I really dont think it's easy to limit bandwidth usage ONLY for
Earth Google without making bad experiencies on doing searchs on Google.
No matter if searches are low-bandwidth. If you get some QoS and band
limitation on google IPs, be sure that your google earth users will use
ALL the available bandwidth, thus making google earth as well as google
serching probably extremely slow.
I'm actually making some limitations on Google Earth on the HTTP
proxy, squid. Several of them are running transparent. User doesnt need
to configure it on the browser. In some cases, I have squid running
without caching and without logging. They are running JUST for limiting
that !!!!
On the actual version, software Google Earth seems to get
information using HTTP. I just get this from my squid log file:
Sat Aug 13 10:59:51 2005 949 192.168.1.50 TCP_MISS/200 15300 GET
http://kh.google.com/flatfile?f1-0023212010203-i.4 -
DIRECT/64.233.179.93 application/octet-stream
Sat Aug 13 10:59:53 2005 1979 192.168.1.50 TCP_MISS/200 2631 GET
http://kh.google.com/flatfile?f1c-0023212010331-t.1 -
DIRECT/64.233.179.93 application/octet-stream
Sat Aug 13 10:59:53 2005 4464 192.168.1.50 TCP_MISS/200 18827 GET
http://kh.google.com/flatfile?f1-0023212010312-i.4 -
DIRECT/64.233.179.93 application/octet-stream
Sat Aug 13 10:59:54 2005 3026 192.168.1.50 TCP_MISS/200 20208 GET
http://kh.google.com/flatfile?f1-0023212010320-i.4 -
DIRECT/64.233.179.91 application/octet-stream
Sat Aug 13 10:59:54 2005 5746 192.168.1.50 TCP_MISS/200 20088 GET
http://kh.google.com/flatfile?f1-0023212010313-i.4 -
DIRECT/64.233.179.91 application/octet-stream
So, using some simpe ACLs (for kh.google.com for example) and Delay
Access features, you can easily make heavy limitation on Google Earth
software without making bad experiencies for google searching users.
Now let's go to Google Maps, http://maps.google.com/
This is Google Maps in the 'Map' view:
Sat Aug 13 11:10:23 2005 1347 192.168.1.50 TCP_MISS/200 6745 GET
http://mt.google.com/mt?v=w2.5&x=15294&y=25565&zoom=1 -
DIRECT/64.233.179.99 image/png
Sat Aug 13 11:10:23 2005 1352 192.168.1.50 TCP_MISS/200 7662 GET
http://mt.google.com/mt?v=w2.5&x=15294&y=25567&zoom=1 -
DIRECT/64.233.179.104 image/png
Sat Aug 13 11:10:24 2005 1686 192.168.1.50 TCP_MISS/200 10810 GET
http://mt.google.com/mt?v=w2.5&x=15294&y=25566&zoom=1 -
DIRECT/64.233.179.104 image/png
This is Google Maps in the 'Satellite' view:
(here's our kh.google.com again !!)
