Yes on the same computer. Pretty much every multicast-capable host has a unicast address and has multicast groups that they join when they get an IP address. [0] Edge routers almost always have -at minimum- a global address and a "site-local" address. Any host that has multiple active interfaces can have multiple "categories" of addresses assigned to it.
You might also be unaware of the fact that network interfaces can usually be assigned multiple IPv4 addresses, just like they can be assigned multiple IPv6 addresses.
> ...the application does not have to figure out which one it has to use.
You might be surprised to learn that that's the job of the routing table on the system. Applications can influence the choices made by the system by binding to a specific source address, but the default behavior used by nearly everything is to let the system handle all that for you.
[0] You appear to be unaware that multicast addresses aren't assigned to a host. I suspect you're unaware that IPv6 removed the special-case "broadcast" address. It's now treated as what it actually is; the "all hosts" multicast address.
* (S|D)NAT are not first class citizen in IPV6 Standards and Implementation
* there's no mapping of the IPv4 Adresspace into the v6 space, so people can reroute stuff which is needed.
because only then, we can
a) migrate
b) rebuild the same structures.
> as long as [...] (S|D)NAT are not first class citizen in IPV6 Standards and Implementation
Yeah, I mostly agree... IMO, a ULA (equivalent to RFC1918, so 192.168.x.x and so forth) is the only sane way to set up your IPv6 network at home, unless you're one of the wizards who owns their own prefix. Dynamic prefix delegation just breaks too many things when the prefix changes, and I really wish NPTv6 was more supported and ubiquitous, because it solves the problem in the most elegant way IMO.
> there's no mapping of the IPv4 Adresspace into the v6 space
You don't need NPTv6 to use ULA. Just use both ULA and the dynamic prefix from your ISP. The latter is handled automatically by DHCPv6-PD, and if you're only using it for outbound connections then it changing isn't going to break anything.
I'd say this is actually elegant, compared to NPTv6 which is a kludge and will break things (and isn't well-supported anyway).
I definitely do both ULA and GUA at home, but this only really works well to the degree that the OS will prefer the ULA when connecting to things. Like if I want to put hostnames in netgroups, I need reverse DNS to work (which only works if the client is using the ULA address I expect.) In fact the whole idea of reverse lookups working and having expected hostnames show up where you want them to (logs, etc) really depends on not only using ULA for connections, but using the stable address and not the privacy address, which can also cause issues.
For the most part it works today, if I stick to using ULA’s only in my zone file, and configure hosts to prefer the DHCPv6-provided ULA for connections in the ULA subnet, it’s fine. But suddenly if you connect to somehost.local instead of somehost.fqdn, the machine picks a GUA source address and you’re back to being unpredictable.
So although I say I want to use NPTv6 and be ULA-only, I don’t actually do that today, so I’m not super familiar with the downsides to the approach. But it does sound a lot cleaner to me in theory.
> if you're only using it for outbound connections then it changing isn't going to break anything.
A prefix change absolutely does break things in a lot of setups though. It happens something like:
- Your router reboots unexpectedly (no time to rescind the RA)
- Router comes up and gets a new prefix, starts advertising it
- Clients are brain dead and continue using the old prefix when making outbound connections.
I’ve had this happen and both Apple devices and Linux devices (I had no Windows machines) kept using the old prefix until I went around and rebooted them. So connecting to any IPv6 WAN address would fail, and only IPv4 was saving me from my internet being down until I went and manually rebooted everything.
There have since been RFC’s that come up with recommendations for routers to keep a stateful log of old prefixes, so that they can rescind them (advertise a zero TTL) when a new prefix arrives… but afaict none of them actually do this.
We need a keyring at a company. Because there's no other media for communicating, where you reach management and technical people in companies as well.
And we have massive issues due to the fact that the ongoing-decrying of "shut everything off" and the following non-improvement-without-an-alternative because we have to talk with people of other organizations (and every organization runs their own mailserver) and the only really common way of communication is Mail.
And when everyone has a GPG Key, you get.. what? an keyring.
You could say, we do not need gpg, because we control the mailserver, but what if a mailserver is compromised and the mails are still in mailboxes?
the public keys are not that public, only known to the contenders, still, it's an issue and we have a keyring
You need a private PKI, not keyring. They're subtly different - a PKI can handle key rotation, etc.
Yes there aren't a lot of good options for that. If you're using something like a Microsoft software stack with active directory or similar identity/account management then there's usually some PKI support in there to anchor to.
Across organisations, there's really very very few good solutions. GPG specifically is much too insecure when you need to receive messages from untrusted senders. There's basically S/MIME which have comparable security issues, then we have AD federation or Matrix.org with a server per org.
> You could say, we do not need gpg, because we control the mailserver, but what if a mailserver is compromised and the mails are still in mailboxes?
How are you handling the keys? This is only true if user's protect their own keypairs with strong passwords / yubikey applet, etc.
Okay, that's it. i think i will do some data analysis and do a talk at some place next year about the outcome of the analysis which talks are there and if there's really a trend. :D
The user had more arguments than just "it's all politics". What level of scrutiny does his statement have to hold up to? Because as far as I am concerned this is not here to find scientific truths.
I don't know man. It's always the same debate: It's either "too much politics" or
"no change at all" whenever this issue comes up and the "nothing changed" crowd keeps on reminding everyone that C3 "was always like that". I'm not requesting a scientific study but if you're this convinced that nothing changed despite may old school attendees chiming in to confirm the opposite, perhaps it would be helpful to compare old and new schedules.
I find it strange you didn't latch on to the original comment, which has the exact same problem you complained about, but reacted to the response. The best action is to ignore threads and sub-threads you don't care about and leave others who do to their fun.
reply