Cisco IOS IPv6 Provider Edge
Router (6PE) over MPLS
Patrick Grossetete
Cisco Systems
Cisco IOS IPv6 Product Manager
pgrosset@cisco.com
© 2001, Cisco Systems, Inc. All rights reserved.
1
Agenda
• IPv6 migration approaches enabled by
MPLS
• 6PE approach: IPv6 Provider Edge Router
over MPLS/IPv4
• Cisco IOS 6PE configuration
• Conclusions
Presentation_ID
© 2001, Cisco Systems, Inc. All rights reserved.
2
Key Markets where MPLS
will facilitate IPv6 Migration
• Wireless
2.5G/3G mobile phone, PDAs, Car’s
networks…
• Service Providers
Mobile ISPs, Greenfield ISPs, Regional ISPs
and Carriers
• Academic and Research Networks
Presentation_ID
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3
3GPP/UMTS Example
Alternative
Access
Network
IPv6 Mandated
Legacy mobile
signaling
network
Applications
& Services*)
SCP
GPRS
Access
Network
R-SGW
Mh
PS Domain
Ms
TE
MT
R
BSS/GRAN
Um
CSCF
Iu
A
Iu
TE
MT
R
Mg
Mr
Gi
Gf
Gb
Mm
Cx
EIR
MPLS offers
ATM + IP + IPv6
switching
Mw
CAP
HSS *)
Gr
MRF
Gi
Gc
SGSN
Gi
MGCF
Gi
MGW
MGW
Nb
Mc
MS Circuit
Switch
Access
Network
T-SGW *)
Iu 1
2
IM Domain
Mc
GGSN
Gn
UTRAN
Uu
Multimedia
IP Networks
CSCF
PSTN/
Legacy/External
Mc
Iu
Nc
MSC server
CS Domain
GMSC server
T-SGW *)
C
CAP
CAP
D
Applications
& Services*)
Signalling Interface
Signalling and Data Transfer Interface
Mh
HSS *)
R-SGW *)
*) those elements are duplicated for figure
layout purpose only, they belong to the same
logical element in the reference model
IM Domain is now a sub-set of the PS Domain
Presentation_ID
© 2001, Cisco Systems, Inc. All rights reserved.
4
IPv6 over MPLS
Deployment Scenarios
• Many ways to deliver IPv6 services to End Users
Most important is End to End IPv6 traffic forwarding
• Many Service Providers have already deployed
MPLS in their IPv4 backbone for various reasons
MPLS/VPN, MPLS/QoS, MPLS/TE, ATM + IP switching
• MPLS can be used to facilitate IPv6 integration
• Multiple approaches for IPv6 over MPLS:
IPv6 CE-to-CE IPv6 over IPv4 Tunnels
IPv6 over “Circuit_over_MPLS”
Native IPv6 MPLS
IPv6 Provider Edge Router (6PE) over MPLS
Presentation_ID
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5
IPv6 Tunnels configured on CE
IPv6 over IPv4 Tunnels
v6
Dual Stack
IPv4-IPv6
CE routers
IPv6
IPv4
v4
PE
P
P
PE
v6
Dual Stack
IPv4-IPv6
CE routers
OC48/192
v6
IPv6
IPv4
v4
•
•
•
•
•
•
v6
P
PE
P
IPv4
v4
PE
No impact on existing IPv4 or MPLS Core (IPv6 unaware)
Only CEs have to be IPv6-aware (Dual stack)
Mesh of IPv6 over IPv4 Tunnels CE-to-CE
Overhead: IPv4 header + MPLS header
MPLS/VPN support IPv4-native and IPv6 tunnels
Service Provider can’t delegate his IPv6 prefix to the CE routers
Presentation_ID
© 2001, Cisco Systems, Inc. All rights reserved.
