Trusted Execution Environment (TEE), Chinese translation of "the Trusted Execution Environment," privacy computing in recent years is introduced the concept of a "relatively new" (as early as 2006 ARM has proposed the concept of similar TEE TrustZone), but until recent years, Intel SGX technology applied to the TEE, although it seems the TEE in the word is just a part of privacy to calculate, but due to its high security code Execution space can be formed, in the field of block chain can effectively solve the intelligent contract Execution code leak problems, therefore many block chain project to research and explore the practical application of the TEE, considering that the newer technology, Chinese Internet few simple introduction of it, here we will learn a little about what the TEE, and on behalf of the TEE application technology, Intel SGX,

01
What is the TEE?
TEE the trusted execution environment is single chip level division of a "region", this area will not necessarily possess the physical location of the chip, maybe it's just execution of logically occupy a certain space, this space, in the Intel called Enclave in SGX, while in the ARM TrustZone called Secure World, the area responsible for code and data storage to provide a safer place, to ensure the confidentiality and do not tamper with the sex,



Execute the code in the absence of the TEE, chip, or the code stored in the chip internal cache, or stored in the chip external "memory" or hard disk, but whether is it in the cache memory, all of the code and execution can be read by other programs, this leads to code execution, there is no privacy, for some to hide this code can be a serious hazard, and the application of code process, and the TEE in the chip level to provide an independent area code execution, the independent area can't from the software and hardware level obtained by other programs, to ensure that the code in this area of confidential and safe,

TEE that is not affected by the external code execution area, through the sensitive information, such as pay password into the TEE, password authentication through the TEE provided interfaces, such as long as the data within the TEE is not covered, or contains the TEE chips are not lost, TEE can always offer to pay the password verification, and pay the password can hardly be acquired outside the program, on the other hand, the TEE will be through the API interface on a regular basis to provide proof data integrity, ensure that the external environment can be stored in the inside of the TEE value has not changed,



If you want to figuratively speaking, TEE is like a embassy, we have to set up the Chinese embassy in the United States as an example, the embassy as a world outland, the United States can see Chinese embassy do anything, including the destruction of data, etc., but don't know the embassy destruction of data for detailed information, and also have the right to go to embassy intervention all the behavior of

02
Intel SGX
Intel SGX (Intel Software Guard Extensions) is provided by the Intel TEE, because in the past decade, Intel in the market of the mainstream position, Intel SGX also naturally became one of the most commonly used TEE solutions, in SGX, TEE environment used to execute code is called the Enclave (Enclave), in the Enclave data can ensure the confidentiality and integrity; And Intel also provides a is used to verify whether some results performed by the SGX, to ensure that a malicious person disguised as SGX to steal information; The SGX scheme provides a broader security boundary, memory data, including the Bios is unable to get to the encrypted data in SGX,

In addition to Intel SGX, almost all the major chip companies to provide the solution for the TEE, is TrustZone scheme in the ARM, and in AMD is PSP, other mobile terminal chip such as mediatek, qualcomm is widely adopted the TEE technologies, such as

03
Wisdom can Chain?
The answer is yes,
TEE technology as a kind of privacy, also applies to block Chain field of study to ensure privacy by encryption, in Wisdom in the Chain, although adopted the hybrid consensus transaction processing efficiency is achieved, but as long as as a decentralized network, to save the global book block Chain nodes block production node, the more the efficiency of network will fall (because the Internet all the state synchronization time extension), is a classic CAP theorem, however, use the TEE technology, can be part of the transaction execution in the form of encryption code into the TEE in the space, then so can omit the TEE step of validation, even in the case of extreme optimism can omit the results of validation, so you can make up for the network block production node number rising efficiency decline,

In addition, because the TEE can be classified to perform intelligent contracts, introducing the TEE Wisdom Chain can also make its privacy calculation ability, scrip trading can gain not only privacy, transaction implementation logic and process can ensure privacy, and the privacy is verifiable for stakeholders, through the TEE, Wisdom Chain can also become a have high ability of privacy of public Chain,

TEE, however, is not a technology without faults, first of all, by far the most widely used Intel SGX, in addition to replace the equipment requires a lot of cost, because there need to be validated, and validation is initiated by Intel to maintenance center server, this is clearly not satisfy block chain behavior of the theory of "decentralization", and this way also exist man-in-the-middle attack and the risk of Intel wickedly, and second, the TEE space is limited, this leads to a TEE is unable to perform a very complicated transaction logic, it is difficult to migrate to a single TEE like Uniswap exchange environment; Finally, the current commonly used TEE scheme, is unable to communicate with each other between each trusted space, how to communicate across the device by the TEE also needs to wait for the efforts of technical personnel,

However, to be sure, the future will be more block chain project to protect privacy, the plan of the TEE TEE program is already on a mobile phone application, large-scale application in the field of TEE in the chain of blocks will not only a theory,