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LISP BOF Update. draft-farinacci-lisp-08.txt Dino Farinacci, Dave Meyer, Vince Fuller, Darrel Lewis, Scott Brim, Dave Oran IETF Dublin - July 2008. Agenda. Overview of LISP Changing Mapping Database Entries Support for Mixed Locators Spec changes between -06 to -08 Open Issues. - PowerPoint PPT Presentation
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LISP BOF UpdateLISP BOF Updatedraft-farinacci-lisp-08.txt
Dino Farinacci, Dave Meyer, Vince Fuller, Darrel Lewis,Scott Brim, Dave Oran
IETF Dublin - July 2008
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 22
AgendaAgenda
• Overview of LISP• Changing Mapping Database Entries• Support for Mixed Locators• Spec changes between -06 to -08• Open Issues
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 33
LISP Internet DraftsLISP Internet Draftsdraft-farinacci-lisp-08.txtdraft-fuller-lisp-alt-02.txtdraft-lewis-lisp-interworking-01.txtdraft-farinacci-lisp-multicast-00.txtdraft-meyer-lisp-eid-block-01.txt
draft-mathy-lisp-dht-00.txtdraft-iannone-openlisp-implementation-01.txtdraft-brim-lisp-analysis-00.txt
draft-meyer-lisp-cons-04.txtdraft-lear-lisp-nerd-04.txtdraft-curran-lisp-emacs-00.txt
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 44
LISP Problem StatementLISP Problem Statement• Improve site multi-homing
– Allow site control ingress traffic paths– Avoid renumbering by providing for portable addresses– Do it with lower OpEx
• Improve Traffic Engineering for ISPs– Use level of indirection rather than more specific injection
• Reduce core routers routing table size• Aid in IPv4 to IPv6 transition• Provide Server Load Balancing in Data Center• Some form of mobility
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 55
LISP ConceptuallyLISP Conceptually• IPv4 and IPv6 addresses have overloaded semantics
• LISP separates Location from ID• Introduces 2 address spaces:
– Endpoint IDs (EIDs)– Routing Locators (RLOCs)
• Use 32-bit EIDs for IPv4 from registry allocation
• Use 128-bit EIDs for IPv6 from registry allocation
• Use topological addresses for Locators from ISP address block allocations
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 66
Multi-Level Addressing
Provider A10.0.0.0/8
Provider B11.0.0.0/8
S EIDs are inside of sites
RLOCs used in the core
R2R1
1.0.0.0/8
10.0.0.1 11.0.0.1
Mapping Database Entry:
1.0.0.0/8 -> (10.0.0.1, 11.0.0.1)
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 77
LISP is Map-n-EncapLISP is Map-n-Encap
Host Stack:supplies EIDs
LISP Router:
supplies RLOCs
by adding new
header
EID-prefix: 2.0.0.0/8
Locator-set (RLOCs):
12.0.0.2, priority: 1, weight: 50
13.0.0.2, priority: 1, weight: 50
Mapping Entry:
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 88
LISP Solution SpaceLISP Solution Space
• LISP - Locator/ID Separation Protocol– Network-based solution– No changes to hosts whatsoever– No new addressing changes to site devices
– Very few configuration file changes– Imperative to be incrementally deployable
– Address family agnostic
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 99
Unicast Packet Unicast Packet ForwardingForwarding
Provider A10.0.0.0/8
Provider B11.0.0.0/8
S
ITR
DITR
ETR
ETR
Provider Y13.0.0.0/8
Provider X12.0.0.0/8S1
S2
D1
D2
PI EID-prefix 1.0.0.0/8 PI EID-prefix 2.0.0.0/8
DNS entry:D.abc.com A 2.0.0.2
EID-prefix: 2.0.0.0/8
Locator-set:
12.0.0.2, priority: 1, weight: 50 (D1)
13.0.0.2, priority: 1, weight: 50 (D2)
Mapping
Entry
1.0.0.1 -> 2.0.0.2
1.0.0.1 -> 2.0.0.2
11.0.0.1 -> 12.0.0.2
Legend:
EIDs -> Green
Locators -> Red
1.0.0.1 -> 2.0.0.2
11.0.0.1 -> 12.0.0.2
1.0.0.1 -> 2.0.0.2
12.0.0.2
13.0.0.2
10.0.0.1
11.0.0.1