6
IPv6 over “Circuit_over_MPLS”
Circuit_over_MPLS
(eg. ATM VC, FR PVC, Ethernet,…)
v6
IPv6
IPv6
routers
v6
•
•
•
•
IPv6
P
P
P
P
“Circuit”
IPv6
v6
IPv6
v6
IPv6
No impact on existing IPv4 or MPLS Core (IPv6 unaware)
Edge MPLS Routers need to support “Circuit_over_MPLS”
Mesh of “Circuit_Over_MPLS” PE-to-PE
PE routers can also be regular IPv6 Routers (IPv6 over ATM, IPv6
over FR, IPv6 over Ethernet,…) to aggregate Customer’s IPv6 routers
Presentation_ID
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7
Native MPLS Support of IPv6
MPLS Label Switch Paths for IPv6
v6
v6
IPv6
IPv6
P
P
P
P
IPv6
IPv6 MPLS
IPv6
v6
v6
IPv6
All routers are IPv6-aware
• Core Infrastructure requires full Control Plane upgrade to
IPv6
• IPv6 Routing in core
• IPv6 Label Distribution Protocol in core
• Dual Control Plane management if IPv4 and IPv6 services
Presentation_ID
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8
Agenda
• IPv6 migration approaches enabled by
MPLS
• 6PE approach: IPv6 Provider Edge Router
over MPLS/IPv4
• Cisco IOS 6PE configuration
• Conclusions
Presentation_ID
© 2001, Cisco Systems, Inc. All rights reserved.
9
IPv6 Provider Edge Router (6PE)
over MPLS
MP-iBGP sessions
v6 2001:0420::
2001:0620:: v6
145.95.0.0
v4
6PE
P
P
6PE
Dual
Dual Stack
Stack IPv4-IPv6
IPv4-IPv6 routers
routers
2001:0621::
Dual
Dual Stack
Stack IPv4-IPv6
IPv4-IPv6 routers
routers
v6
P
CE
6PE
192.76.10.0
v4
P
IPv4
MPLS
CE
•
•
•
•
v6 2001:0421::
6PE
v4
192.254.10.0
CE
IPv4 or MPLS Core Infrastructure is IPv6-unaware
PEs are updated to support Dual Stack/6PE
IPv6 reachability exchanged among 6PEs via iBGP (MP-BGP)
IPv6 packets transported from 6PE to 6PE inside MPLS
Presentation_ID
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10
6PE Overview
MP-BGP sessions
2001:0620:: v6
145.95.0.0
2001:0621::
v4
v6
IPv6
v4
v6 2001:0420::
IPv4
6PE
IPv6
P
P
P
P
6PE
v4 192.254.10.0
6PE
Dual Stack
V6:
IGP/BGP
v6 2001:0421::
IPv6
IPv4
6PE
IPv4
192.76.10.0
IPv6
Dual Stack
IGPv4
MPLS V4:
- LDPv4
- (TE v4)
V6:
IGP/BGP
IPv6 unaware
No core upgrade
Presentation_ID
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11
6PE Routing
MP-BGP advertises 2001:0421::::
MPand binds a (2nd level) label
IPv6 Next Hop is an IPv4 compatible IPv6 address
built from 192.254.10.17
2001:0420::
IGPv4 advertises
reachability of
192.254.10.17
2001:0421::
192.72.170.13
6PE-1
LDPv4 binds label
to 192.254.10.17
192.254.10.17
6PE-2
P1
P2
• Translation of v6 BGP
Next_Hop into v4address
• Recursion of this address
via IGPv4
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12
6PE Routing/Label Distribution
IGPv6 or MP-BGP
advertising
2001:0421::
2001:0420::
6PE-2 sends MP-iBGP advertisement to 6PE-1 which says:
