Minutes IETF101: ila
minutes-101-ila-00
| Meeting Minutes | Identifier Locator Addressing (ila) WG | |
|---|---|---|
| Date and time | 2018-03-22 18:10 | |
| Title | Minutes IETF101: ila | |
| State | Active | |
| Other versions | plain text | |
| Last updated | 2018-04-02 |
minutes-101-ila-00
Identifier-Locator Addressing BOF
101 IETF, London, Nov 22, 2018
Local time: 18:10 - 19:10
Chairs: Joel Halpern, Samita Chakrabarti
Responsible AD: Suresh Krishnan
IAB Shepherd: Erik Nordmark
Minute takers: Uma Chunduri, Alberto Rodriguez-Natal
Jabber Scribe: Evangelos Haleplidis
Online Agenda: https://datatracker.ietf.org/meeting/101/agenda/
Etherpad: http://etherpad.tools.ietf.org/p/notes-ietf-101-ila
Agenda:
1.Chairs introduction Joel & Samita
2. Problem Statement, scope and issues Tom Herbert
3. Use cases:
a. 5G User Mobility Network Kalyani Bogineni
b. Data Center Network Tom Herbert
4. Q&A
Joel and Samita started the meeting. Samita described ILA in a
nutshell, the scope of the BOF, and she mentioned that goal is not
to go into specific solutions of ID/LOC in general but to discuss
the general problems in this area. The chairs also acknowledged
that there are other solutions which have been discussed in
various workgroups and hallway meetings in similar problem spaces.
Joel:
Scope of ILA BoF -- limited to problem space
Samita:
Proposed the agenda and the presentation started. First speaker was
Tom Herbert.
Tom:
- Goal is to provide seamless mobility for multiple use case
with high efficiency. - Use cases - Mobility related - DC
Virtualization
Network Virtualization and for converged networks
- Problems: General problems - Encapsulation is a performance and
overhead hit, tunneling
considerations need to be made for payloads.
Another issue is Identity is tied to location - this makes
mobility difficult.
Other issues:
* General encapsulation issues with any existing networks.
* Privacy in addressing - public network problems
* Mobile anchor points - single point of failure
For low latency application (AR/VR) support as well.
Sri:
Can you relate the Identity to location and whats is the
problem? Tom: Identifier is tied with location presently.
Putting these two together is an issue for mobility
Tom:
- Addressing and transformation procedure in ILA
Salient properties of ILA
- ID/LOC split
- Performs address transformation (not NAT)
- No Wire overhead (no encap or EH)
- contained within network layer
- Scope
- Data plane and control plane aspects
- LISP control plane can be leveraged or 3GPP control
plane
- Limitations
- ILA is IPv6 only
- ILA is not extensible (not for encryption and
authentication kind of use cases) - more complexity of data
plane vs. control plane and it would not support multicast,
needs special consideration for ICMP handling
- Scalability aspects
- Number of mappings, rate of update to mappings, throughput
in dataplane, managing state
in a mapping system and mapping caches
- Security Aspects
- MS contains sensitive to PII (e.g. identity, geo-locations
etc) - MS needs to be secure - Inter domain solutions
- Privacy aspects
- Privacy in addressing draft
(draft-herbert-prefix-address-privacy), privacy vs.
scalability - Locator privacy
- DOSability
- Mapping cache (potential target, cache driven..)
- Virtualization use case
- DC virtualization (every task gets is own IP address..)
- Network Virtualization (tenant isolation, IPv4 to IPv6
address translation)
Dave Allen: How identifiers are assigned - perhaps these need to be
unique? Tom: ILA protocol draft appendix has some ideas - for DC we
took separate IPv6 address prefix range.
Address assignments in DC is based on registry +timestamp.
Hopefully mapping systems can provide address collision
detection
Erik Nordmark: Interoperability with current IPv6 ?
Tom: In the internet they don't know if address got ILA
transformation, it just looks like normal
Ipv6 address
Erik KLein(on jabber): How does an supported UE get their ID? --
ie, UE and locator node interaction
Answer: Anycast address is used for UE and locator
interaction. Cost is 20 bits.
Dave Allen : Did not see whole set of requirements and usecases
(for example, BBF 5G Broadband) Suresh K : Goal for this BOF is to
understand the problem
Dino - Clarification required: How destination address can be
correctly mapped? Margaret - Understands the two usecases
- She points to some past work from 2008 which reveals
issues with ICMP, zones,
identity space for different address scopes
Kalyani
=====
5G Mobility Use case
- Acknowledgements
- USe case - 3GPP architecture
- Focus in the core network
- Why ILA
- Promise of elimination of tunnel, no overhead, especially for
small packets - with 5G it's network densification - reduces
backhaul capacity - ILA promises anchor-less mobility and
simplifies network, reduce state information - support for low
latency applications (reduced packet processing, no additional
network functions
needed at network edge)
- 5G Protocol stack with ILA
- Proposed architecture for ILA in REL16
- ILA as network slice with ILA-M at service based 3GPP
control plane and UPFs as ILA-N
and ILA-R
- Flexible implementation ans scalability
Sri: ILA-R is still your anchor"
Kalyani: I will get to it in the next slides
Dave: Does PDU contains IPv6 address?
