Note that you can use https://ipmap.ripe.net to lookup any IP address and RIPE Atlas measurements will be scheduled in the background to figure out the the location. So no need to schedule measurements manually (requiring credits).
We're also working on a reverse DNS geolocating backend BTW. We will look into this paper.
You need NAT whenever you can't change your peers' routing table, for whatever reason.
It's used extensively in IPv4 world for LAN=>WAN connectivity because your only peer (your ISP) won't agree to send all traffic for 192.168.0.0/24 to your home.
Its most popular use case disappearing doesn't make it any less useful for the narrow set of circumstances when it's basically your only option.
NAT64 is NAT in reverse, essentially. Your internal, IPv6 network can use it to contact an IPv4 host by embedding the target address. This is arguably better than current NAT44. The NAT64 only needs to track which ports and IPs are used on the IPv4 side which should become easier as more hosts don't require an IPv4 anymore.
It's a last-stage transitional method IMO, when most but not all of the internet is IPv6.
Using ping is a really crude way of establishing the 'darkness' of a prefix.
Complete prefixes just block off all ICMP incoming traffic, as do many core internet infra-structural devices (although they may pass them on, they won't answer pings directed to them).
lat,lon doesn't have any precision attached to it. Also, you might be surprised how many times people get them reversed. Hey, even geojson encodes it as lon,lat.
Also easily normalizing (lat,lon)s isn't so straight forward.
And then there's subtleties when people are actually not using the WGS84 but a crs/datum one shifted a few tens of miles.
Sort of surprised that nobody compares this to geohash[0], though.
I hope that Google will be throwing its weight behind it (seems so for now) and proposes a rfc for this so we can stop bikeshedding about geo encoding standards.
Geohash is a great idea, but at the end of the day all these systems are a mapping to latitude,longitude. The lat,lon precision can be derived from the number of digits after the decimal point.
The main argument for the existence of these systems is that lat,lon is hard to remember. Here is a simple solution, convert any lat,lon pair to an easier to remember pair (ie a pair where numbers are repetitive, consecutive, etc).
for eg: 45.89988,-64.36288 -> 45.9,-64.363
and so on. It is a simple hack making ll memorable without sacrificing much accuracy.
I agree with the bike shedding comment! It seems to me that the location format is the most trivial part of an addressing infrastructure. Any system could easily be successful, but it needs a level of infrastructure and support to work which is not trivial. My guess is that the eventual solution will be for apps to use GPS and camera to identify delivery points in places that lack good addresss infrastructure.
> Having “intrinsic motivations”, sometimes a true passion, for what the social service worker does is the best prerequisite to have a satisfactory relation with clients.
This. Doesn't this hold for so many professions or just so many things we do in life?
What an excellent interview and what good to see such a positive insight on (a part) of Italy's economy. In the aftermath of the financial crisis in 2008 a lot of Italy bashing (together with basically all Southern European EU countries) has been going on, most of it completely based on stereotypes.
Also makes me wonder if cooperations like these are one of the reasons why (Northern) Italian design is so damn good.
Italian design is a result of a 2000-year-old legacy of excellence in art and, sadly, has nothing to do with cooperation. The famous names (Bertone, Pininfarina, Ferrari etc) have always been regular companies, and Emilia is not really a traditional center of design activity - for that you would look at Milan, Rome, and Turin. You do have the DAMS in Bologna, aka "Umberto Eco's faculty", but it's always been more about media than design.
The somewhat-distributed coop model traditionally helped and incentivised STEM-oriented schools. Emilia has some of the best engineering schools in the country, both at university level and below, and a huge network of engineering-based companies working in industrial automation and precision instruments - including the Motor Valley of Ferrari-Lamborghini-Ducati fame. Even there, you really remember the cars designed by Bertone and Pininfarina, studios based further North.
Nice manual. Good to see that they show the raw sockets api and libraries using them side by side. Skimming through it though, it a eems a bit thin on ipv6 details, e.g. recvmsg is not mentioned, but is indispensable for receiving ancillary data from ipv6 icmp packets.
Skimming it, unless I missed it, under Linux there is no mention of epoll, edge vs level triggering. Things you should familiarize yourself with if you care about performance.
We're also working on a reverse DNS geolocating backend BTW. We will look into this paper.