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Understanding IPv6 - Addressing & Subnetting Part 3. Agenda. Global u nicast address assignment Stateless Address Autoconfiguration Stateless DHCP Stateful DHCP Other types of addresses Link Local Address Multicast Address Solicited Node Multicast. Agenda.
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Agenda Global unicast address assignment • Stateless Address Autoconfiguration • Stateless DHCP • StatefulDHCP Other types of addresses • Link Local Address • Multicast Address • Solicited Node Multicast
Agenda Global unicast address assignment • Stateless Address Autoconfiguration • Stateless DHCP • StatefulDHCP Other types of addresses • Link Local Address • Multicast Address • Solicited Node Multicast
Global Unicast Address Assignment Global Unicast Manual Dynamic IPv6 Unnumbered Stateless Autoconfiguration IPv6 Address DHCPv6 Static EUI-64 IPv6 unnumbered is similar to the IPv4 unnumbered.
Stateless Address Autoconfiguration (SLAAC) RouterA • Stateless Address Autoconfiguration (SLAAC) is an automatic method for assigning global unicast addresses to interfaces. • No need for DHCPv6 server ipv6 unicast-routing MAC: 00-19-D2-8C-E0-4C 1 NDP Router Solicitation 2 NDP Router Advertisement EUI-64
R1 ipv6 unicast-routing DHCPv6 Server • Router Solicitation and Router Advertisement messages are about communications between a host and a router. • R1(config)# ipv6 unicast-routing NDP Router Solicitation “Need information from the router” NDP Router Advertisement
R1 ipv6 unicast-routing DHCPv6 Server • Router Solicitation and Router Advertisement messages are about communications between a host and a router. • Part of ICMPv6’s Neighbor Discovery Protocol • R1(config)# ipv6 unicast-routing NDP Router Solicitation “Need information from the router” NDP Router Advertisement
R1 ipv6 unicast-routing DHCPv6 Server • Router Solicitation and Router Advertisement messages are about communications between a host and a router. • Part of ICMPv6’s Neighbor Discovery Protocol • Routers periodically send Router Advertisement messages or response to a Router Solicitation message from a host on the link. • R1(config)# ipv6 unicast-routing NDP Router Solicitation “Need information from the router” NDP Router Advertisement
RouterA ipv6 unicast-routing DHCPv6 Server • The router’s Router Advertisement can determine how the host gets its dynamic address configuration.
RouterA ipv6 unicast-routing DHCPv6 Server • RouterA(config)# ipv6 unicast-routing • The router’s Router Advertisement can determine how the host gets its dynamic address configuration. • ipv6 unicast-routing command enables router to send Router Advertisements.
RouterA ipv6 unicast-routing DHCPv6 Server 1 NDP Router Solicitation “Need information from the router” • Router Advertisements are sent periodically (Cisco default every 200 seconds) • Or in response to a Router Solicitation message.
RouterA ipv6 unicast-routing DHCPv6 Server 2 NDP Router Advertisement 1 NDP Router Solicitation “Need information from the router” • Router Advertisements are sent periodically (Cisco default every 200 seconds) • Or in response to a Router Solicitation message.
RouterA ipv6 unicast-routing DHCPv6 Server 2 NDP Router Advertisement “I’m everything you need (Prefix, Prefix-length, Default Gateway)” 1 NDP Router Solicitation “Need information from the router” • The router’s Router Advertisement can determine how the host gets its dynamic address configuration.
RouterA ipv6 unicast-routing DHCPv6 Server 2 NDP Router Advertisement “I’m everything you need (Prefix, Prefix-length, Default Gateway)” Or “Here is my information but you need to get other information such as DNS addresses from a DHCPv6 server.” 1 NDP Router Solicitation “Need information from the router” • The router’s Router Advertisement can determine how the host gets its dynamic address configuration.
