Data Backup Whitepapers and Ebooks

Disk drives are tools to read data from and write data to a persistent storage.  The most important parameters to look for in a disk drive are: capacity, seek time, access time and throughput. They have evolved over the years - from the earliest Advanced Technology Attachment (ATA) drives to the latest Storage Area Network (SAN) drives. Disk drives can be internal or external. An internal disk drive is hosted inside a computer. An external drive is a separate device either connected to the machine or hosted in a cloud.

  • Free Sneak Peak Preview Chapter of ActiveMQ in Action""
    An understanding of storage mechanisms for messages in an ActiveMQ message store aid in configuration and provide an awareness of what takes place in the ActiveMQ broker during the delivery of persistent messages. Messages sent to queues and topics are stored differently, because some storage optimizations can be made with Topics that do not make sense with Queues, as we will explain. Storage for queues is straightforward. Messages are stored in a first-in, first-out (FIFO) order (see figure 1). One message is dispatched to a single consumer at a time. Only when that message has been consumed and acknowledged can it be deleted from the broker's message store. #12;For durable subscribers to a topic, each consumer gets a copy of the message. In order to save storage space, only one copy of a message is stored by the broker. A durable subscriber object in the store maintains a pointer to its next stored message and dispatches a copy of it to its consumer, as shown in figure 2. The message store is implemented in this manner because each durable subscriber could be consuming messages at different rates or not running at the same time. Also, because every message can have many consumers, a message cannot be deleted from the store until it has been successfully delivered to every interested durable subscriber.
  • Best Practices When Enabling Smart Card Authentication in a KVM System
    While many organizations have employed smart card identification to enhance their physical security infrastructure, KVM (Keyboard, Video & Mouse) system users in particular can benefit greatly from the two-factor authentication that a smart card inherently provides to the logical realm (access to software and application systems on servers). However, whereas a physical security system that incorporates smart cards is straightforward to implement, logical security using PKI-based authentication (Public Key Infrastructure) incurs very specific practical obstacles during implementation in a data center, network operating center, lab or any facility that relies on a KVM system for efficient operation. While smart card readers themselves are inexpensive, 1-to-1 mapping of card readers to server hardware neutralizes many of the efficiencies that a high-density server environment with few user touchpoints provides. IT managers thus face a difficult decision: greater security or greater convenience. A similar problem has been faced previously. Before the modern server boom, most computer rooms employed a keyboard and monitor for each server � a 1-to-1 mapping. But KVM switching technology later eliminated this inefficient deployment, allowing one set of keyboard, monitor and mouse peripherals to be deployed to many servers at once. By extending its peripheral set to include card readers, modern KVM switches with smart card capabilities can allow data center managers to enjoy the best of both worlds: greater security and greater convenience.
  • KVM Smart Card Authentication Best Practices
    While many organizations have employed smart card identification to enhance their physical security infrastructure, KVM (Keyboard, Video & Mouse) system users in particular can benefit greatly from the two-factor authentication that a smart card inherently provides to the logical realm (access to software and application systems on servers). However, whereas a physical security system that incorporates smart cards is straightforward to implement, logical security using PKI-based authentication (Public Key Infrastructure) incurs very specific practical obstacles during implementation in a data center, network operating center, lab or any facility that relies on a KVM system for efficient operation. While smart card readers themselves are inexpensive, 1-to-1 mapping of card readers to server hardware neutralizes many of the efficiencies that a high-density server environment with few user touchpoints provides. IT managers thus face a difficult decision: greater security or greater convenience. A similar problem has been faced previously. Before the modern server boom, most computer rooms employed a keyboard and monitor for each server � a 1-to-1 mapping. But KVM switching technology later eliminated this inefficient deployment, allowing one set of keyboard, monitor and mouse peripherals to be deployed to many servers at once. By extending its peripheral set to include card readers, modern KVM switches with smart card capabilities can allow data center managers to enjoy the best of both worlds: greater security and greater convenience.