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RPO & RTO - ITIL Information Technology Infrastructure Library

Recovery Point Objective (RPO) A  recovery point objective  (RPO) is defined by business continuity planning. It is the maximum targeted period in which data might be lost from an IT service due to a major incident. The RPO gives systems designers a limit to work to.                                 Data Loss Period based on below calculation Recovery Time Objective (RTO) The  recovery time objective  (RTO) is the targeted duration of  time  and a service level within which a business process must be restored after a disaster (or disruption) in order to avoid unacceptable consequences associated with a break in business continuity. Recovery Point Objective (RPO) The disaster recovery term Recovery Point Objective (RPO) is a widely used term. However, it’s often difficult to provide a simple definition and explain its important in the recovery process. But here it goes… Recovery Point Objective is the point in time you can recover to in the event of a d

CIDR Classless Inter-Domain Routing

Classless Inter-Domain Routing Acronym. CIDR.  Classless Inter-Domain Routing ; normally an IP address notation such as 192.168.1.0/24 indicating a block of addresses. The number after the slash indicates how many bits are in the mask; bits to the right are not masked. CIDR (Classless Inter-Domain Routing or supernetting) CIDR (Classless Inter-Domain Routing, sometimes called  supernetting ) is a way to allow more flexible allocation of Internet Protocol ( IP ) addresses than was possible with the original system of  IP address  classes. As a result, the number of available Internet addresses was greatly increased, which along with widespread use of network address translation ( NAT ), has significantly extended the useful life of IPv4. cidr calculator Follow below link http://www.subnet-calculator.com/cidr.php http://jodies.de/ipcalc?host=192.16.0.1&mask1=16&mask2= CIDR - Classless Inter Domain Routing CIDR - Classless Inter Doma

ELB - Elastic Load Balancer

Elastic Load Balancer We launched Elastic Load Balancing (ELB) for AWS  (see  New Features for Amazon EC2: Elastic Load Balancing, Auto Scaling, and Amazon CloudWatch  to see just how far AWS has come since then). Elastic Load Balancing has become a key architectural component for many AWS-powered applications. In conjunction with  Auto Scaling , Elastic Load Balancing greatly simplifies the task of building applications that scale up and down while maintaining high availability. On the Level Per the well-known  OSI model , load balancers generally run at Layer 4 (transport) or Layer 7 (application). A Layer 4 load balancer works at the network protocol level and does not look inside of the actual network packets, remaining unaware of the specifics of HTTP and HTTPS. In other words, it balances the load without necessarily knowing a whole lot about it. A Layer 7 load balancer is more sophisticated and more powerful. It inspects packets, has access to HTTP and HTTPS headers