RouterA ipv6 unicast-routing DHCPv6 Server 2 NDP Router Advertisement “I’m everything you need (Prefix, Prefix-length, Default Gateway)” Or “Here is my information but you need to get other information such as DNS addresses from a DHCPv6 server.” Or “I can’t help you. Ask a DHCPv6 server for all your information.” 1 NDP Router Solicitation “Need information from the router” • The router’s Router Advertisement can determine how the host gets its dynamic address configuration.
RouterA ipv6 unicast-routing MAC: 00-19-D2-8C-E0-4C 1 NDP Router Solicitation EUI-64
RouterA ipv6 unicast-routing MAC: 00-19-D2-8C-E0-4C 1 NDP Router Solicitation 2 NDP Router Advertisement From: FE80::1 (Link-local address) EUI-64
RouterA ipv6 unicast-routing MAC: 00-19-D2-8C-E0-4C 1 NDP Router Solicitation 2 NDP Router Advertisement From: FE80::1 (Link-local address) To: FF02::1 (All-hosts multicast) EUI-64
RouterA ipv6 unicast-routing MAC: 00-19-D2-8C-E0-4C 1 NDP Router Solicitation 2 NDP Router Advertisement From: FE80::1 (Link-local address) To: FF02::1 (All-hosts multicast) Prefix: 2001:DB8:AAAA:1:: EUI-64
RouterA ipv6 unicast-routing MAC: 00-19-D2-8C-E0-4C 1 NDP Router Solicitation 2 NDP Router Advertisement From: FE80::1 (Link-local address) To: FF02::1 (All-hosts multicast) Prefix: 2001:DB8:AAAA:1:: Prefix-length: /64 EUI-64
RouterA ipv6 unicast-routing MAC: 00-19-D2-8C-E0-4C 1 NDP Router Solicitation 2 NDP Router Advertisement From: FE80::1 (Link-local address) To: FF02::1 (All-hosts multicast) Prefix: 2001:DB8:AAAA:1:: Prefix-length: /64 EUI-64 3 Prefix: 2001:DB8:AAAA:1:: Prefix-length: /64
RouterA ipv6 unicast-routing MAC: 00-19-D2-8C-E0-4C 1 NDP Router Solicitation 2 NDP Router Advertisement From: FE80::1 (Link-local address) To: FF02::1 (All-hosts multicast) Prefix: 2001:DB8:AAAA:1:: Prefix-length: /64 EUI-64 3 Prefix: 2001:DB8:AAAA:1:: Prefix-length: /64 EUI-64 Interface ID: 02-19-D2-FF-FE-8C-E0-4C
RouterA ipv6 unicast-routing MAC: 00-19-D2-8C-E0-4C 1 NDP Router Solicitation 2 NDP Router Advertisement From: FE80::1 (Link-local address) To: FF02::1 (All-hosts multicast) Prefix: 2001:DB8:AAAA:1:: Prefix-length: /64 EUI-64 3 Prefix: 2001:DB8:AAAA:1:: Prefix-length: /64 EUI-64 Interface ID: 02-19-D2-FF-FE-8C-E0-4C Global Unicast Address: 2001:DB8:AAAA:1:0219:D2FF:FE8C:E04C
RouterA ipv6 unicast-routing MAC: 00-19-D2-8C-E0-4C 1 NDP Router Solicitation 2 NDP Router Advertisement From: FE80::1 (Link-local address) To: FF02::1 (All-hosts multicast) Prefix: 2001:DB8:AAAA:1:: Prefix-length: /64 EUI-64 3 Prefix: 2001:DB8:AAAA:1:: Prefix-length: /64 EUI-64 Interface ID: 02-19-D2-FF-FE-8C-E0-4C Global Unicast Address: 2001:DB8:AAAA:1:0219:D2FF:FE8C:E04C Default Gateway: FE80::1
RouterA ipv6 unicast-routing MAC: 00-19-D2-8C-E0-4C 1 NDP Router Solicitation 2 NDP Router Advertisement From: FE80::1 (Link-local address) To: FF02::1 (All-hosts multicast) Prefix: 2001:DB8:AAAA:1:: Prefix-length: /64 EUI-64 3 Prefix: 2001:DB8:AAAA:1:: Prefix-length: /64 EUI-64 Interface ID: 02-19-D2-FF-FE-8C-E0-4C Global Unicast Address: 2001:DB8:AAAA:1:0219:D2FF:FE8C:E04C Default Gateway: FE80::1 • PC1> ipconfig • IPv6 Address. . . . . . : 2001:DB8:AAAA:1:0219:D2FF:FE8C:E04C • Default Gateway . . . . :fe80::1
Windows and the Interface ID PC1> ipconfig Windows IP Configuration Ethernet adapter Local Area Connection: IPv6 Address. . . . . . . . . : 2001:DB8:AAAA:1:0219:D2FF:FE8C:E04C Link-local IPv6 Address . . . : fe80::50a5:8a35:a5bb:66e1%11 Default Gateway . . . . . . . : fe80::1 • Windows XP and Server 2003 use EUI-64. • Windows Vista and newer do not use EUI-64; hosts create a random 64-bit Interface ID. The %value following the link-local address is a Windows Zone ID and not part of IPv6.
