Timeline for Why is localhost IP 127.0.0.1?
Current License: CC BY-SA 3.0
6 events
| when toggle format | what | by | license | comment | |
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| Feb 15 at 20:14 | comment | added | David Storfer | Mikko, it seems like we have endless amounts of resources now, but it's not like assembly language disappeared. Think about the importance of efficiency here. How many data packets do you suppose pass through the internet daily? I don't know what comes after decillion (trillion, quadrillion,... decillion) but I bet the number is a lot higher than that. Doesn't it seem like this little tweak of efficiency is part of the reason the internet is as fast and durable as it is? Take that out and the cost of running the internet to give us the performance we're used to would be unaffordable. | |
| Jan 31, 2023 at 13:25 | comment | added | Mikko Rantalainen | Selecting specific magical binary values for a new protocol because it happened to have the best performance on a single CPU architecture? Yes, it does check the premature optimization box in my books. | |
| Jan 31, 2023 at 0:31 | comment | added | Joseph Bui | A great example of optimization, yes. Premature? No. Read this description of how IPv4 was defined by direct competition in RFC 1025 datatracker.ietf.org/doc/rfc1025 | |
| Jan 26, 2023 at 12:21 | comment | added | Mikko Rantalainen | This is a great example of premature optimization. Compared to all the other latencies needed for network communication, the ability to avoid a single compare operator on a given hardware was pretty poor cause for messing the address space to allocate 16 million addresses to localhost use only, from the middle of possible 32 bit address space. Localhost could have been only 1.1.1.1 just as well. However, that would have prevented Cloudflare from running global DNS service in that IP address later... | |
| Apr 15, 2011 at 15:39 | comment | added | Joseph Bui | Note that I used "words" because old machines back then had unusual word sizes, but they often still used 8 bit arithmetic. For an 8088, I would have said "bytes." | |
| Apr 15, 2011 at 15:36 | history | answered | Joseph Bui | CC BY-SA 3.0 |