NAT is used for conserve IP addresses on the Internet which are expensive and limited in number. Also, NAT provides security by hiding the inside network from the Internet.
Generic Routing Encapsulation tunnels provide a pathway that traffic can only enter at configured endpoint and leave at the other configured endpoint. It provides new packet headers to ensure delivery to wanted destinations. GRE tunnels do not provide true confidentiality like encryption does, but it can carry encrypted traffic. End point is configured logically at the interfaces through which the traffic is carried.
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Anyone on that network of blockchain and reach and transact with another user instantly, no matter where they are in the universe, and regardless of business hours. No intermediary is needed to filter, block or delay a transaction between two or more users. Any node is allowed to provide service based on their knowledge of transactions everywhere else in that network.
Also, blockchain and applications on top of them create their own (distributed) economies, a variety of size and vibrancy. It is a key feature that will be expanded later on this book.
Vibrant/ vibrancy: something is full of energy and life.
Blockchains hold trust as an atomic unit of service. In essence, it is a function that is delivered. And trust does not only apply to transactions, it is extended to data, services, processes,business logic and terms of agreement. Basically, trust can exist in everything that can be digitized as an inherent and related values attached to it.
Inherent:
the inherent of something are the necessary parts and natures of it.
