BGP-MPLS VPN extension for IPv4/IPv6 Hybrid Network Defeng Li Huawei Technologies

2 2 draft-defeng-l3vpn-ipv4-ipv6-hybrid-01 Justification –IPv6 can’t take the place of IPv4 in the global network in one night, it must co-exist with IPv4 in a long period, then backbone and sites of inter-provider L3VPN will often be IPv4/IPv6 hybrid. –IPv4/IPv6 Hybrid VPN isn’t addressed elsewhere. Purpose –Proposes some methods for IPv4/IPv6 hybrid VPN –Open to accommodate other methods in the future version

3 3 draft-defeng-l3vpn-ipv4-ipv6-hybrid-01 Contents –Case 1: Both of VPN Backbone and sites are IPv4/IPv6 Hybrid Method 1 Method 2 –Case 2: IPv4 backbone with IPv4/IPv6 hybrid VPN sites Most Concepts inherited from RFC 2547bis –RD –Route Target –VRF –MP-BGP –…

4 4 draft-defeng-l3vpn-ipv4-ipv6-hybrid-01 Method 1 for Case 1

5 5 draft-defeng-l3vpn-ipv4-ipv6-hybrid-01 Route Distribution (Method 1 for Case 1) –Both IPv4 routes and IPv6 routes are distributed between CE-PE, BGP4+,IS-ISv6 and OSPFv3 can carry IPv4/ IPv6 routes simultaneously. –Every two of PEs and ASBR1 in IPv4 AS establish MP-IBGP based on IPv4; –Every two of PEs and ASBR2 in IPv6 AS establish MP-IBGP based on IPv6; –ASBR1 and ASBR2 establish MP-EBGP based on IPv6; –VPN-IPv4 routes and VPN-IPv6 routes can be piggybacked on the same MP-BGP; –PEs maintain VPN-IPv4 routes and VPN-IPv6 routes in respective VRFs, they are differentiated by the AFI of the routes received.

6 6 draft-defeng-l3vpn-ipv4-ipv6-hybrid-01 Address Requirements (Method 1 for Case 1) –Should support two AFI, 1 for IPv4 and 2 for IPv6, SAFI:128; –Two IPv4 sites communicate with IPv4 address; –Two IPv6 sites communicate with IPv6 address; –One IPv4 site and one IPv6 site communicate with IPv6 address; –IPv4 address A.B.C.D/Mask mapped to 0::A:B:C:D/(96+MASK) IPv6 address if necessary; –PEs and ASBRs should support IPv4/IPv6 dual-stack and maintain both VPN-IPv4 routes and VPN-IPv6 routes; –CEs in IPv4 sites which have relations only to other IPv4 sites can support only IPv4 protocol and maintain IPv4 VPN routes, otherwise CE should support IPv4/IPv6 dual-stack;

7 7 draft-defeng-l3vpn-ipv4-ipv6-hybrid-01 Label Distribution (Method 1 for Case 1) –Inherited from RFC 2547bis in every AS; –MP-EBGP between ASBR1 and ASBR2 distributes the labels, and LSPs in AS1 and AS2 can be sticked ; Packet Forwarding (Method 1 for Case 1) –Packets between sites-PE are forwarded following the IP protocol of the respective version(IPv4/IPv6) –In the backbone packets can be forwarded on the sticked LSP

8 8 draft-defeng-l3vpn-ipv4-ipv6-hybrid-01 Method 2 for Case 1

9 9 draft-defeng-l3vpn-ipv4-ipv6-hybrid-01 Address Requirements (Method 2 for Case 1) –Same with Method 1; Route Distribution (Method 2 for Case 1) –Every two of PEs in DAS establish MP-IBGP based on IPv4; –Every two of PEs and ASBR2 in PAS establish MP-IBGP based on IPv6; –Every PE in DAS and ASBR2 establish multi-hop MP-EBGP based on IPv4; –VPN routes need to be distributed to sites connected to neighboring AS are distributed by such multi-hop MP-EBGP; Same with method 1 in other aspects.

10 draft-defeng-l3vpn-ipv4-ipv6-hybrid-01 Case 2: IPv4 backbone and IPv4/IPv6 hybrid VPN sites

11 draft-defeng-l3vpn-ipv4-ipv6-hybrid-01 Characteristics of Case 2 –Needs no VPN-IPv6 AFI in the backbone; –PE assigns private IPv4 addresses for IPv6 site, and supports private IPv4 address NAT-PT; –Extend MP-BGP protocol by adding an Extended Community attribute: If-V6-Site to identify IPv6 sites; –IPv6 routes are mapped to IPv4 NAT-PT prefix at PE and true IPv6 routes are distributed across backbone as the “value” of If- V6-Site attribute of IPv4 NAT-PT prefix through MP-BGP;

12 draft-defeng-l3vpn-ipv4-ipv6-hybrid-01 Characteristics of Case 2 –PE maintains IPv4 routes, IPv6 mapped NAT-PT IPv4 routes and true IPv6 routes; –Communication between IPv4 site and IPv6 site needs NAT-PT translation; –Communication between two IPv6 sites use true IPv6 routes at PE; –Different routes are selected at Ingress PE according to IPv4/IPv6 types of Source/Destination sites when forwarding.

13 draft-defeng-l3vpn-ipv4-ipv6-hybrid-01 Judgement of IPv4/IPv6 sites –Whether the sites is IPv6 can be identified by the address of the interface between CE and PE, then PE can set the related fields in If-V6-Site attribute when distributing the VPN routes across backbone, and whether the remote site is IPv6 can be identified by If-V6-Site attribute attached to VPN routes received. If-V6-Site (TLV) Extended Community Attribute |T| length | | | | IPv6 Route1… | | | IPv6 Routen… |... |

14 draft-defeng-l3vpn-ipv4-ipv6-hybrid-01 What’s Next ? Can it be accepted as the baseline of wg draft? Accommodate more mechanism to this draft to address IPv4/IPv6 hybrid VPN.

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