2001:0421:: is reachable
via BGP Next Hop = 192.254.10.17 (6PE-2)
bind BGP label to 2001:0421:: (*)
IGPv4 advertises reachability
of 192.254.10.17
6PE-1
2001:0421::
192.72.170.13
6PE-2
P2
P1
LDPv4 binds label
to 192.254.10.17
192.254.10.17
IGPv6 or MP-BGP
advertising
2001:0421::
(*) The 2nd label allows operations with Penultimate Hop Popping (PHP)
(which is typically used in current MPLS networks)- it is an Aggregate label
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13
6PE Forwarding
2001:0420::
IPv6 packet
to 2001:0421::
2001:0421::
192.72.170.13
6PE-1
6PE-2
192.254.10.17
P1
Presentation_ID
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P2
14
6PE Forwarding (6PE-1)
2001:0420::
IPv6 packet
to 2001:0421::
192.72.170.13
6PE-1
IPv6 Forwarding and Label Imposition:
• 6P
6PE
E-1 receives an IPv6
IP v6 packet
• Lookup is done on IPv6 prefix
• Result is:
Labelz binded by MPMP-BGP to
2001:0421::
Label1 binded by LDP/IGPv4 to the
IPv4 address of BGP Next Hop
(6PE--2)
(6PE
2001:0421::
6PE-2
MP -BGP label IPv6 packet
MPLDP/IGPv4
label1 to 6PE6PE-2 To 2001:421:: To 2001:421::
192.254.10.17
P1
Presentation_ID
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P2
15
6PE Forwarding (P1)
IPv6-UNaware MPLS Label
Switching:
2001:0420::
IPv6 packet
to 2001:0421::
192.72.170.13
•P1 receives an MPLS packet
•Lookup is done on Label1
•Result is Label2
2001:0421::
6PE-1
6PE-2
MP -BGP label IPv6 packet
MPLDP/IGPv4
label1 to 6PE6PE-2 To 2001:421:: To 2001:421::
192.254.10.17
P2
P1
LDP/IGPv4
label2 to 6PE6PE-2
Presentation_ID
MP -BGP label
MPTo 2001:421::
© 2001, Cisco Systems, Inc. All rights reserved.
IPv6 packet
To 2001:421::
16
6PE Forwarding (P2)
IPv6-UNaware MPLS Label
Switching:
2001:0420::
IPv6 packet
to 2001:0421::
192.72.170.13
•P2 receives an MPLS packet
•Lookup is done on Label2
•Result includes Pop label (PHP)
2001:0421::
6PE-1
6PE-2
MP -BGP label IPv6 packet
MPLDP/IGPv4
label1 to 6PE6PE-2 To 2001:421:: To 2001:421::
192.254.10.17
P2
P1
LDP/IGPv4
label2 to 6PE6PE-2
Presentation_ID
MP -BGP label
MPTo 2001:421::
© 2001, Cisco Systems, Inc. All rights reserved.
IPv6 packet
To 2001:421::
MP -BGP label IPv6 packet
MPTo 2001:421:: To 2001:421::
17
6PE Forwarding (6PE-2)
MPLS Label Pop and IPv6
Forwarding :
2001:0420::
IPv6 packet
to 2001:0421::
•
•
•
192.72.170.13
6PE-1
6PE-2 receives an MPLS packet
Lookup is done on Label
Result is:
Pop the label & do IPv6 lookup
on IPv6 destination
6PE-2
2001:0421::
IPv6 packet
To 2001:421::
MP -BGP label IPv6 packet
MPLDP/IGPv4
label1 to 6PE6PE-2 To 2001:421:: To 2001:421::
192.254.10.17
P2
P1
LDP/IGPv4
label2 to 6PE6PE-2
Presentation_ID
MP -BGP label
MPTo 2001:421::
© 2001, Cisco Systems, Inc. All rights reserved.
