based more on technical commonalities.
2.1.1. Limitations to the ability of LSR's to scan the Label Stack
Several LSRs have limitations how deep it is possible to scan the
label stack looking for certain information. If the info that are
being looked for is below this depth, is it possible to use these
LSRs for manadatoy actions?
The inormation needed for the mandatory action will never be found.
2.1.2. Does flooding om maximum scanning depth of an LSR scale?
A remedy for the issues in Section 2.1.1 has been suggested, the
maaximum scanning depth for each LSR in the network should be flooded
to all othr LSRs and used as a constraint when setting up LSPs.
Would that scasle satisfactorily.
2.1.3. Does flooding om maximum scanning depth of an LSR scale?
A remedy for the issues in Section 2.1.1 has been suggested, the
maaximum scanning depth for each LSR in the network should be flooded
to all othr LSRs and used as a constraint when setting up LSPs.
Would that scale satisfactorily.
2.1.4. First Nibble
We have indications that when we started to snoop the first nibble
after the LSE that has the BoS set to find out if the packet carried
IP (v4 or v6), there was also an agreement that "we" would never put
anything but 0b0000 or 0b0001 in that first nibble.
It is off couurse intresting to try to understand the definition of
"we" but since the aggreement were between the Internet Area and the
PWE3 working group, it is likely that it will be considered binding
for the Routing Area.
Stewart: Can you try to find out more about this and where we stand
today.
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2.1.5. More then on ACH after the bBoS
More than one ACH after the BoS. How are the ACH's separated and
related to the indicator in the label stack?
2.1.6. More then one indicator?
5. What happens when you find the first indicator? If an LSR is
scanning "the entire stack", what happens when the first indicator is
found?
2.2. Above the BoS
-
2.2.1. Resuse the ELI
-
3. IANA Considerations
This document does not make any allocations of code points from IANA
registries.
4. Acknowledgements
-
-
5. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
Author's Address
Loa Andersson
Bronze Dragon Consulting
Email: loa@pi.nu
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