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Kirt Blattenberger - RF Cafe WebmasterCopyright
1996 - 2022
Kirt Blattenberger,

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...

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Is Your Domain Being Blocked by a Country?
Kirt's Cogitations™ #275

greatfirewallofchina.org test of RFCafe.com - RF CafeCA Technologies "App Synthetic Monitor" for RFCafe.com - RF CafeRecently, a company based in China contacted me about advertising on RF Cafe. After doing a lot of up-front work for them creating advertising materials (Highlighted Ad, 160x600-px banner graphic, etc.), the representative informed me that he cannot access the RFCafe.com domain from his location. It is really difficult to conduct business when the customer cannot review your work, so at least for now, I am going to pass on the opportunity. The obvious question that arises from the experience is whether RFCafe.com is being blocked by China, and how do I find out?

Fortunately, a few options exist with websites that will perform the check for you by pinging your URL from servers within multiple countries. Some, such as GreatFirewallOfChina.org, tests from inside China using servers in Beijing, Shenzhen, Inner Mongolia, Heilongjiang Province, and Yunnan Province. RFCafe.com looks good from China according to this service, so I wonder why the aforementioned China-based company cannot reach RFCafe.com?

Wanting to try at least one other domain resolution service to make certain access from China was possible, I used CA Technologies' "App Synthetic Monitor." It tests from numerous countries. The free version checks from servers in China, the UK, Germany, Italy, Spain, Sweden, Poland, Switzerland, and the U.S. RFCafe.com looks good from all locations. There is a subscription service that monitors access status from up to 48 countries.

For kicks, I typed in a few domains into GreatFirewallOfChina.com to see who might be blocked. News websites are the best candidates for trial since China is known to block sources considered generally unfavorable to their policies. FoxNews.com is blocked - no surprise there. NYTimes.com is also blocked, as is WSJ.com (Wall Street Journal). Those having access include CBSNews.com, CNN.com, DrudgeReport.com (very surprised), HuffingtonPost.com, NBCNews.com, and NPR.org. Testing some U.S. government websites produced varied results. WhiteHouse.gov is banned, along with FCC.gov and CIA.gov (LOL).  NIST.gov, FBI.gov, NASA.gov, ESA.int, and DHS.gov are allowed. Go figure.

If your company markets products and/or services to countries outside your homeland, you should test access occasionally to make sure you are not being blocked. If you are blocked, I have no idea what to do about it, but at least you will know.

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These original Kirt's Cogitations™ may be reproduced (no more than 5, please) provided proper credit is given to me, Kirt Blattenberger.

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   Cog·i·ta·tion [koj-i-tey'-shun] – noun: Concerted thought or reflection; meditation; contemplation.
   Kirt [kert] – proper noun: RF Cafe webmaster.

These items are an archive of past Topical Smorgasbord items that have appeared on the RF Cafe homepage. In keeping with the "cafe" genre, these tidbits of information are truly a smorgasbord of topics. They all pertain to topics that are related to the general engineering and science theme of RF Cafe. Note: There is also a huge collection of my 'Factoids' (aka 'Kirt's Cogitations') that might interest you as well.

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| 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 |



Posted June 18, 2016