从广义上来看,网络交换机分为两种:广域网交换机和局域网交换机。广域网交换机主要应用于电信领域,提供通信用的基础平台。而局域网交换机则应用于局域网络,用于连接终端设备,如PC机及网络打印机等。从传输介质和传输速度上可分为以太网交换机、快速以太网交换机、千兆以太网交换机、FDDI交换机、ATM交换机和令牌环交换机等。从规模应用上又可分为企业级交换机、部门级交换机和工作组交换机等。各厂商划分的尺度并不是完全一致的,一般来讲,企业级交换机都是机架式,部门级交换机可以是机架式(插槽数较少),也可以是固定配置式,而工作组级交换机为固定配置式(功能较为简单)。另一方面,从应用的规模来看,作为骨干交换机时,支持500个信息点以上大型企业应用的交换机为企业级交换机,支持300个信息点以下中型企业的交换机为部门级交换机,而支持100个信息点以内的交换机为工作组级交换机。 [3] 

Because the blockchain works by verifying transaction history, and this verification process is labor-intensive and slow, only so many transactions can be verified in a certain timespan. So, if you sell your Bitcoin, but the purchase isn’t confirmed by the blockchain network, and the price of the currency changes, the sale won’t process. You'd have to sell your Bitcoin at whatever the new rate is (if you so choose to sell). Also due to the reality of blockchain, as well as for other reasons thus far unidentified, the Coinbase payout system can sometimes be unreliable. There have been reports of extensively delayed payout periods, and bugs sometimes keep the site from running as efficiently as it could or should. A word to the wise: if you are going to invest in and speculate on cryptocurrencies, do so carefully.​

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Bitcoin (BTC) is the world’s first decentralized digital currency and payment system and is by far the most known and valuable cryptocurrency. It was created in 2009 by an anonymous person or group called Satoshi Nakamoto. Bitcoin enables transactions to be sent peer-to-peer without passing through a central authority. The transactions are recorded on a decentralized public ledger called the blockchain and each payment acquires a small transaction fee to cover the cost of the network. The total supply of Bitcoin is 21 million and it’s smallest unit of bitcoin is called a Satoshi, it’s a hundred millionth of a bitcoin – 0.00000001 BTC. The creation of Bitcoin’s is happening through mining. Miners have the task to validate transactions and keep the network secure. Their efforts are rewarded by new minted Bitcoins and transactions fees. Bitcoin can be exchanged for fiat or other cryptocurrencies, products and services. Over 100,000 merchants and vendors accepts bitcoin as a payment.

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