Live Demo Client ipv6 address autoconfig [default] / ipv6ndautoconfig default-route debug ipv6nd show ipv6intbr show ipv6int show ipv6 route See Wireshark capture 1.
M and O bits M means = Managed O means = Other These bits are set in RA ( Router Advertisement) and sent to end devices M=0 and O=0 use SLAAC and use static config for DNS config M=0 and O=1 use SLAAC and use DHCPv6 server for DNS config This is called Stateless DHCP as DHCP server does not maintain any binding M=1 and O=0 use DHCPv6 server to get all the information This is called as Stateful DHCP as the server maintains all the bindings M=1 and O=1 Invalid
RouterA ipv6 unicast-routing DHCPv6 Server DHCPv6 Server Stateless Addressing 1 NDP Router Solicitation NDP Router Advertisement “Here is my information but you need to get other information such as DNS addresses from a DHCPv6 server.” Or “I can’t help you. Ask a DHCPv6 server for all your information.” 2
RouterA ipv6 unicast-routing “Stateless DHCPv6” DHCPv6 Server Address obtained via SLAAC 1 DHCPv6 Solicit Message “I need a DHCPv6 Server.” Not always generated 2 DHCPv6 Advertise Message “I’m a DHCPv6 Server.” 3 DHCPv6 Information Request Message “I need some other information. DHCPv6 Reply Message “Here is your other information.” 4
Live Demo Client ipv6 address autoconfig [default] / ipv6ndautoconfig default-route shipv6dhcpintf0/0 debug dhcp Server ipv6dhcp pool DHCP ipv6nd other-config-flag ipv6dhcp server DHCP shipv6dhcppool debug ipv6dhcp See Wireshark capture 2.
RouterA ipv6 unicast-routing “Stateful DHCPv6” DHCPv6 Server DHCPv6 Addressing 1 DHCPv6 Solicit Message “I need a DHCPv6 Server.” 2 DHCPv6 Advertise Message “I’m a DHCPv6 Server.” 3 DHCPv6 Request Message “I need addressing information. DHCPv6 Reply Message “Here is your address and other information.” 4
Live Demo Client ipv6 address dhcp shipv6dhcpintf0/0 debug dhcp Server ipv6dhcp pool DHCP ipv6ndmanaged-config-flag ipv6dhcp server DHCP shipv6dhcppool debug ipv6dhcp See Wireshark capture 3.
