WAN Optimization

Obtaining Vendor-Specific Performance Validation Test Results Many network vendors today have results of performance validation tests and may make these available to customers. This information may not be publicly available due to the sensitive nature of the data. Most vendors make ... [full story]

IBM IBM (http://www.ibm.com) offers a broad array of 32-bit and 64-bit servers. These servers support operating systems offered by vendors such as Microsoft and Red Hat. Select servers include the POWER5 series processor that is designed to specifically support operating systems such ... [full story]

Central Processing Unit There are several factors to take into consideration when selecting a processor. As the CPU speed war continues, competition will only benefit your applications and their performance. The continual evolution of processors will make selecting the correct processor ... [full story]

Cache Capacity Layer 2 and Layer 3 caches reside in the processor chip. These caches accelerate the processor's ability to receive data. Processors today support caches that range in size from 1 MB to 24 MB or larger. Typically, the larger ... [full story]

Front Side Bus Speed The front side bus is a significant factor in the server's ability to move data about the server. The numerical rating of a server's front side bus designates at what speed the processor can transfer data to ... [full story]

Dual-Core Support A dual-core processor is simply a single processor chip that contains two processors that can work in parallel. A common benefit of a dual-core processor is that the individual processors will each have their own primary cache, or Level ... [full story]

Hyper-Threading Hyper-threading and Super-threading are offerings that are specific to processors manufactured by Intel Corporation. Hyper-threading allows a single processor to appear as if two separate processors exist. Super-threading allows a thread, or thread of execution, to be shared with a ... [full story]

Support for 32-Bit and 64-Bit Architectures Some processors support a 32-bit architecture, whereas others support a 64-bit architecture. As operating systems evolve toward a greater array of 64-bit support, applications must also support the ability to communicate with a 64-bit processor. ... [full story]

Random Access Memory Memory selection for servers is a constantly evolving process. Although naming is very similar between types, the performance and capabilities differ significantly. Common server memory implemented today includes double-data-rate (DDR), synchronous dynamic random-access memory (SDRAM), double-data-rate two (DDR2), ... [full story]

Hewlett-Packard Hewlett-Packard (http://www.hp.com) offers several different server platform product lines and a proprietary operating system called HP-UX. In addition to supporting HP-UX, the Hewlett-Packard server platforms support other operating systems, such as Microsoft Windows Server 2003, Novell Corporation's NetWare, Red Hat ... [full story]

Red Hat Red Hat (http://www.redhat.com) offers two versions of the Enterprise Linux operating system for data center computing, Linux AS and Linux ES. Red Hat is an operating system vendor that supports an array of processor platforms, including Intel Corporation's Itanium ... [full story]

Establishing a Redundancy Plan One of the most important factors in network stability is the redundancy plan. Redundancy planning and implementation can be leveraged at any place within the network, ranging from the data center application servers to the remote branch ... [full story]

Stabilizing the Client and Server Network Connections The client and server also are large factors in network stability and application performance, starting with the connection point to the network, the NIC. For all devices, if the client or server network connection ... [full story]

Operating System Barriers to Application Performance The impact the clients and servers play in perceived network stability and application performance does not stop with the connection to the network. Several factors exist that are commonly not taken into consideration when looking ... [full story]

Microsoft Corporation In the data center, Microsoft offers several different editions of the popular operating system Windows Server 2003 R2. The operating system and third-party device drivers must be compatible with the hardware platform, which must explicitly support the operating system. The ... [full story]

TCP Chimney Offload TCP Chimney Offload is Microsoft's software implementation that directly supports TCP Offload Engine (TOE) NICs. The subject of TOE is discussed later in this chapter, in the section "Network Interface Cards." TCP Chimney Offload, when combined with a ... [full story]

Receive-Side Scaling Receive-side Scaling addresses the common challenge of load allocation to a single processor within a multiprocessor server. A single network processor in a server handles all network traffic. For servers that have high utilization levels and multiple processors, one ... [full story]

NetDMA NetDMA is the third offering of the Windows Server 2003 Scalable Networking Pack. NetDMA requires supporting hardware, which optimizes data flow through a server. NetDMA reduces the dependency on the server's processor to manage moving data between the network adapter ... [full story]

Sun Microsystems Sun Microsystems (http://www.sun.com) offers hardware and operating system platforms for the data center. All Sun Scalable Processor Architecture (SPARC) powered server platforms support the Solaris operating system. Sun also supports AMD powered server platforms, which adds support for Red ... [full story]

Disk Storage The spinning disk is inevitably going to be the choke point for application performance in many server environments, as information is exchanged between the server bus and magnetized areas on a spinning platter. Typical storage deployments have changed radically ... [full story]

Serial Attached SCSI (SAS) Serial attached SCSI (SAS) is the next generation of SCSI interconnect where communication with the drives occurs in serial, not parallel, between the controller and attached drives. With serial operation, clock rates can be increased due to ... [full story]

Fiber Channel Fiber Channel (FC) attached storage is commonly connected to the server via Lucent connectors (LCs) embedded within a small form-factor pluggable (SFP) optical adapter, such as a PCI host bus adapter (HBA). HBAs have throughput ratings of up to ... [full story]

Post-Queuing Optimization Traffic that has been released from a queue by the scheduler according to queuing policy and shaping then passes through a series of post-queuing optimizations. Post-queuing optimizations help to ensure optimized delivery of packets across the network by interleaving ... [full story]

Understanding Accelerator Control Features and Integration The previous sections in this chapter outlined a few of the many key network technologies that you can employ to help understand how the network is used and to effectively align network resources with the ... [full story]

Overview of Accelerator Technology Network accelerators provide a combination of functions to help improve the performance of applications over a network. These functions help to mitigate many of the performance-limiting factors in enterprise networks today such as those discussed in previous ... [full story]

WAN Optimization WAN optimization is a set of services that overcomes the performance limitations caused by transport protocols, network conditions, and network utilization. The three most common WAN optimization services employed by accelerators include TCP optimization Data suppression Compression Many accelerators offer WAN optimization capabilities ... [full story]

TCP Optimization TCP is particularly challenged in WAN environments due to the connection-oriented, guaranteed-delivery behavior of the protocol. Furthermore, TCP generally has only a limited amount of memory capacity assigned to each connection, meaning only a small amount of data can ... [full story]

Integrating Accelerators into the Network To understand how accelerators coexist with the foundational network technologies for visibility, control, and resource alignment, it is also important to understand how accelerators integrate into the network. Integrating accelerators includes deploying accelerators and delivering to ... [full story]

Architecture of Accelerator Services All accelerator devices (and acceleration technology in general) have some posture to services deployed in the network. These network services include any action that can be performed against network packets and flows, including network visibility, monitoring, end-to-end ... [full story]

Nontransparent Accelerators Nontransparent accelerators are designed to optimize traffic that has been redirected to it and explicitly forward the optimized traffic to a statically defined or dynamically discovered peer through an explicit connection to that peer accelerator. In this way, the ... [full story]

Queuing and Scheduling Once traffic has been classified (identified) and pre-queuing operators have been applied (policing, dropping), the router then queues traffic for service onto the next-hop link. Queuing is defined as the way a node temporarily stores data while waiting ... [full story]

Differentiated Services DiffServ is more commonly used than IntServ and is referred to as soft QoS due to its reliance on per-hop behaviors at each node in the network, dictated largely by a common understanding and configuration of how to handle ... [full story]