Kalyani: Yes
Dave: How encapsulation is removed?
Joel: Does packet starts with IPv6 address - it contains IPv6 and
GTP? Tom: PDU is IP address from UE (we modify the destination
address) - no encap
PDU is the actual packet from the user. The packets get into
the netowrk and then it gets transformed and transformed back.
Looking into the model for /64 assignments.
Joel: SIR prefixes are assigned to UEs
Arashmid: Is there any internet working plan?
Kalyani: This is only for IPv6 ILA
Margeret: Fred baker did the checksum neutral mapping. What happens
in case of dynamic routing or async mapping? Kalyani- I would come
back
====
- Co-existence of mobility and security use existing schemes
- Anchorless mobility
- Going to the internet (both uplink and downlink)
- UE to UE communication uses ILA-N cache
Margeret: Didn't get the transformation
Joel: we are running out of time .. take it towards the end
- Recommendations
Huan Huawei: It does address the mobility. It doesn't address the
QFI aspect. in the GTP we have this Kalyani: This is only for iLA
slice Huan Huawei: Then this could be used for only default QoS
BoF Questions:
==========
Jabber: How does this support /64 allocation
Tom: With /64, upper 64 bits are used for both addess and
identifier; Identifier is local.
Around 20 bits for identifier and remaining for network
Dave A: I know
what ILA can address in some use cases but the requirements
are not laid out for each
Suresh: We want to see, people see this as a problem or not..
Dave: But don't rush off
Mays AL-Naday: If you don't support and any cast how this can
fit in some use cases Tom: This goes under requirements for
that particular use case. Native multicasting is
interesting as that uses source address.
Mays AL-Naday: So u agree multicast is important in some cases
- any cast?? Tom: Any cast need further work. An encoding can
support multicast -
as a whole solution, we need to suport multicast
Lorenzo: This is a great fit for DC but not clear on the scope.
The earlier slide doesn't work
This is 3 orders of magnitude backwards, this
solution doesn't work
Kalyani: This is only for access network..
Joel: Documents have described a workable way to address this
(scalability) Lorenzo: This can make it work actually Dino: If
a SIR prefix is a source in the pkt - for the return packet
how do you know if
this is source or destination
Tom: Source is not translated
NTTE: What is the exact difference between ILA and ICN?
Joel: these two are very different
Tony Li: You are changing the fundamental architecture of host
without changing the network.
Why not bite the bullet and change the fundamental
architecture?
Tom: How do you solve the anchorless mobility. For DC use case,
mobility case is very simple.
It is nice to not to change the architecture completely.
Tony: You are trying to solve multi-homing, mobility and
seperating identifier through out
the stack
Joel: We are not comparing alternatives
Margeret: I understood the 2 use cases. I understood the
intended the scope.
draft-wasserman-roundtrip in 2008, and encountered multiple
problems - like you don't have zones in the address space;
these issues are not properly clarified in the draft
Tom: Transforming the destination address and routing the packet
Margeret: How do you find the transformer
Tom: ICMP is tricky, not beilving in global identifier spaces,
identifiers are gonna
be localized. Assume this is going to be contained.
Margeret: How does this get into mapped again? You have to
control the whole thing Padma: I do understood the problem
space. Couple of clarifications. Privacy was a big topic
on the mapping system. Long lived identity problem -
how this is handled
Tom: Identity is little bit a different - identity should not
be visible on the packet and
we should not ties the identifiers
Padma: Is mapping system requirements are same as IDeas?
Tom: Requirements are orthogonal and there are some similarities
Sri: GTP-U does identifier, qos bits and bunch of
other things. How are those other things supported?
Kalyani: ILA mobility doesn't take all advanced features but
rather only for IoT and low
latency slices
Erik Nordmark: If you care about ingress filtering then you
need to consider both types of addresses
(SIR prefix and regular address)
At the very end a few questions were asked by co-chair Joel Halpern
in order to sense the room:
Joel: Do people understand the problem space described in
this BOF meeting - Strong positive hum Joel : Hum if you
didn't understand the problem space - no hum heard
Joel: Scoping - folks understood the scope?
Low humming sound
Joel did not ask about whether the crowd understood the
usecases as he mentioned
that it was obvious not everyone understood the usecases.
Suresh: Please do send the comments on the list, we can flush it
out with further discussions.
Positive humm for first question is the key. Thanks everyone.
Meeting adjourned.