Agenda Global unicast address assignment • Stateless Address Autoconfiguration • Stateless DHCP • StatefulDHCP Other types of addresses • Link Local Address • Multicast Address • Solicited Node Multicast
IPv6 Address Types IPv6 Addressing Unicast Multicast Anycast Assigned Solicited Node FF00::/8 FF02::1:FF00:0000/104 Embedded IPv4 Unspecified Unique Local Global Unicast Link-Local Loopback FC00::/7 FDFF::/7 2000::/3 3FFF::/3 ::1/128 ::/128 ::/80 FE80::/10 FEBF::/10 Note: There are no broadcast addresses in IPv6
Link-Local Unicast IPv6 Addressing Unicast Multicast Anycast Assigned Solicited Node FF00::/8 FF02::1:FF00:0000/104 Embedded IPv4 Unspecified Unique Local Global Unicast Link-Local Loopback FC00::/7 FDFF::/7 2000::/3 3FFF::/3 ::1/128 ::/128 ::/80 FE80::/10 FEBF::/10
Link-local unicast Remaining 54 bits 64 bits 10 bits /64 1111 1110 10xx xxxx Interface ID FE80::/10 EUI-64, Random or Manual Configuration Range: FE80::/10 FEBF::/10
Link-local unicast Remaining 54 bits 64 bits 10 bits /64 1111 1110 10xx xxxx Interface ID FE80::/10 EUI-64, Random or Manual Configuration Range: FE80::/10 FEBF::/10
Link-local unicast Remaining 54 bits 64 bits 10 bits /64 1111 1110 10xx xxxx Interface ID FE80::/10 EUI-64, Random or Manual Configuration • Used to communicate with other devices on the link.
Link-local unicast Remaining 54 bits 64 bits 10 bits /64 1111 1110 10xx xxxx Interface ID FE80::/10 EUI-64, Random or Manual Configuration • Used to communicate with other devices on the link. • Are NOT routable off the link.
Link-local unicast Remaining 54 bits 64 bits 10 bits /64 1111 1110 10xx xxxx Interface ID FE80::/10 EUI-64, Random or Manual Configuration • Used to communicate with other devices on the link. • Are NOT routable off the link. • An IPv6 device must have at least a link-local address.
Link-local unicast Remaining 54 bits 64 bits 10 bits /64 1111 1110 10xx xxxx Interface ID FE80::/10 EUI-64, Random or Manual Configuration • Used to communicate with other devices on the link. • Are NOT routable off the link. • An IPv6 device must have at least a link-local address. • Used by: • A host to communicate on the IPv6 network before it gets a global unicast address.
Link-local unicast Remaining 54 bits 64 bits 10 bits /64 1111 1110 10xx xxxx Interface ID FE80::/10 EUI-64, Random or Manual Configuration • Used to communicate with other devices on the link. • Are NOT routable off the link. • An IPv6 device must have at least a link-local address. • Used by: • A host to communicate on the IPv6 network before it gets a global unicast address. • A host as the default gateway address.
Link-local unicast Remaining 54 bits 64 bits 10 bits /64 1111 1110 10xx xxxx Interface ID FE80::/10 EUI-64, Random or Manual Configuration • Used to communicate with other devices on the link. • Are NOT routable off the link. • An IPv6 device must have at least a link-local address. • Used by: • A host to communicate on the IPv6 network before it gets a global unicast address. • A host as the default gateway address. • Adjacent routers to exchange routing updates.
2001:0DB8:CAFE:A001::/64 Global Unicast: 2001:0DB8:CAFE:1::1/64 R1 R2 Ser 0/0/0 .1 Ser 0/0/0 .2 Fa0/0 Link-local address: ? • Link-local address automatically created when (before) the global unicast address is. 2001:0DB8:CAFE:1::/64 Global Unicast: 2001:0DB8:CAFE:1::0100 PC-1 Link-local address: ?
2001:0DB8:CAFE:A001::/64 Global Unicast: 2001:0DB8:CAFE:1::1/64 R1 R2 Ser 0/0/0 .1 Ser 0/0/0 .2 Fa0/0 Link-local address: ? • Link-local address automatically created when (before) the global unicast address is. • FE80 + 64-bit Interface ID • EUI-64 Format or • Randomly generated 2001:0DB8:CAFE:1::/64 Global Unicast: 2001:0DB8:CAFE:1::0100 PC-1 Link-local address: ?