Desktop wallpaper free download. I’m being called in as IT consultant by my wife, who uses SPSS. Today, mysteriously, it started INTERMITTENTLY failing with messages like “Serialization scheme was not recognized” and “Could not instantiate a required server object”. I’m being called in as IT consultant by my wife, who uses SPSS. Today, mysteriously, it started INTERMITTENTLY failing with messages like “Serialization scheme was not recognized” and “Could not instantiate a required server object”. ![]() As promised in my last blog I will ponder a bit about the necessity to separate serialization from sending functionality for realization of security measures like the qualified electronic user signature (QEUS), legally required by some modern electronic business processes My main thread will run along the following line: First I will give a typical example, where serialization and sending is not separated, but where serialization is delegated into sending functionality instead. Second I will explain what an electronic signature is and why direct access to serialization functionality is relevant for its application. Third I will outline what is special about a QEUS and last but not least I will discuss the consequences for a communication architecture, if we follow this line of thoughts. A typical example of delegating serialization into sending functionality A typical example, where serialization and sending are inseparably connected, occurs within every technology of remote calls of typed functions, where serialization becomes delegated into some sort of sending functionality. A typed function is a mapping between an instance of an input type and an instance of an output type. In the object oriented world, this may be extended by a second mapping of internal typed instances. To let a typed remote function call look like a local function call in the program description, the proxy technology has been invented. It was recognized that the necessary data processing for calling a remote function follows a stereotyped scheme: Within the function consumer, the internally structured represented input data has to be serialized according to certain rules and send away. Within the function provider, this input data has do be deserialized following the reciprocal rules and feed into the actual local function. For passing the output parameters back, the same schema applies in the backward direction. So, the call of a typed remote function implies delegating serialization into functions with implicit sending semantics. Remark: The question of synchronicity is unrelated to this issue, because it relates solely to the behavior of the function consumer. The provider is unaware whether the consumer holds its context of the function call implicitly and blocks further processing or explicitely and has to look it up when the answer comes back. Electronic Signature To understand what an electronic signature is, we have to understand the principles of asymmetric encryption technique first. With asymmetric encryption, there exist a pair of two keys, which relate to each other via encrypt() and decrypt() functions. Encrypting data using the first key, requires decrypting it with the second and vice versa. If we declare one key as ‘private’, i.e. ![]() Obviously, the encryption aspect of communication does relate to the receiver of the data, since it is his pubic key, which has to be used for encryption and his private key, which has to be used for decryption. A fact that makes delegation of encryption into sending functionality straight forward, creating secure transport channels. An electronic signature denotes data which can be used to unequivocally prove that some other data has changed or remained invariant. Practically this is achieved by calculating a hash sum of some serialized data and encrypt this hash sum with the owned private key. The recipient of the data then can calculate its own hash sum of the data and has to compare this hash sum with the decrypted hash sum, provided by the sender. Signature relates exclusively to the sender of the data, since its private key is used to encrypt the hash sum and its public key is used to decrypt is again. It is quite interesting to notify that signature relates to the logical sender system while encryption relates to the logical receiver system. Both require their respective system to be well defined. Inverting this logical relation, we can say, that difficulties in providing end-to-end security with signature and encryption technique may indicate that our system notion is not well (enough) defined. Both, encryption and signature essentially requires the data to be a string of characters, i.e.
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