If the address is generated via EUI-64, it can safely be assumed to be unique. On ethernet, if the MAC isn't unique, there will be other problems. Any self generated address(es) must be verified unique because they could be duplicated.
1 - Many networks were allocated prior to the existence of IANA. There's no method to force the recipients to give them back.
2 - there's no point in doing so. This would slightly delay the total exhaustion of IPv4 but not in any meaningful way.
3 - The future is IPv6, delaying IPv4 exhaustion only delay the point where people are forced to use IPv6. This ...
The full cutover to IPv6 is still far out. Organizations entire infrastructure will need to change to address this. Most of us aren't running IPv6 at all - period - let alone as the main protocol. This will be big $$$.
IPv4 and IPv6 are separate protocols. They can't inter work without some form of translation mechanism.
The original idea of the IPv6 proponents was that we would all move to dual stack running IPv4 and IPv6 in parallel. Then once everything was dual stack, IPv4 could be phased out.
The problem is that plan just isn't attractive from an economic perspective. ...
With UDP, the checksum is optional, but it's mandatory for ICMP.
Accordingly, you do not replace a calculated 0x0000 with 0xffff.
For reference, check RFC 4443 2.3:
2.3. Message Checksum Calculation
The checksum is the 16-bit one's complement of the one's complement
sum of the entire ICMPv6 message, starting with the ICMPv6 message
type field, and prepended ...
Using the UDP checksum is optional for IPv4 (required for IPv6). If the checksum is not used, the checksum is set to all-zeroes. If the checksum is used, and the computed checksum is all-zeroes, the checksum is set to all-ones.
progress seems throttled because companies still want to charge for IPs and don't want to address that there is no IP starvation in IPv6 (yet).
TL/DR: ISPs have a valid reason to charge from IP addressing. The reason behind slow adaptation is money, but profiting of the IP address charges is a tiny minuscule factor in the equation.
As long as there's no ...
An IPv6 address is useless when there's an IPv4-only partner that needs to connect - they are separate protocols and there's no connectivity between them.
Still, IPv4 is the only protocol allowing a server to offer services to everyone - even users with IPv6 primarily still have some IPv4 connectivity (e.g. DS-Lite), but not vice versa. That is only going to ...
IPv4 and IPv6 are two different protocols. They are not interchangeable without a lot of work.
So if you want to talk to v4 devices you run v4. If you want to talk to v6 devices you run v6. Most of the time, you run both.
You are confusing a couple of things. MTU is Maximum Transmission Unit, and it is a value of the data-link (layer-2) protocol on a specific medium.
IP, neither IPv4 nor IPv6 has an MTU. They both have maximum packet sizes, which are much larger than any data-link MTU. The total packet size (header and payload) for an IPv4 packet is 65,535 octets. For IPv6, ...
If you're seeing duplicates with DHCPv4, it's very likely you'd see the same with DHCPv6, because the problem is with your DHCP server and/or configuration. Both systems work exactly the same, addresses generally aren't recycled until they have to be. (when a lease expires, the address becomes a "tombstone" -- expired but still in the database as ...