IPv6 packet
To 2001:421::
MP -BGP label IPv6 packet
MPTo 2001:421:: To 2001:421::
18
Cisco IOS releases for 6PE
• 12.0(22)S on Cisco 12000 series
• 12.2(11)S on Cisco 7200/7400/7500 series
Next release on Cisco 7600
• 12.2(6th)T on Cisco 3600/3700/7200/7500
• Contact your Cisco Local team for latest
update
Presentation_ID
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19
6PE Standardization
• See <draft-ietf-ngtrans-bgp-tunnel-04.txt> :
“BGP Tunnelling”
• Co-authored by Cisco
• Generic solution for transport of IPv6 over
any tunnelling technique (including MPLS)
using MP-BGP
• IETF Working Group document
• 6PE is Cisco IOS implementation of “BGP
Tunnelling” over MPLS
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20
6PE Benefits
For SPs already running MPLS, 6PE approach
has many benefits:
• Core Infrastructure needs no upgrade and no
configuration change
• Upgrade only on the required edge routers (ie
upgrade of existing PEs to 6PE, or add separate 6PEs)
• IPv6 supported simultaneously with existing MPLS
services (MPLS v4_VPNs, QoS, ATM, v4 Internet, …)
è 6PE allows IPv6 to be deployed over existing
MPLS Multiservice infrastructure with marginal
operational impact/cost /risk
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21
6PE Benefits
MP-BGP sessions
2001:0620:: v6
145.95.0.0
2001:0621::
v4
6PE
v6
6PE
192.76.10.0 v4
v6IGP
MP-BGP
P
P
P
P
IPv4
MPLS
v6 2001:0420::
6PE
v6 2001:0421::
v4 192.254.10.0
6PE
IPv6 CE only has a single Routing Peer (PE) regardless of how many
remote IPv6 CEs it communicates with
No change on an IPv6 CE when remote CEs are added/removed
(reachability automatically learnt)
No tunnel/”circuit” to be configured
è 6PE offers scalable and flexible solution (benefits are analogous to
RFC2547bis layer 3 VPN solution for IPv4)
Presentation_ID
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22
6PE Benefits
MP-BGP sessions
2001:0620:: v6
v6 2001:0420::
CE
145.95.0.0
2001:0621::
v6
6PE
v6
CE
6PE
192.76.10.0 v6
P
P
P
P
IPv4
MPLS
v6 2001:0421::
6PE
v4 192.254.10.0
6PE
CE
CE
à6PE solution can be easily extended to support same
VPN services for IPv6 as currently supported for IPv4
with RFC2457bis (isolation, Internet access, QoS…)
Presentation_ID
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23
6PE Cons
MP-BGP sessions
2001:0620:: v6
v6 2001:0420::
CE
145.95.0.0
2001:0621::
v4
6PE
v6
CE
6PE
192.76.10.0 v4
P
P
P
P
IPv4
MPLS
v6 2001:0421::
6PE
v4 192.254.10.0
6PE
CE
CE
• Only makes sense where network already runs MPLS
• Requires knowledge of MPLS and BGP technologies
• Requires dual-stack and software upgrade on
existing PE or deployment of dedicated 6PE routers
Presentation_ID
© 2001, Cisco Systems, Inc. All rights reserved.
24
Agenda
• IPv6 migration approaches enabled by
MPLS
• 6PE approach: IPv6 Provider Edge Router
over MPLS/IPv4
• Cisco IOS 6PE configuration
• Conclusions
Presentation_ID
© 2001, Cisco Systems, Inc. All rights reserved.
25
6PE Configuration Commands
• Two new Commands:
router(config-router-af)# neighbor <ip-address> send-label
Enables binding and advertisement of aggregate labels when
advertising ipv6 prefixes in BGP
router(config)# mpls ipv6 source-interface <interface>
Specifies the interface from which to inherit ipv6 addresses for
locally generated packets
Presentation_ID
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26
6PE Show Commands
• Three show commands extended
show bgp ipv6 <ipv6-prefix>
displays the mpls label value advertized for the IPv6 prefix
show bgp ipv6 neighbor
displays the mpls label capability negotiated with the BGP peer
show mpls forwarding-table
6PE labels are displayed with outgoing tag as “Aggregate” and
prefix as “6PE imposition”
Presentation_ID
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27
6PE configuration
6CE
ipv6 cef
mpls label protocol ldp
6PE
Staticv6
RIPv6
ISISv6
eBGPv6
ip cef
mpls label protocol ldp
tag-switching tdp router-id
loopback0
!
interface Serial2/0
ip address 10.10.10.2
255.255.255.252
ip router isis
mpls label protocol ldp
tag-switching ip
!
