Originally Posted by
NeedKarma
I'll bet highly that the filtering is done right at the ISP level. Probably packet inspection so it matters not what web proxy he uses the "offending" sites will be blocked.
Dialing in long distance to another ISP outside the country would be a good way to test this.
This is entirely possible though I'm not entirely convinced this is what's happening.
This kind of filtering where protocol level packet inspection (i.e. web traffic inspection) takes a great deal of horsepower to accomplish vs. a simple Access Control Lists (ACL) or IP blocking at a router level which takes a lot less horsepower to accomplish. One thing we never asked was what behavior is eyad1969 getting when he tries to access various proxies?
- Is the site not coming up and timing out after a while?
- Is the site not coming up and timing out immediately?
- Is a web response coming back that says the site is blocked?
- What are the results of doing a "tracert" or "ping" to the various proxies?
- What are the results of doing a "tracert" or "ping" to the sites you want to visit in the first place?
- Are all the sites you're trying to visit using port 80?
- Have you tried accessing proxies that use port 80 as a service instead of 8080, 3128, or other common proxy ports?
Depending on the answers and thus what potentially is happening we could recommend a good course of action.
Assuming that NeedKarma is dead on about packet filtering. One thing that defeats against packet inspection is to go with an HTTPS proxy. If they are doing packet inspection (and nothing else) then https ought to take care of that since they won't be able to inspect inside the packets.