81 lines
1.7 KiB
Plaintext
81 lines
1.7 KiB
Plaintext
IPv6
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1. Network layers and IP
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2. Routing and subnets
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3. Problems with IPv4
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4. Solutions of IPv6
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5. SLAAC
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6. IPv4 in IPv6
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Under:
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Link-layer, MAC (Ethernet, Wi-Fi)
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Intra-network communication
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Upper:
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Transport-layer, TCP / UDP
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Data communication
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Middle:
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Internet layer, IPv4/6
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Inter-network communication
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2. Routing and subnets
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CIDR notation:
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192.168.0.0/24 - 192.168.0.XX
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2a0d:d9c0:1234:abcd:5678:cdef:1234:4567/64
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2a0d:d9c0:1234:abcd:xxxx:xxxx:xxxx:xxxx
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192.168.0.0/24 to 192.168.1.0/24
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2a0d:d9c0::/64 to 2a0d:d9c1::/64
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3. Problems with IPv4
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Not enough (public) addresses!
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Private subnets allow extension through NAT
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192.168.0.0/16 behind 45.134.135.1
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Problems: state, complexity...
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And *still* not enough addresses!
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4. Solutions of IPv6
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Many, many, *many* more addresses
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Every device has an address, no NAT
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Enough for everyone.
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(security: NAT does not provide security.
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Proper firewalling does.)
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Otherwise, nothing basic really changes
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Devices have an IPv6, talk to others over link-layer
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Same difference!
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5. SLAAC
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StateLess Address AutoConfiguration
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Usually, in IPv4, DHCP
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Requires manual configuration
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In IPv6, equivalent is SLAAC
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* MAC addresses to autoconfigure address in a subnet
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* Device Address Duplication built-in checks
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* More work for the routers
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Router Advertisements, Router Solicitation
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Neighbor Advertisements, Neighbor Solicitation
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2a0d:d9c0:1234:5678::/64 + MAC address =>
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2a0d:d9c0:1234:5678:224:81ff:fe7d:da46
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6. IPv4 in IPv6
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Same technique as SLAAC: encode IPv4 in IPv6 /64
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2a0d:d9c0:1234:5678:192.168.42.42
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We can use a translation service to provide IPv4 connectivity to IPv6 hosts.
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NAT-like: IPv6 can initiate to IPv4, not the other way around.
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