Here it goes:
Behind a ISP-wide cache.
Any 'traceroute' passes by transtelco.net (ISP used to have their own infraestructure for voip services Megafon) now i have 5/6? DNS jumps! and all my traffic going to Transtelco.
traceroute to news.ycombinator.com (198.41.191.47), 30 hops max, 60 byte packets
1 customer-GDL-**-***.megared.net.mx << 177.230.**.*** Dynamic IP, GDL is the city of the company
2 10.0.28.62 (10.0.28.62) 8.939 ms 8.941 ms 8.935 ms
3 10.2.28.195 (10.2.28.195) 8.912 ms 8.903 ms 8.891 ms
4 pe-cob.megared.net.mx (189.199.117.***) 8.878 ms 8.866 ms 14.201 ms << COB is the user city
5 10.3.0.29 (10.3.0.29) 23.494 ms 23.483 ms 23.408 ms
6 10.3.0.13 (10.3.0.13) 22.842 ms 19.609 ms 19.596 ms
7 10.3.0.10 (10.3.0.10) 19.560 ms 19.555 ms 19.536 ms
8 201-174-24-233.transtelco.net (201.174.24.233) 19.527 ms 20.650 ms 19.468 ms
9 201-174-254-105.transtelco.net (201.174.254.105) 34.239 ms 31.793 ms 31.268 ms
10 fe3-5.br01.lax05.pccwbtn.net (63.218.73.25) 31.792 ms 31.736 ms 33.533 ms
11 any2ix.coresite.com (206.223.143.150) 32.834 ms 33.221 ms 33.429 ms
12 ae3-50g.cr1.lax1.us.nlayer.net (69.31.124.113) 41.288 ms 41.228 ms 41.231 ms
13 ae2-50g.ar1.lax1.us.nlayer.net (69.31.127.142) 42.632 ms ae1-50g.ar1.lax1.us.nlayer.net (69.31.127.138) 35.192 ms 33.860 ms
14 as13335.xe-11-0-6.ar1.lax1.us.nlayer.net (69.31.125.106) 35.143 ms 44.714 ms 44.666 ms
15 198.41.191.47 (198.41.191.47) 37.638 ms 37.239 ms 36.997 ms
I don't know how normal or ethic is this type of cache. No download limits, I have the 10mb and get 20mb(2000-2300kbps) downloads, for uploads is limited to 1mb.
As long as they don't tamper with the data I think an HTTP cache is perfectly OK. HTTP has loads of built-in mechanism for that kind of caching. It saves bandwidth upstream, not least for website owners, and may make your web browsing speed faster if the proxy is good.
Tampering with the data, however, is not OK at all. In the U.S. I believe it may make the ISP exempt from for example the safe harbor clauses in the DMCA.
Some of the big content providers like Netflix are even reportedly making caching deals for their content. Both the content provider and the ISP get better performance and less exterior bandwidth.
Your traceroute doesn't show that you're behind a cache, just that your ISP uses transtelco.net for IP transit; at least to the destinations you tried.