Sat Aug 13 11:11:14 2005 2169 192.168.1.50 TCP_MISS/200 19040 GET
http://kh.google.com/kh?v=3&t=tqtsrrqsssrt - DIRECT/64.233.179.93 image/jpeg
Sat Aug 13 11:11:14 2005 2169 192.168.1.50 TCP_MISS/200 11572 GET
http://kh.google.com/kh?v=3&t=tqtsrrqsssst - DIRECT/64.233.179.91 image/jpeg
Sat Aug 13 11:11:14 2005 2321 192.168.1.50 TCP_MISS/200 14974 GET
http://kh.google.com/kh?v=3&t=tqtsrrqssssq - DIRECT/64.233.179.93 image/jpeg
Sat Aug 13 11:11:16 2005 1701 192.168.1.50 TCP_MISS/200 11026 GET
http://kh.google.com/kh?v=3&t=tqtsrrqsssts - DIRECT/64.233.179.91 image/jpeg
Sat Aug 13 11:11:16 2005 1511 192.168.1.50 TCP_MISS/200 13554 GET
http://kh.google.com/kh?v=3&t=tqtsrrqssstq - DIRECT/64.233.179.93 image/jpeg
And this is Google Maps in the 'Hybrid' view:
Sat Aug 13 11:11:49 2005 385 192.168.1.50 TCP_MISS/200 4454 GET
http://mt.google.com/mt?v=w2t.1&x=476&y=796&zoom=6 -
DIRECT/64.233.179.104 image/png
Sat Aug 13 11:11:49 2005 442 192.168.1.50 TCP_MISS/200 3052 GET
http://mt.google.com/mt?v=w2t.1&x=479&y=800&zoom=6 -
DIRECT/64.233.179.99 image/png
Sat Aug 13 11:11:49 2005 465 192.168.1.50 TCP_MISS/200 2917 GET
http://mt.google.com/mt?v=w2t.1&x=477&y=796&zoom=6 -
DIRECT/64.233.179.99 image/png
Sat Aug 13 11:11:49 2005 571 192.168.1.50 TCP_MISS/200 2674 GET
http://mt.google.com/mt?v=w2t.1&x=475&y=800&zoom=6 -
DIRECT/64.233.179.104 image/png
Sat Aug 13 11:11:49 2005 445 192.168.1.50 TCP_MISS/200 1083 GET
http://mt.google.com/mt?v=w2t.1&x=475&y=797&zoom=6 -
DIRECT/64.233.179.104 image/png
Sat Aug 13 11:11:49 2005 389 192.168.1.50 TCP_MISS/200 2862 GET
http://mt.google.com/mt?v=w2t.1&x=479&y=796&zoom=6 -
DIRECT/64.233.179.99 image/png
Sat Aug 13 11:11:49 2005 391 192.168.1.50 TCP_MISS/200 3782 GET
http://mt.google.com/mt?v=w2t.1&x=476&y=800&zoom=6 -
DIRECT/64.233.179.99 image/png
And let's not forget the new Google Moon:
Sat Aug 13 11:13:13 2005 2366 192.168.1.50 TCP_MISS/200 22795 GET
http://moon.google.com/kh?v=2&t=ttqqq - DIRECT/66.102.7.99 image/jpeg
Sat Aug 13 11:13:13 2005 2678 192.168.1.50 TCP_MISS/200 22970 GET
http://moon.google.com/kh?v=2&t=tqttq - DIRECT/64.233.187.99 image/jpeg
Sat Aug 13 11:13:13 2005 3703 192.168.1.50 TCP_MISS/200 24877 GET
http://moon.google.com/kh?v=2&t=trsss - DIRECT/66.102.7.147 image/jpeg
Sat Aug 13 11:13:14 2005 3365 192.168.1.50 TCP_MISS/200 23140 GET
http://moon.google.com/kh?v=2&t=tqttt - DIRECT/66.102.7.104 image/jpeg
Sat Aug 13 11:13:15 2005 2579 192.168.1.50 TCP_MISS/200 25423 GET
http://moon.google.com/kh?v=2&t=tsrrr - DIRECT/66.102.7.99 image/jpeg
With these URLs and a transparent http proxy running, you can surely
imply hard limitations on bandwidth usage for Google Earth/Maps/Moon
services.
Only with iptables/QoS features ? Can be done, but i'm sure it will
not be so efficient and maybe not low-CPU solution as with squid. Of
course you can use string and look for 'kh.google.com' .... but that
would certainly blow your CPUs. You can use layer7, but you would have a
great amount of CPU usage as well.
Sincerily,
Leonardo Rodrigues
Thilo Schulz escreveu:
On Saturday 13 August 2005 00:38, fabricio bianco abreu wrote:
I would like to block it because a user using Google Earth consumes about
256kbps bandwith. I have 600+ users and only a 2Mbps link to the Internet.
I don't see how you would do that without doing a packet inspection for all
packets directed at www.google.com, as maps.google.com is - as you
undoubtedly already know - is an alias for www.google.com
You would have to do packet inspection and filter for maps.google.com. This
could be easily circumvented by using an SSL capable proxy.
Maybe QoS could do the trick for you. While allowing access to google earth,
it might discourage that user from excessively using it by restricting his
bandwidth to something like 64kbit/s while google itself is still perfectly
usable. It is generally a sensible idea to make use of QoS on a setup like
yours.