Policy controlledby destination site
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 1010
Locator ReachabilityLocator Reachability
Provider A10.0.0.0/8
Provider B11.0.0.0/8
S
ITR
D
ITR
ETR
ETR
Provider Y13.0.0.0/8
Provider X12.0.0.0/8S1
S2
D1
D2
PI EID-prefix 2.0.0.0/8
EID-prefix: 2.0.0.0/8
Locator-set:
12.0.0.2, priority: 1, weight: 50 (D1)
13.0.0.2, priority: 1, weight: 50 (D2)
Mapping
EntryLegend:
EIDs -> Green
Locators -> Red
12.0.0.2
13.0.0.2
10.0.0.1
11.0.0.1
-> ordinal 0
-> ordinal 1
loc-reach-bits:0x0000 0003
S
S
D
D
0003
0003 D1 D2
D1 D2
7654 3210b’xxxx xxxx’
0002
D2 D2
D2 D2
X X X
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 1111
Changing Mapping Changing Mapping EntriesEntries
• A “change” is defined to be:– Adding a locator to a locator-set– Changing an existing locator’s priority or weight (for either unicast or multicast)
– Removing a locator from a locator-set
• Adding entries is simple– Append to the end, new loc-reach-bit allocated and set
– Old cachers ignore loc-reach-bit set for non-existent locator
– New cachers use new locator-set and all loc-reach-bits
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 1212
Changing Mapping Changing Mapping EntriesEntries
• Removing a locator is done by:– Set loc-reach-bit to 0– “Zero-fill” address in slot, set priority 255
– Old cachers have non-zero slot but don’t use locator since loc-reach-bit 0
– New cachers see empty 255 slot and don’t use
• Changing priority or weights– Use Clock Sweep or SMRs
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 1313
Changing Mapping Changing Mapping EntriesEntries
EID-prefix: 153.16.1.0/24, loc-reach-bits: 0x000f, locator-set:
1.0.0.1, priority: 1, weight: 25
2.0.0.2, priority: 1, weight: 25
3.0.0.3, priority: 1, weight: 25
4.0.0.4, priority: 1, weight: 25
Changed providers: 2.0.0.2 disconnect and 5.0.0.5 connects
Over time compaction may be requiredto get loc-reach-bits back!
EID-prefix: 153.16.1.0/24, loc-reach-bits: 0x001d, locator-set:
1.0.0.1, priority: 1, weight: 25
0.0.0.0, priority: 255, weight: 25
3.0.0.3, priority: 1, weight: 25
4.0.0.4, priority: 1, weight: 25
5.0.0.5, priority: 1, weight: 25
delete
add
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 1414
Locator-Set Compaction Locator-Set Compaction ChangesChanges
• Operational Mechanism– Clock Sweep
• Protocol Mechanism– Solicit Map-Requests (SMRs)
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 1515
Clock SweepClock Sweep
time
Start thechange process
24 hours
Send Map-Replies with old mapping with TTL = 1 hour
TTL = 24 cacherstime out,
TTL = 1 cachers havebeen timing out
each hour
1 hour 1 minute
Change processends
Send Map-Replies with old mapping with TTL = 1 minute
(not to scale)
TTL = 1 hour cacherstime out,
TTL = 1 minute cachers havebeen timing outeach minute
Send Map-Replies with new mapping with TTL = 24 hours
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 1616
Solicit Map-Requests Solicit Map-Requests (SMRs)(SMRs)
• Used when a site needs compaction• Sites solicit Map-Requests from active sites
– SMR-bit is in encapsulated LISP header– ITRs rate limit to control the number and rate of Map-
Requests they want to receive• Remote ITRs rate-limit Map-Requests until they get a
Map-Reply with the new database mapping entry• Nonce from SMR copied to Map-Request copied to Map-
Reply• Map-Request can be sent either on ALT or underlying
network• Local ITR keeps track of which site has new versus old
mappings for appropriate loc-reach-bit setting• No map versioning required
– Recommendation is to have only one outstanding change
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 1717
Mixed LocatorsMixed Locators
• What are mixed locators?
