MaxCDN, previously also known as NetDNA and a leading provider of innovative Content Delivery Networks, announced that it had now added a HTTP Blacklisting feature for images similar to the HTTP Whitelisting feature to add better control over hotlinking while ensuring that search-engines are still able to index and show the images as part of their search results.
MaxCDN mentioned that while the whitelisting could be used in a similar way, the content publishers needed to ensure that all search engine crawlers etc. are whitelisted and that could cause some indexing to get missed. The blacklisting, since it works the other way, provides more control on which domains to restrict from hotlinking images and ensures SEO value of images is not lost.
Additional details on how to implement/deploy this feature is explained in the original post below.
Original Post at: https://www.maxcdn.com/blog/http-referer-blacklisting/
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