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I read the article, also found it a bit confusing and wayward, and couldn't quite articulate why I disagreed with it at first, but I think I can now. - The "mo

I read the article, also found it a bit confusing and wayward, and couldn't quite articulate why I disagreed with it at first, but I think I can now. - The "mobile IP" problem isn't IP's job and should not be. IP should be as stateless as possible because this makes it cheap and easy to add capacity and redundancy to a network. - IP addresses are assigned to interfaces, not people, computers, devices, applications, nodes, etc. If you want a fixed reference identifier associated to something across the wire, it is correct to implement that in addition to the state it requires on top of IP. If your application assigns or assumes identity based on IP address, that's a badly written application at this point. > Y has no idea what that means, and throws it away. X should have sent Y a session ID? The client and server should maintain session IDs and not the IP layer (imagine the security issues)? - I think the author mostly has a problem with TCP. QUIC may become the next TCP. And that's fine.

derefr 3y ago
> The "mobile IP" problem isn't IP's job and should not be. IP should be as stateless as possible because this makes it cheap and easy to add capacity and redundancy to a network. But, to be clear, many implementations of IP (both IPv4 and IPv6) do already have "mobile IPs." There's nothing stopping you from having "mobile IPs." They're just complex, and only work when everywhere the IP can move between all exists within a single AS. • You can move between multiple wireless APs in a conference hall, and have a layer-3 address that follows you as you switch network segments and thus acquire new layer-2 addresses (which means that the packets destined to that address are being dynamically re-routed at some upstream switch, as the address assignment changes.) • You can move between cellular antenna and frontend infra (think: WiMax or 5G APs) at different places in a city, while remaining connected to a single cellular backend infra (what you'd think of as a "cell tower") and thus holding a single persistent L3 address.
- Dagger2 3y ago
  You can actually move anywhere with Mobile IPv6. If you move outside your AS, it automatically tunnels your traffic back to your home network with IPsec. There's also a feature called "Correspondent Node" which allows you to send traffic directly rather than tunnelling via your home network. Which kind of makes it sound like IPv6 already has the feature the article thinks it should have had.
- blacklion 3y ago
  > You can move between multiple wireless APs in a conference hall, and have a layer-3 address that follows you as you switch network segments and thus acquire new layer-2 addresses (which means that the packets destined to that address are being dynamically re-routed at some upstream switch, as the address assignment changes.) Is it possible to implement this at home, without paying a lot of money? I've tried it with UniFi AP (with software controller) and no luck :-(
  - derefr 3y ago
    For a house, you probably just want wireless range repeaters/extenders, or mesh APs like these (https://www.wired.com/story/best-mesh-wifi-routers/ https://www.wired.com/story/best-mesh-wifi-routers/). Their key advantage being that the backhaul is wireless — you don't have to wire them back to the switch. If you really want to do an "enterprise" wireless setup, and you want it to be cheap, well... you can buy the relevant equipment (802.11 enterprise wireless APs) used, often in bulk. Sometimes computer recyclers even have them! Make sure you buy the stuff intended for office buildings, though, not the conference-hall open-plenum equipment. The conference-hall stuff is like studio lighting: powerful at a distance (five-storey hall ceiling down to you on the floor) at the expense of guzzling power and dumping tons of heat. Also, obviously, unlike the home stuff, with the enterprise hardware, you do need to be able to run an Ethernet backhaul back to a switch somewhere, to join all these APs' L1 collision-domains into a common link-layer network segment. And that switch has to understand what it's doing, so you'd probably need something enterprise-y there, too, unless the state of open-source consumer router firmware has really caught up with enterprise.
    - blacklion 3y ago
      Extenders works very badly, as they use 1/2 of bandwidth for themselves and need to be placed twice as often as APs. I have no problem to wire normal APs to switch, as I have several RJ45 sockets in each corner of each room :-) Now I have one AP per room already, but can not implement seamless transition - when phone/laptop switches to other AP it requests DHCP again and drops all connections. It is very inconvenient. I know "Buy Cisco's APs for $700/piece and controller for several thousand $$$", I wander why there is no open-source solution (hostapd & Ko), which "secret source" these enterprise solutions include, is it private technology or some open industrial standards, like 802.11[some obscure letter]? Many expensive APs are built with Linux and hostpad inside, and still doesn't support this feature.
lproven 3y ago
> The "mobile IP" problem isn't IP's job and should not be. Not an expert here, but my understanding of the argument is: For constructing virtual networks, which may be distributed across the real Internet, the new protocol needed a virtual translation layer. It doesn't have one. Instead it just had a vastly larger address space, which doesn't help with this.

