Tecnico Electronico

Routing in IPv6
• Routing in IPv6 is unchanged from IPv4:
IPv6 has 2 types of routing protocols: IGP and EGP IPv6 still uses the longest-prefix match routing algorithm

• IGP

IPv6 Routing Protocols
ISP/IXP Workshops

RIPng (RFC 2080) Cisco EIGRP for IPv6 OSPFv3 (RFC 2740) Integrated IS-ISv6 (draft-ietf-isis-ipv6-05) IS-

• EGP : MP-BGP4 (RFC 2858 and RFC 2545) MPCisco ISP Workshops
©2005, Cisco Systems, Inc. All rights reserved.

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Cisco ISP Workshops

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RIPng

EIGRP for IPv6

• For the ISP industry, simply don’t go here • ISPs do not use RIP in any form unless there is absolutely no alternative
And there usually is

• Cisco EIGRP has had IPv6 protocol support added • Uses similar CLI to existing IPv4protocol support • Easy deployment path for existing IPv4 EIGRP users • In EFT images, coming soon to 12.3T

• RIPng was used in the early days of the IPv6 test network
Sensible routing protocols such as OSPF and BGP rapidly replaced RIPng when they became available

Cisco ISP Workshops

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Cisco ISP Workshops

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OSPFv3 overview

Differences from OSPFv2
• Runs over a link, not a subnet

• OSPFv3 is OSPF for IPv6 (RFC 2740) • Based on OSPFv2, with enhancements • Distributes IPv6 prefixes • Runs directly over IPv6 • Ships-in-the-night with OSPFv2

Multiple instances per link

• Topology not IPv6 specific
Router ID Link ID

• Standard authentication mechanisms • Useslink local addresses • Generalized flooding scope • Two new LSA types

Cisco ISP Workshops

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Cisco ISP Workshops

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OSPFv3 configuration example

ISIS Standards History
• IETF ISIS for Internets Working Group

Router1# interface Ethernet0 ipv6 address 2001:1:1:1::1/64 ipv6ospf 1 area 0 interface Ethernet1 ipv6 address 2001:2:2:2::2/64 ipv6 ospf 1 area 1 ipv6 router ospf 1 router-id 1.1.1.1 area 1 range 2001:2:2::/48

Area 0
Router2

• ISO 10589 specifies OSI IS-IS routing protocol for CLNS traffic
Tag/Length/Value (TLV) options to enhance the protocol A Link State protocol with a 2 level hierarchical architecture.

LAN1: 2001:1:1:1::/64
Eth0 Router1 Eth1• RFC 1195 added IP support, also known as Integrated IS-IS (I/ISIS)
I/IS-IS runs on top of the Data Link Layer Requires CLNP to be configured

LAN2: 2001:2:2:2::/64

• Internet Draft defines how to add IPv6 address family support to IS-IS
www.ietf.org/internet-drafts/draft-ietf-isis-ipv6-06.txt

Area 1

• Internet Draft introduces Multi-Topology concept for IS-ISwww.ietf.org/internet-drafts/draft-ietf-isis-wg-multi-topology-07.txt
Cisco ISP Workshops
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Cisco ISP Workshops

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IS-IS for IPv6

Cisco IOS IS-IS dual IP configuration

• 2 Tag/Length/Values added to introduce IPv6 routing • IPv6 Reachability TLV (0xEC) External bit Equivalent to IP Internal/ExternalReachability TLV’s • IPv6 Interface Address TLV (0xE8) For Hello PDUs, must contain the Link-Local address For LSP, must only contain the non-Link Local address • IPv6 NLPID (0x8E) is advertised by IPv6 enabled routers
Dual IPv4/IPv6 configuration. Redistributing both IPv6 static routes and IPv4 static routes.
9 Cisco ISP Workshops
© 2005, Cisco Systems, Inc. All rights reserved.

LAN1:2001:0001::45c/64
Ethernet-1

Router1# interface ethernet-1 ip address 10.1.1.1 255.255.255.0 ipv6 address 2001:0001::45c/64 ip router isis ipv6 router isis interface ethernet-2 ip address 10.2.1.1 255.255.255.0 ipv6 address 2001:0002::45a/64 ip router isis ipv6 router isis router isis address-family ipv6 redistribute static exit-address-family net 42.0001.0000.0000.072c.00 redistribute static...