The KeeeX server produces a certificate summary like this one every 5 minutes, to ensure that timestamp requests enter a block as fast as possible (on the Bitcoin blockchain, blocks occur every 10 minutes on average). This timestamp certificate may hence adequately seen as a kind of sidechain, that prevents from pushing too many transactions on the Bitcoin blockchain. It also mutualizes the cost of timestamping of course, which allows KeeeX to provide this as an unlimited service.
This certificate displays at the top below its own b58 encoded identifier computed from an sha224 hash. These settings produce a 39 character string that fits within the current 40 byte Bitcoin blockchain limit. Again, under the current state of the technology, it is not possible to counterfeit this identifier by producing another certificate file with the same id.
This certificate's id has been registered as OP_RETURN data on the Bitcoin transaction below that can for your convenience be verified by following the links below. The present certificate file hence creates a proof chain from the Bitcoin blockchain ledger to your file, that provides evidence that at the transaction date you had knowledge of the identifier of your file, which you may or not have decided to keep private or share publicly. This idx does not by itself expose your data in any way. By using KeeeX you also had a chance to digitally sign your original file.
Although KeeeX will make its best efforts to keep this certificate accessible and indexable by search engines, we cannot guarantee this. If some file id is of interest to you it is thus your responsibility and interest to download it and make sure to preserve it indefinitely. Once downloaded, you may verify its integrity using the KeeeX app. Depending upon its version, the KeeeX app may automatically retrieve this file on your behalf.
You may wonder why we chose to mutualise this certificate for potentially a large number of files. The reason is that a single certificate may provide a proof of existence for an unlimited number of files and no blockchain, BItcoin inclusive, is designed to satisfy the massive notarisation needs, since both the block size and rate are constrained.