derefr 3y ago

> The "mobile IP" problem isn't IP's job and should not be. IP should be as stateless as possible because this makes it cheap and easy to add capacity and redundancy to a network. But, to be clear, many implementations of IP (both IPv4 and IPv6) do already have "mobile IPs." There's nothing stopping you from having "mobile IPs." They're just complex, and only work when everywhere the IP can move between all exists within a single AS. • You can move between multiple wireless APs in a conference hall, and have a layer-3 address that follows you as you switch network segments and thus acquire new layer-2 addresses (which means that the packets destined to that address are being dynamically re-routed at some upstream switch, as the address assignment changes.) • You can move between cellular antenna and frontend infra (think: WiMax or 5G APs) at different places in a city, while remaining connected to a single cellular backend infra (what you'd think of as a "cell tower") and thus holding a single persistent L3 address.

Dagger2 3y ago
You can actually move anywhere with Mobile IPv6. If you move outside your AS, it automatically tunnels your traffic back to your home network with IPsec. There's also a feature called "Correspondent Node" which allows you to send traffic directly rather than tunnelling via your home network. Which kind of makes it sound like IPv6 already has the feature the article thinks it should have had.
blacklion 3y ago
> You can move between multiple wireless APs in a conference hall, and have a layer-3 address that follows you as you switch network segments and thus acquire new layer-2 addresses (which means that the packets destined to that address are being dynamically re-routed at some upstream switch, as the address assignment changes.) Is it possible to implement this at home, without paying a lot of money? I've tried it with UniFi AP (with software controller) and no luck :-(
- derefr 3y ago
  For a house, you probably just want wireless range repeaters/extenders, or mesh APs like these (https://www.wired.com/story/best-mesh-wifi-routers/ https://www.wired.com/story/best-mesh-wifi-routers/). Their key advantage being that the backhaul is wireless — you don't have to wire them back to the switch. If you really want to do an "enterprise" wireless setup, and you want it to be cheap, well... you can buy the relevant equipment (802.11 enterprise wireless APs) used, often in bulk. Sometimes computer recyclers even have them! Make sure you buy the stuff intended for office buildings, though, not the conference-hall open-plenum equipment. The conference-hall stuff is like studio lighting: powerful at a distance (five-storey hall ceiling down to you on the floor) at the expense of guzzling power and dumping tons of heat. Also, obviously, unlike the home stuff, with the enterprise hardware, you do need to be able to run an Ethernet backhaul back to a switch somewhere, to join all these APs' L1 collision-domains into a common link-layer network segment. And that switch has to understand what it's doing, so you'd probably need something enterprise-y there, too, unless the state of open-source consumer router firmware has really caught up with enterprise.
  - blacklion 3y ago
    Extenders works very badly, as they use 1/2 of bandwidth for themselves and need to be placed twice as often as APs. I have no problem to wire normal APs to switch, as I have several RJ45 sockets in each corner of each room :-) Now I have one AP per room already, but can not implement seamless transition - when phone/laptop switches to other AP it requests DHCP again and drops all connections. It is very inconvenient. I know "Buy Cisco's APs for $700/piece and controller for several thousand $$$", I wander why there is no open-source solution (hostapd & Ko), which "secret source" these enterprise solutions include, is it private technology or some open industrial standards, like 802.11[some obscure letter]? Many expensive APs are built with Linux and hostpad inside, and still doesn't support this feature.

lproven 3y ago

> The "mobile IP" problem isn't IP's job and should not be. Not an expert here, but my understanding of the argument is: For constructing virtual networks, which may be distributed across the real Internet, the new protocol needed a virtual translation layer. It doesn't have one. Instead it just had a vastly larger address space, which doesn't help with this.