5 ms·

Why would they need the same port?

vel0city 2y ago
Because they don't want to have to rely on an external service to find the right port. Just like how your browser doesn't need to be told to connect to :443 for HTTPS. If you're connecting encrypted SIP, the port is assumed to be 5061. Just like HTTP is assumed to be 80, SSH is 22, etc.
- Hikikomori 2y ago
  But the external service needs to know your ip, so why not port as well?
  - vel0city 2y ago
    Did you have to look up something to know this site is hosted on :443 or did you just make an assumption? Some kind of standardized port you connected on? Wouldn't it be nice if every device could just assume the standardized ports were available for them if they wanted them?
    - Hikikomori 2y ago
      VOIP systems don't really work like random webservers though.
      - vel0city 2y ago
        There's little reason why they couldn't though. Why shouldn't I just call Apple by doing sip://support.apple.com ? Why can't people just call me at sip://desk-phone.vel0city.whatever (they actually can, if they know the right name) or sip://cell.hikikomori.apple.net ? Instead, we're locked into proprietary platforms or relying on old phone systems.
        ninkendo 2y ago
        Ok so try calling my phone at sip://ninkendo.example. Oh, I’m actually not at my house. I’m traveling and my device is moving from one cell tower to the next, getting a new IP address every few minutes. Then I get to my friends house and his router is gonna block unestablished connections so you better call me soon. No, there’s a reason software like FaceTime, and calling in general, are mediated by centralized services and implemented as client-server. Because relying on your users to have stable IP’s, and to always be behind a properly configured firewall, would be an utterly insane way to design something. Hence “ipv6 is a relic of a bygone era”, because in the era we live in now, IP addresses change and users move between networks constantly, and NAT is very much the least of our problems.
        vel0city 2y ago
        > my device is moving from one cell tower to the next, getting a new IP address every few minutes You're pretty much never getting a new IP at every cell tower. > Then I get to my friends house and his router is gonna block unestablished connections so you better call me soon. PMP can solve that. > Because relying on your users to have stable IP’s Not a stable IP, but some kind of stable identity. Like a DNS name. That can be provided by someone like Apple, or Google, or whoever. It doesn't need to be ultra-centralized by only a single thing controlling it.
        ninkendo 2y ago
        [flagged]
        vel0city 2y ago
        > I don’t think I’ve met someone that truly thinks technological progress stopped in the 1990s and that URL’s and DNS are all we actually need I never said this. You're putting some rather strong words in my mouth. Just giving an example of something that could have been if it wasn't for NAT and an acceptance that you need a third party platform to allow you talk. Feel free to change out the pieces to whatever. Personally I'd like to be able to just dial a FaceTime-like client from any device instead of just what Apple blesses with accounts Apple allows. And have that stack just be the norm. I understand NAT isn't the only headache that prevents this, but it is one of the several that does. I don't think it's crazy to think easy dynamic DNS services could have become common if advertised right. People don't know how phone numbers work but in the end they know how to use them. The tech for routers to auto configure firewall rules based on client requests exists, and potentially if everyone-has-a-public-ip was common we'd have seen less reliance on brittle edge firewalls and NAT to provide so much of our security. Killing NAT doesn't solve all the problems, but it does solve some of them. And I'd prefer solving the ones that help give users more freedom instead of accepting things like CGNAT.
  - Tigress8780 2y ago
    We have this thing called NATMap: https://github.com/heiher/natmap https://github.com/heiher/natmap It gives you a public dynamic IP + port combination if your network is NAT1 all the way to the internet. Both IP & port being dynamic kinda complicates things, they ended up inventing a new DNS record type, "IP4P" where IPv4 address and port are encoded as an IPv6 address, and modified WireGuard/OpenVPN clients are required. We are supposed to solve this using SRV records, but I don't think many consumer-facing apps can do this.
- ninkendo 2y ago
  In what world do you not need to rely on an external service to find information like this? IP addresses change, people move around, etc etc. The topic of discussion right now is peer-to-peer software, which is the quintessential thing that is always lauded by ipv6 proponents as the killer app of ipv6, because each device has its own globally-routable IP. But “what address do I send these packets to?” is like, 10% of the issue with designing p2p software. Users ip’s are always changing. They move around. They go behind firewalls that will block their traffic. They go behind firewalls they don’t have permission to reconfigure. This is the case in IPv4, and it will always continue to be the case even if we were 100% IPv6. IPv4 can work today for p2p use cases if you don’t make the assumption that the port is static. But that’s like 1 of N assumptions you have to check if you’re writing peer to peer software. The other N of them are all still issues, even in IPv6.
  - vel0city 2y ago
    > But “what address do I send these packets to?” is like, 10% of the issue with designing p2p software So wouldn't it be nice to go ahead and solve that 10% of the problem instead of just limping along with it?
    - Dylan16807 2y ago
      I hope you're not implying that IPv6 solves the problem of knowing what address to connect to. If you can avoid an explicit port, that can be nice. But anywhere you're using an IP, v6 without a port is longer than v4 with a port. An implicit port is only useful when you're using DNS. (And if you're designing a service, you can choose to use DNS records that contain the port.)
      - vel0city 2y ago
        I'm all for things to start using SRV records as well!

