Exchange Server 2007 provides built-in support for asynchronous replication modeled on SQL Server's "Log shipping"[8] in CCR (Cluster Continuous Replication) clusters, which are built on MSCS MNS (Microsoft Cluster Service—Majority Node Set) clusters, which do not require shared storage. This type of cluster can be inexpensive and deployed in one, or "stretched" across two data centers for protection against site-wide failures such as natural disasters. The limitation of CCR clusters is the ability to have only two nodes and the third node known as "voter node" or file share witness that prevents "split brain"[9] scenarios, generally hosted as a file share on a Hub Transport Server. The second type of cluster is the traditional clustering that was available in previous versions, and is now being referred to as SCC (Single Copy Cluster). In Exchange Server 2007 deployment of both CCR and SCC clusters has been simplified and improved; the entire cluster install process takes place during Exchange Server installation. LCR or Local Continuous Replication has been referred to as the "poor man's cluster". It is designed to allow for data replication to an alternative drive attached to the same system and is intended to provide protection against local storage failures. It does not protect against the case where the server itself fails. 

How does Bitcoin differ from traditional money

EDA adjustments caused instabilities in mining difficulty of the Bitcoin Cash system, resulting in Bitcoin Cash being thousands of blocks ahead of Bitcoin. To address the problem with stability, a change of the Bitcoin Cash DAA was implemented and the EDA cancelled. The change took effect on 13 November 2017. After the change, the Bitcoin Cash DAA adjusts the mining difficulty after each block. To calculate the difficulty for a new block, the Bitcoin Cash DAA uses a moving window of last 144 blocks.[36]

Does IBM own Blockchain