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On 7/31/20 12:38 PM, Grant Taylor wrote: |
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> On 7/30/20 3:05 AM, antlists wrote: |
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>> From what little I understand, IPv6 *enforces* CIDR. |
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> |
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> Are you talking about the lack of defined classes of network; A, B, C, |
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> D, E?? Or are you talking about hierarchical routing? |
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> |
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> There is no concept of a class of network in IPv6. |
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> |
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> Hierarchical routing is a laudable goal, but it failed 15-20 years ago. |
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> |
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>> Each customer is then given one of these 64-bit address spaces for |
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>> their local network. So routing tables suddenly become extremely |
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>> simple - eactly the way IPv4 was intended to be. |
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> |
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> Except that things didn't work out that way. |
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> |
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> Provider Independent addresses, multi-homing, and redundant routes mean |
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> that hierarchical routing failed 15-20 years ago. |
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> |
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> Many providers try to address things so that hierarchical routing is a |
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> thing within their network.? But the reality of inter-networking between |
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> providers means that things aren't as neat and tidy as this on the |
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> Internet. |
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> |
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>> This may then mean that dynDNS is part of (needs to be) the IPv6 spec, |
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>> because every time a client roams between networks, its IPv6 address |
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>> HAS to change. |
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> |
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> Nope. |
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> |
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> It's entirely possible to have clients roam between IPv6 (and IPv4) |
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> networks without (one of) it's address(es) changing.? Mobile IP.? VPNs. |
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> Tunnels.? BGP.... |
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> |
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> Sure, the connection to the network changes as it moves from network to |
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> network.? But this doesn't mean that the actual IP address that's used |
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> by the system to communicate with the world changes. |
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> |
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> Take a look at IPv6 Provider Delegation.? At least as Comcast does it, |
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> means that you only have a link-local IPv6 address on the outside and a |
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> /56 on the inside of a network.? The world sees the globally routed IPv6 |
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> network on the inside and doesn't give 2? what the outside link-net IPv6 |
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> address is.? Comcast routes the /56 they delegate to you via the |
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> non-globally-routed IPv6 link-net IPv6 address. |
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> |
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> There are multiple ways to keep the same IP while changing the |
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> connecting link. |
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I'd like to start with a basic list/brief description of these, please? |
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|
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James |
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