Because they don't want to have to rely on an external service to find the right port. Just like how your browser doesn't need to be told to connect to :443 for HTTPS. If you're connecting encrypted SIP, the port is assumed to be 5061. Just like HTTP is assumed to be 80, SSH is 22, etc.

Hikikomori 2y ago
But the external service needs to know your ip, so why not port as well?
- vel0city 2y ago
  Did you have to look up something to know this site is hosted on :443 or did you just make an assumption? Some kind of standardized port you connected on? Wouldn't it be nice if every device could just assume the standardized ports were available for them if they wanted them?
  - Hikikomori 2y ago
    VOIP systems don't really work like random webservers though.
    - vel0city 2y ago
      There's little reason why they couldn't though. Why shouldn't I just call Apple by doing sip://support.apple.com ? Why can't people just call me at sip://desk-phone.vel0city.whatever (they actually can, if they know the right name) or sip://cell.hikikomori.apple.net ? Instead, we're locked into proprietary platforms or relying on old phone systems.
      - ninkendo 2y ago
        Ok so try calling my phone at sip://ninkendo.example. Oh, I’m actually not at my house. I’m traveling and my device is moving from one cell tower to the next, getting a new IP address every few minutes. Then I get to my friends house and his router is gonna block unestablished connections so you better call me soon. No, there’s a reason software like FaceTime, and calling in general, are mediated by centralized services and implemented as client-server. Because relying on your users to have stable IP’s, and to always be behind a properly configured firewall, would be an utterly insane way to design something. Hence “ipv6 is a relic of a bygone era”, because in the era we live in now, IP addresses change and users move between networks constantly, and NAT is very much the least of our problems.
        vel0city 2y ago
        > my device is moving from one cell tower to the next, getting a new IP address every few minutes You're pretty much never getting a new IP at every cell tower. > Then I get to my friends house and his router is gonna block unestablished connections so you better call me soon. PMP can solve that. > Because relying on your users to have stable IP’s Not a stable IP, but some kind of stable identity. Like a DNS name. That can be provided by someone like Apple, or Google, or whoever. It doesn't need to be ultra-centralized by only a single thing controlling it.
        ninkendo 2y ago
        [flagged]
        vel0city 2y ago
        > I don’t think I’ve met someone that truly thinks technological progress stopped in the 1990s and that URL’s and DNS are all we actually need I never said this. You're putting some rather strong words in my mouth. Just giving an example of something that could have been if it wasn't for NAT and an acceptance that you need a third party platform to allow you talk. Feel free to change out the pieces to whatever. Personally I'd like to be able to just dial a FaceTime-like client from any device instead of just what Apple blesses with accounts Apple allows. And have that stack just be the norm. I understand NAT isn't the only headache that prevents this, but it is one of the several that does. I don't think it's crazy to think easy dynamic DNS services could have become common if advertised right. People don't know how phone numbers work but in the end they know how to use them. The tech for routers to auto configure firewall rules based on client requests exists, and potentially if everyone-has-a-public-ip was common we'd have seen less reliance on brittle edge firewalls and NAT to provide so much of our security. Killing NAT doesn't solve all the problems, but it does solve some of them. And I'd prefer solving the ones that help give users more freedom instead of accepting things like CGNAT.
- Tigress8780 2y ago
  We have this thing called NATMap: https://github.com/heiher/natmap https://github.com/heiher/natmap It gives you a public dynamic IP + port combination if your network is NAT1 all the way to the internet. Both IP & port being dynamic kinda complicates things, they ended up inventing a new DNS record type, "IP4P" where IPv4 address and port are encoded as an IPv6 address, and modified WireGuard/OpenVPN clients are required. We are supposed to solve this using SRV records, but I don't think many consumer-facing apps can do this.
ninkendo 2y ago
In what world do you not need to rely on an external service to find information like this? IP addresses change, people move around, etc etc. The topic of discussion right now is peer-to-peer software, which is the quintessential thing that is always lauded by ipv6 proponents as the killer app of ipv6, because each device has its own globally-routable IP. But “what address do I send these packets to?” is like, 10% of the issue with designing p2p software. Users ip’s are always changing. They move around. They go behind firewalls that will block their traffic. They go behind firewalls they don’t have permission to reconfigure. This is the case in IPv4, and it will always continue to be the case even if we were 100% IPv6. IPv4 can work today for p2p use cases if you don’t make the assumption that the port is static. But that’s like 1 of N assumptions you have to check if you’re writing peer to peer software. The other N of them are all still issues, even in IPv6.
- vel0city 2y ago
  > But “what address do I send these packets to?” is like, 10% of the issue with designing p2p software So wouldn't it be nice to go ahead and solve that 10% of the problem instead of just limping along with it?
  - Dylan16807 2y ago
    I hope you're not implying that IPv6 solves the problem of knowing what address to connect to. If you can avoid an explicit port, that can be nice. But anywhere you're using an IP, v6 without a port is longer than v4 with a port. An implicit port is only useful when you're using DNS. (And if you're designing a service, you can choose to use DNS records that contain the port.)
    - vel0city 2y ago
      I'm all for things to start using SRV records as well!