Presentation_ID
mpls ipv6 source-interface Loopback0
P
mpls ldp router-id loopback0
!
interface Loopback0
ip address 10.10.20.2 255.255.255.255
ipv6 address 2003::/64 eui-64
!
router bgp 100
no synchronization
no bgp default ipv4-unicast
bgp log-neighbor-changes
neighbor 10.10.20.1 remote-as 100
neighbor 10.10.20.1 update-source Loopback0
!
address-family ipv6
neighbor 10.10.20.1 activate
neighbor 10.10.20.1 send-label
redistribute connected
redistribute rip ripv6CE1
exit-address-family
!
© 2001, Cisco Systems, Inc. All rights reserved.
28
Show bgp ipv6 <ipv6-prefix>
Router> show bgp ipv6 2003:1:1:30::/64
BGP routing table entry for 2003:1:1:30::/64, version 2
Paths: (1 available, best #1, table Global-IPv6-Table)
Not advertised to any peer
Local
::FFFF:10.10.20.1 (metric 10) from 10.10.20.1 (192.168.254.1)
Origin incomplete, metric 0, localpref 100, valid,
internal, best
Presentation_ID
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29
Show bgp ipv6 neighbor
Router> show bgp ipv6 neighbors 10.10.20.1
BGP neighbor is 10.10.20.1, remote AS 100, internal link
BGP version 4, remote router ID 192.168.254.1
BGP state = Established, up for 00:04:07
Last read 00:00:07, hold time is 180,
Neighbor capabilities:
Route refresh: advertised and received(old & new)
Address family IPv6 Unicast: advertised and received
ipv6 MPLS Label capability: advertised and received
For address family: IPv6 Unicast
BGP table version 2, neighbor version 2
Index 1, Offset 0, Mask 0x2
Route refresh request: received 0, sent 0
Sending Prefix & Label
2 accepted prefixes consume 144 bytes
Prefix advertised 1, suppressed 0, withdrawn 0
Number of NLRIs in the update sent: max 1, min 0
Presentation_ID
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30
Show mpls forwarding-table
Router> show mpls forwarding-table
Local Outgoing
Prefix
tag
tag or VC
or Tunnel Id
16
16
10.10.20.4/32
17
Pop tag
10.10.10.0/30
18
Pop tag
10.10.20.3/32
19
18
10.10.40.0/30
20
19
10.10.20.2/32
Bytes tag
switched
0
0
0
0
0
21
2080
Presentation_ID
Aggregate
IPv6
© 2001, Cisco Systems, Inc. All rights reserved.
Outgoing
interface
Se0/0
Se0/0
Se0/0
Se0/0
Se0/0
Next Hop
point2point
point2point
point2point
point2point
point2point
31
Show ipv6 route
Router> show ipv6 route
IPv6 Routing Table - 4 entries
Codes: C - Connected, L - Local, S - Static, R - RIP, B - BGP
I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea
B
2003:1:1:30::/64 [200/0]
via ::FFFF:10.10.20.1, IPv6-mpls
L
2003::205:32FF:FEC3:40E1/128 [0/0]
via ::, Loopback0
C
2003::/64 [0/0]
via ::, Loopback0
L
FE80::/64 [0/0]
via ::, Null0
Presentation_ID
© 2001, Cisco Systems, Inc. All rights reserved.
32
Agenda
• IPv6 migration approaches enabled by
MPLS
• 6PE approach: IPv6 Provider Edge Router
over MPLS/IPv4
• Cisco IOS 6PE configuration
• Conclusions
Presentation_ID
© 2001, Cisco Systems, Inc. All rights reserved.
33
Conclusions
• IPv6 migration does not “need” MPLS … but,
where MPLS is deployed, it enables attractive
approaches for IPv6 migration
• Cisco IPv6 and MPLS solutions provides the
broadest deployment scenario feature set
• Cisco’s 6PE is one such IPv6 migration approach
over IPv4 MPLS, which offers IPv6 deployment at
marginal cost/risk:
no upgrade/reconfig in IPv4/MPLS core
IPv6 simultaneously with IPv4, IPv4 VPNs, ATM,
…
Presentation_ID
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Presentation_ID
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www.cisco.com
35
© 2001, Cisco Systems, Inc.
36