0428 VPN & Blockchains

NAT

The Internet has experienced an explosivegrowth far more than the original designers can ever foresee. So the address spaceof IP 4.0 becomes less available.

So one solution to this problem is NAT(Network Address Translation) where outsider can only see one or a few addresses from the boundary device (usually router or firewall). One advantage for NAT is that the private network cannot receive IP connection from outside unless the boundary gateway has been configured specifically to allow the connection. Also, the boundary devices are completely transparent to source and destination devices.

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Blockchains

The cryptocurrency is at the heart of the blockchain. When the cryptocurrency is treated like any other currency. Blockchaincan offer an innovating environment for cryptocurrency and being a brand newfinancial service marketplace. But firstly, cryptocurrency must solve its biggest issue, the volatility, since the volatility is subsided, then variety ofdevelopments like derivatives, swaps, loans and etc. will grow rapidly on the blockchain.

Peer-to-Peer network

There is no “central” about blockchains. Architecturally,the base layer of the blockchain is peer-to-peer network. Blockchains pushesfor decentralization via peer processing at its node location. Each node verifies other transaction at peer-to-peer level. In essence, the blockchain is like thin computing cloud that is truly decentralized.