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