61–70 of 108 posts
I wonder if ping could be abused to send short messages for p2p networking over UDP without a central server to handle NAT busting. Looks like someone figured the message part out: https://stackoverflow.com/questions/31857419/how-to-send-a-m... Unfortunately ping is handled by the OS so apps on the peer IPs wouldn't be able to read the messages. I wonder if it's time to provide hooks to some of these services in user…
(from top comment)
Earlier quoted context omitted.
With IPv6 you would do stateless autoconfigurarion, so there would be no manually setting of your addresses. The router would advertise the new prefix and everything would just use it. There would be no DNS configuration at all, all local machines would use anycast DNS for the services and a well known server for Internet addresses. One of the primary goals of IPv6 was to avoid needing manual configuration if anythin…
> There would be no DNS configuration at all, all local machines would use anycast DNS for the services and a well known server for Internet addresses. Assumptions and dragons be here.
Earlier quoted context omitted.
I have a few devices on my home internet, on a handful of 192.168 subnets The other week I moved my ISP. The AS my house belonged to obviously changed to the new ISP, and I got a new v4 IP All I had to do was update my Wan router to forward trafffic from the new Ip. Instead with ipv6 I would have to change every node on my network, update my internal DNS. Now in theory I could have my own /48 which I take with me. Th…
With IPv6 you would do stateless autoconfigurarion, so there would be no manually setting of your addresses. The router would advertise the new prefix and everything would just use it. There would be no DNS configuration at all, all local machines would use anycast DNS for the services and a well known server for Internet addresses. One of the primary goals of IPv6 was to avoid needing manual configuration if anythin…
Earlier quoted context omitted.
I have a few devices on my home internet, on a handful of 192.168 subnets The other week I moved my ISP. The AS my house belonged to obviously changed to the new ISP, and I got a new v4 IP All I had to do was update my Wan router to forward trafffic from the new Ip. Instead with ipv6 I would have to change every node on my network, update my internal DNS. Now in theory I could have my own /48 which I take with me. Th…
I do believe there is some kind of 1:1 NAT with IPv6 these days, which is way better than 1:Many of IPv4. There are so many potentially useful applications that are DOA because of v4 NAT being everywhere.
When a ping is sent from a device on a local network to a device on the internet, the router performing NAT rewrites the source address of the ping to its public IP address and rewrites the ID field of the ICMP packet to a unique value. When the response is received, the router uses the unique ID value to forward the response to the correct device on the local network.
Taking this thought just a tiny bit further, this is changing a stateless protocol to a stateful one.
NAT is such a trashy abstraction. IPv4 needs to die.
Earlier quoted context omitted.
It's super confusing because you can use udp to read icmp packets (but not send, iirc), and i might be wrong, but i remember seeing tuts that did this!!
Getting downvoted, so: https://stackoverflow.com/questions/13087097/how-to-get-icmp... Using a udp socket is the "classic" way of implementing ping on low privilege syystems
NAT is such a trashy abstraction. IPv4 needs to die.
Not sure IPv6 will fix this. Technically, yes it does. But major providers only assigning a /64 to a home user (and charging hefty fees for "buisness use" /48) already leads to IPv6 NAT or segmenting the /64 further - which shoulnt be done.
Earlier quoted context omitted.
Note that blanket dropping of ICMP will break Path MTU Discovery (PMTUD) so you had better not be tunneling or encapsulating TCP traffic.
Actually, ICMP-based PMTUD is almost dead in IPv4 due to this exact problem (since ICMP isn't a "protected" protocol which is required for IPv4 connectivity), most actual services tend to do the MTU discovery purely using UDP or even using TCP ( https://datatracker.ietf.org/doc/html/rfc4821 )
Earlier quoted context omitted.
> There would be no DNS configuration at all, all local machines would use anycast DNS for the services and a well known server for Internet addresses. Assumptions and dragons be here.
MDNS, specifically designed for use on a single vlan, so useless