dr22# sh ip lisp map-cacheLISP IP Mapping Cache for VRF "default" - 1 entries240.23.0.0/24, uptime: 00:00:14, state: complete, last modified: 00:00:14 1.22.23.23, uptime: 00:00:14, state: up, priority/weight: 1/50 11.22.23.23, uptime: 00:00:14, state: up, priority/weight: 1/50
dr22# sh ipv6 lisp map-cacheLISP IPv6 Mapping Cache for VRF "default" - 1 entries0240:0023::/32, uptime: 00:22:00, state: complete, last modified: 00:22:00 dfdf:2223::0023, uptime: 00:22:00, state: up, priority/weight: 1/33 1.22.23.23, uptime: 00:22:00, state: up, priority/weight: 1/33 11.22.23.23, uptime: 00:22:00, state: up, priority/weight: 1/33
Mixed locator-set
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 1818
Mixed LocatorsMixed Locators• LISP-ALT needs to be dual-stack• Data Probes and Map-Requests are homogenous– EID needs to be in destination address
• Map-Reply is sent on the underlying network– Therefore underlying has to be dual-stack– But IPv6 is not ubiquitous so we need IPv4 Map-Replies for IPv6 Data Probes or Map-Requests
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 1919
Mixed Locators - Some Mixed Locators - Some CautionsCautions
• Locator Reachability tells you that xTR is up– Doesn’t tell you what the AF path is from you to the ETR
• Hashing considerations– Destination EID hashes to AF RLOC– Source RLOC must be same AF
• Setting priorities for a mixed locator-set is difficult– Because you don’t know AF path for requesting source site
– Better to have “crossed sets”• IPv4 EIDs -> all IPv6 RLOCs (China and Japan deployments)
• IPv6 EIDs -> all IPv4 RLOCs (US deployments)
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 2020
Mixed Locators are Mixed Locators are UsefulUseful
Provider A10.0.0.0/8
Provider B11.0.0.0/8
S
ITR
DITR
ETR
ETR
Provider Y13.0.0.0/8
Provider X12.0.0.0/8S1
S2
D1
D2
12.0.0.2
13.0.0.2
10.0.0.1
11.0.0.1
IPv4 Internet
IPv6-onlyIPv6-only
Legend:
EIDs -> Green
Locators -> Red
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 2121
Mixed Locators are Mixed Locators are UsefulUseful
Provider A10.0.0.0/8
Provider B11.0.0.0/8
SITR
DITR
ETR
ETR
Provider Y13.0.0.0/813::/16
Provider X12.0.0.0/8S1
S2
D1
D2
12.0.0.2
13.0.0.2
10.0.0.1
11.0.0.1
Partly Dual-Stack Internet
IPv6-only
Dual-stack
13::.21
13.0.0.22
S
D
Dual-stack
E2E1
IPv4IPv
6 IPv6
IPv4/IPv6
IPv4/IPv6
IPv4/IPv6Legend:
EIDs -> Green
Locators -> Red
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 2222
Spec Diffs between -06 to Spec Diffs between -06 to -08-08
• Lots of clarification text from many reviewers
• Clearly specify only 2 LISP headers can be prepended– First one for Loc/ID split by CPE router– Second one for TE by ISP router
• Add SMR-bit to data header and Map-Request– Steal a loc-reach-bit
• Specify how to select a source UDP port number
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 2323
• Added mpriority and mweight– So locator selection can be different for unicast or multicast flows
• Updated section on LISP-Multicast to summarize details in draft-farinacci-lisp-multicast-00.txt
• When ITR receives ICMP unreachable– It may originate one to the source host inside of its site
• Add section on locator hashing for equal-priority locators
• Add sections for Clock Sweep and SMRs• Updated milestone section
Spec Diffs between -06 to Spec Diffs between -06 to -08-08
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 2424
Rough Set of Rough Set of MilestonesMilestones
1. This draft will be the draft for interoperable implementations to code against. Interoperable implementations will be ready summer of 2008.
2. Continue pilot deployment summer of 2008 using LISP-ALT as the database mapping mechanism.
3. Continue prototyping other database lookup schemes, be it DNS, DHTs, CONS, ALT, NERD, or other mechanisms.
4. Implement the LISP Multicast draft [MLISP].
5. Research more on how policy affects what gets returned in a Map- Reply from an ETR.
6. Continue to experiment with mixed locator-sets to understand how LISP can help the IPv4 to IPv6 transition.
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 2525
AccomplishmentsAccomplishments 1. A unit- and system-tested software switching implementation has been completed on cisco NX-OS for this draft for both IPv4 and IPv6 EIDs using a mixed locator-set of IPv4 and IPv6 locators.
2. A unit- and system-tested software switching implementation on cisco NX-OS has been completed for draft for [ALT].
3. A unit- and system-tested software switching implementation on cisco NX-OS has been completed for draft [INTERWORK]. Support for IPv4 translation is provided and PTR support for IPv4 and IPv6 is provided.
4. The cisco NX-OS implementation supports an experimental mechanism for slow mobility.
5. Dave Meyer, Vince Fuller, Darrel Lewis, Greg Shepherd, and Andrew Partan continue to test all the features described above on a dual-stack infrastructure.
6. Darrel Lewis and Dave Meyer have deployed both LISP translation and LISP PTR support in the pilot network. Point your browser to http://www.lisp4.net to see translation happening in action so your non-LISP site can access a web server in a LISP site.
7. Soon http://www.lisp6.net will work where your IPv6 LISP site can talk to a IPv6 web server in a LISP site by using mixed addres- family based locators.
8. An public domain implementation of LISP is underway. See [OPENLISP] for details.
9. A cisco IOS implementation is underway which currently supports IPv4 encapsulation and decapsulation features.
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 2626
Open IssuesOpen Issues• Experiment with more-specific mappings and policy-
based Map-Reply priority changing • ISP resident TE-xTR functionality with another
“multi-level LISP” hierarchy• Firm up details on LISP-Multicast• LISP can do some form of mobility
– More specific state only at edges in xTRs– Can we extend it for secure and graceful handoff
• Continue prototyping ideas and deploying on pilot network
• Interoperability testing of NX-OS, IOS, and OpenLISP
LISP BOF UpdateLISP BOF Update IETF Dublin - July 2008IETF Dublin - July 2008 Slide Slide 2727