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Why do you say that these protocols are worse than Ethernet/IPv4? I'm not intimately familiar with any at L2/L3, but I don't think any have hacks as bad as ARP.

Why do you say that these protocols are worse than Ethernet/IPv4? I'm not intimately familiar with any at L2/L3, but I don't think any have hacks as bad as ARP. (USB does have some weirdness at L1 though I know.)

amluto 4y ago
I’ve generally considered IPv6 neighbor discovery to be a worse hack than ARP. ARP is a straightforward, fairly clean hack to layer the IPv4 addressing scheme over Ethernet, and it doesn’t pollute IPv4 itself. Neighbor discovery layers IPv6 on top of pseudo-IPv6, where the latter operates without knowledge of MAC addresses but nonetheless hardcodes knowledge of Ethernet. But hey, it eliminated the use of Ethernet broadcast in favor of a more complex but functionally identical multicast scheme.
- dooglius 4y ago
  Oh sure, the point is more that Ethernet/IP has to coordinate two separate ID spaces at all, whereas AFAIK no other packet-based protocol like the ones mentioned does this, so in that sense those protocols are better.
bsder 4y ago
> Why do you say that these protocols are worse than Ethernet/IPv4? Here's an example: I connected my nice expensive audio interface to my Thunderbolt port. It worked great! Then I moved a window on my monitor and all hell broke loose. In spite of the fact that it had way more than enough bandwidth to handle everything. See, Thunderbolt doesn't have the ability to say "This tiny packet going to there needs priority and you need to break up those giant display packets." Ethernet has solved problems like these in standards. They're not always implemented on particular chipsets, but they exist, and you generally can buy a product that has them. Everything Ethernet has done and standardized has generally been for a reason. If you don't implement Ethernet, then you are starting over from scratch and will have to reimplement all of that stuff. And you're probably not smarter than the guys who did it for Ethernet. (If I'm being charitable: what's happened is that lot of standards tried to be more cost optimized than Ethernet. The problem is that transistor prices keep coming down. Eventually the price delta between Ethernet and <whatever> becomes inconsequential and you're basically left with real Ethernet and "kinda crappy" Ethernet at almost the same price.)

amluto 4y ago

I’ve generally considered IPv6 neighbor discovery to be a worse hack than ARP. ARP is a straightforward, fairly clean hack to layer the IPv4 addressing scheme over Ethernet, and it doesn’t pollute IPv4 itself. Neighbor discovery layers IPv6 on top of pseudo-IPv6, where the latter operates without knowledge of MAC addresses but nonetheless hardcodes knowledge of Ethernet. But hey, it eliminated the use of Ethernet broadcast in favor of a more complex but functionally identical multicast scheme.

dooglius 4y ago
Oh sure, the point is more that Ethernet/IP has to coordinate two separate ID spaces at all, whereas AFAIK no other packet-based protocol like the ones mentioned does this, so in that sense those protocols are better.

bsder 4y ago

> Why do you say that these protocols are worse than Ethernet/IPv4? Here's an example: I connected my nice expensive audio interface to my Thunderbolt port. It worked great! Then I moved a window on my monitor and all hell broke loose. In spite of the fact that it had way more than enough bandwidth to handle everything. See, Thunderbolt doesn't have the ability to say "This tiny packet going to there needs priority and you need to break up those giant display packets." Ethernet has solved problems like these in standards. They're not always implemented on particular chipsets, but they exist, and you generally can buy a product that has them. Everything Ethernet has done and standardized has generally been for a reason. If you don't implement Ethernet, then you are starting over from scratch and will have to reimplement all of that stuff. And you're probably not smarter than the guys who did it for Ethernet. (If I'm being charitable: what's happened is that lot of standards tried to be more cost optimized than Ethernet. The problem is that transistor prices keep coming down. Eventually the price delta between Ethernet and <whatever> becomes inconsequential and you're basically left with real Ethernet and "kinda crappy" Ethernet at almost the same price.)