Tag Info

Hot answers tagged

29

Yes, it does matter. We run a .com.au SaaS application, and latency is quite important. It is physically impossible to get information from the United States to Australia in under 200ms, but we have a typical latency of 20-50ms from our datacenter in North Sydney to most of the east coast on Australia. Yes, it's expensive to lease servers and datacenter ...


13

Does it generally stand to reason that the nearer IP address A is to IP address B numerically, then the nearer IP address A is to IP address B geographically? Most definitely not. IP Netblocks are handed out by IANA to the Regional Internet Registries (RIRs), who in turn hand out netblocks to individual organizations in their region. Once ...


9

As far as off-the-shelf solutions go, many commercial 802.11 networking infrastructures support triangulation of both host computers and "rogue" APs by comparing the signal strength of the source among all the APs that can see the signal. I've used trapeze wireless systems that import autocad maps that include things like building materials (to compensate ...


8

Wikipedia uses the free (as in free speech, not only as in free beer) software PowerDNS to do so, with a geoip backend. Just remember that all the GeoIP databases are imperfect and that geographical location is a poor tool to estimate the network distance to a given server. Protocols like ICS are a much better solution.


7

I'm pretty sure there's no way you can do this with full effectiveness. Even if you do find a way to restrict based on IP or provider, I can still go through a proxy server in an "allowed" location to get the file.


7

You can do some basic Radio Direction Finding to locate the signal. At 2.4 GHz it is easy to come across antennas with small beamwidths. Sweeping one around while watching the signal strength should give you a good idea of what direction the AP is in. Do that from a few physically separated locations and you will have the beginnings of a triangulation. It ...


7

A DNS name may have multiple A records, clients may then choose any record and use that address. That's not the entire truth though, Google's DNS servers are also giving you different A records depending on your IP address so that you may use a server close to you.


7

Google has documented their methods at least partially in their paper Moving Beyond End-to-End Path Information to Optimize CDN Performance. It is largely based on latency to various ASes according to this paper.


6

There are patches available to do GeoIP in various DNS servers. Bind: http://www.caraytech.com/geodns/ Good writeup of Bind patches, includes RPMs: http://www.devco.net/archives/2006/07/11/location%5Faware%5Fbind.php djbdns: http://www.anders.com/cms/276/tinydns.GeoIP.patch/djbdns/Geographically.Aware Also interesting is this hack, which involves not ...


5

They get reassigned very, very rarely, if at all. But have you considered that MaxMind's data may actually be improving over time? I don't think that they currently have enough data to assign a region to each given IP address and if they could, there'd still be some room for improvement by making the regions smaller and smaller. Thus, I think, it all ...


5

There's a free MaxMind GeoIP database, which I think is queryable online (or you can download the database and query against it). They also sell a more accurate database (as do other companies, I'm sure, but that's the one I know about).


5

Yeah, give up on unrealistic ideas. YOu dont know because noone knows. And the data can change (dynamic ip addresses asigned tio dial i ncustomers - where do THEY reside?). Only google knows how their internal network is exactly steructured. What you see is the registered address for the block.


5

A.B.C.001 and A.B.C.002 are very likely to be in close physical proximity, possibly as likely as 99% that they are on the same city block. A.B.C.001 and A.B.C.254 are only slightly less likely to be so. A.B.001.D and A.B.002.D are less likely still, perhaps 90%, for a 256x as large definition of "close". A.B.001.D and A.B.254.D slightly less likey again. ...


5

Do what international shipping companies do and have a "select your country" thing on the front page. Use the browser field to determine the default language. Use geo_ip to determine the default country. Make the user confirm, make sure they can change it, and make sure you store it in a cookie so they don't have to do it again.


4

I believe there'll be 50% chance that DNS resolution for the first load would be a bit faster. After that it will be cached in user's dns servers (usually hosted by ISP), later dns lookups will use the cache (of course if you have adequate TTL). So, I don't think anyone will notice it. But having two dns servers in very different geo locations is very good ...


4

I believe it's called CDN


4

Google uses anycast to route DNS traffic to the closest server farm.


4

Your experiencing issues with google's GEO IP tool; you can fix this by going here where you can register your companies IP block with them and they'll fix it.


4

I'm not sure you can do much better than this XKCD comic. More usefully, there are sites like this one that will tell you the location of some IP addresses, although this and the link I had a few minutes ago don't seem to do that well on my test addresses.


4

By itself, there is no way to get that information from a wifi signal. Google, however, has indexed wifi access points with their locations. So they are able to tell where you are based on the wifi AP you are connected to. In a case like that, it is possible to get a location based on wifi. ...


4

One option is to use geolocation in the browser. Not many devices support it however. Ultimately, GeoIP is an unreliable hack.


4

It should be fairly straightforward in Perl. Just take auth.log and get a list of IPs out of it with grep or awk, then pipe your list of IPs into a Perl script, and use Geo::IP to get a country/city match from it.


3

Ubuntu PreReqs: sudo apt-get install libgeoip1 libgeo-ip-perl libregexp-common-perl Script By Me just For you: #Parses out ip and prints ip followed by country use strict; use warnings; use Regexp::Common qw /net/; use Geo::IP; my $gi = Geo::IP->new(GEOIP_STANDARD); while (<>) { #Following matches IPv4 addresses and stores the result in $1 ...


3

For Europe Amazon EC2 is what you're looking for. There's an option to create a Windows virtual machine in Europe for $0.13 per hour. Create one, run your test, destroy it. Pay only for what you use.


3

If you're looking for a IP GeoLocation database you can download one for free from MaxMind. They also offer a non-free version with higher accuracy (though the free one is good enough for most uses). There are several services out there that are free as well. I suspect Google has their own database and does not rely on an external company to provide the ...


3

You'll have to read more about Geolocation Software and their different types of data gathering techniques. Most online services aimed at geolocation do a regional internet registry lookup, in the U.S. it would be ARIN. There are various types of techniques and accuracy in finding out an actual location, some even combine methods in order to give you their ...


3

You know, not only does numeric "closeness" not have any direct relation on geographical closeness, with the widespread use of NAT there's not even any guarantee that requests from the SAME IP have any geographic relation to each other, in terms of the geographic location of the end user or machine making the request. There are plenty of corporate networks ...


3

End users don't (typically) connect to your authoritative servers. Users connect to recursive servers, which may use algorithms based on round-trip-time (RTT) to choose which authoritative servers to talk to in order to resolve your domain.


3

I'll just try to expand Alnitak's answer. As Alnitak mentioned, end-users normally don't connect to your servers, instead users normally connect to their ISP or other public caching/recursive DNS servers (like google 8.8.8.8), which in turn connect to your authoritative servers. Thus user which located say in Russia, but uses US-based recursive servers, ...



Only top voted, non community-wiki answers of a minimum length are eligible