Data Center Infrastructure Resource Guide

A Comprehensive Reference

Data centers are the "nerve centers" of the modern economy, housing the critical IT infrastructure that enables organizations to conduct business around the clock and around the world. Anixter’s Data Center Infrastructure Resource Guide is a comprehensive reference document designed to help professionals design, build, and manage these specialized, mission-critical environments. This article summarizes the key content from this essential guide.

Why This Guide Matters

Data centers are unique, "hardened" facilities dedicated to providing uninterrupted service to business-critical data processing operations. They demand:

• 7×24×365 availability with fail-safe reliability and continuous monitoring.
• Power management and network communications with redundancy and path diversity.
• Network security, physical access control, and video surveillance.
• Zoned environmental control and sophisticated fire suppression systems.

The guide serves as a desktop resource, providing standards-based best practices to navigate the complexities of data center design, from power and cooling to cabling infrastructure and security. It is structured into five main sections, covering everything from the basics of what a data center is to key considerations for deploying solutions.

Section 1: Introduction to Data Centers

What is a Data Center?

A data center is a facility that centralizes and consolidates Information Technology (IT) resources. It provides the infrastructure for server consolidation, business continuity, database management, eBusiness, and many other initiatives. Data centers fall into two major categories:

• Corporate Data Centers (CDCs): Owned and operated by private corporations, institutions, or government agencies to support their own data processing and Web-oriented services.
• Internet Data Centers (IDCs): Owned by commercial operators (telcos, service providers) to provide outsourced IT services like Web hosting, colocation, managed servers, and content distribution on a commercial basis.

Common Attributes of All Data Centers

Despite differences in scale, both CDCs and IDCs share common functions, including:

• Internet access and wide area communications.
• Application hosting and content distribution.
• File storage and backup.
• Failsafe power and adequate HVAC.
• High-performance cabling infrastructure.
• Security (access control, video surveillance).

Section 2: Data Center Design Considerations

Professional Engineering and Power Requirements

Successful data center design begins with professional engineering due to the complex coordination of HVAC, electrical, mechanical, and telecom trades. The guide notes that data center power consumption has skyrocketed, doubling between 2003 and 2006, driven by the adoption of blade and 1U servers. As a result, the traditional rule of thumb for power planning has evolved from "watts per square foot" to "watts per cabinet".

Cooling

High-density servers generate significant heat, creating a major cooling challenge. The guide emphasizes the importance of hot aisle/cold aisle cabinet configurations, as recommended by ASHRAE and ANSI/TIA-942. Key practical measures include:

1. Cabinet Configuration: Arrange cabinets in alternating hot and cold aisles.
2. Blanking Panels: Install blanking panels in every open bay to prevent hot air recirculation.
3. Air Dams: Install air dams to block hot air from slipping around the sides of mounted components.
4. CRAC Placement: Position precision Computer Room Air Conditioners (CRAC) at the ends of hot aisles.

Space Allocation, Cable Management, and Access Floors

• Space Allocation: Support equipment like HVAC, UPS, and generators should ideally be located outside the production floor to free up valuable space.
• Cable Management: Careful planning is needed to avoid blocking airflow, especially under raised floors. Overhead cable management is becoming more common to ensure unrestricted airflow and easier access.
• Access Floors: The choice of access floor (raised floor) is critical for cooling, equipment support, and cable distribution. Factors like seismic requirements, load capacity, and panel strength must be considered.

Section 3: Data Center Infrastructure Considerations

Racks, Cabinets, and Support Infrastructure

This section covers the selection of racks, enclosures, and cable pathways, emphasizing support for climate control, power and cable management, and security. Redundancy and path diversity are critical for achieving high availability, as highlighted by the concept of "five nines" (99.999%) reliability.

Choosing the Appropriate Cabling Media

A key decision is the choice between copper and fiber cabling. The guide provides a balanced analysis:

Copper Considerations:

• The guide notes that ANSI/TIA-942 recommends ANSI/TIA Category 6/ISO Class E as the minimum for data centers, with Category 6A/ISO Class EA recommended for 10GBASE-T.
• Category 5 and 5e are not recommended for new data center installations.
• Copper offers lower initial electronics cost and flexibility for short links.

The Case for Fiber:

• Fiber offers advantages in bandwidth, distance, immunity to EMI/RFI, and space savings.
• Preterminated fiber solutions can provide up to 75% faster installation compared to field-terminated systems.
• Laser optimized 50-micron/ISO OM3 fiber is generally recommended for storage area networks (SANs) and high-bandwidth applications.
• The guide notes that the cost of a high-quality copper channel is now economically equivalent to a fiber solution, making fiber a more compelling choice.

Cable Types and Construction

The guide discusses the importance of cable construction for fire safety:

• Limited Combustible Cable (LCC) offers superior fire and smoke performance compared to standard CM, CMR (riser), or CMP (plenum) cables, making it an attractive choice for data centers.
• Low-Smoke Halogen-Free (LSZH) cables are also specified in many regions to limit toxic fumes and smoke.

Power Cables and Accessories

This section covers the selection of power cables based on:

• NEC and Local Codes: In the U.S., installations must comply with the NEC (NFPA 70) or the Canadian Electrical Code (CSA C22.1).
• Cable Tray Ratings: Cables installed in trays must meet specific fire test requirements (e.g., UL "For CT Use" rating).
• Conductor Sizing: Based on ampacity, voltage drop, and efficiency considerations.
• Stranding: The guide distinguishes between Class B (standard) and Class I (flexible) stranding, noting that Class I has a larger diameter and requires specific "flexible" lugs.
• Backup Systems: It emphasizes the need to integrate primary electrical systems with UPS, battery, and generator backup systems.

Intelligent Infrastructure Management (IIM)

The guide introduces the concept of IIM as a way to manage increasingly complex networks. It notes that manual infrastructure management is insufficient to achieve the goal of high-availability "on demand" networks. IIM systems provide real-time visibility into the physical layer, enabling better asset utilization, business resiliency, and security.

KVM Switches

The guide mentions KVM (Keyboard, Video, Mouse) switches as a tool for managing multiple servers from a single console, saving space and improving operational efficiency in the data center.

Section 4: Best Practices for Data Centers – Standards and Associations

ANSI/TIA-942 (Data Center Standard)

This is the key standard for data center infrastructure. The guide covers its guidance on:

• Topology: Hierarchical star architecture is recommended.
• Hot and Cold Aisles: Minimum aisle widths and layout recommendations for cooling.
• Tier Levels: The Uptime Institute’s Tier Classification (I-IV) is incorporated into the standard, outlining levels of redundancy and fault tolerance.
• Cabling: Recommendations for Category 6 (copper) and laser optimized 50-micron fiber (OM3).

Other Relevant Standards

The guide lists numerous other standards, including:

• IEEE 802.3an (10GBASE-T): The standard for 10 Gigabit Ethernet over copper.
• IEEE 802.3af/at (PoE): Power over Ethernet standards.
• ANSI/TIA-569-B: Pathways and Spaces.
• ANSI/TIA-606-A: Administration (labeling).
• J-STD-607-A: Grounding and Bonding.
• LEED: A green building certification program.

Section 5: Key Considerations for Deploying Data Center Solutions

This final section emphasizes the importance of supply chain management for data center projects. It explains how a total cost of ownership model, considering factors like material management and logistics, can reduce overall project costs and timelines. The guide highlights Anixter’s own supply chain solutions as a means to streamline the procurement and delivery of complex data center infrastructure.

Conclusion: A Trusted Reference for Data Center Design

Anixter’s Data Center Infrastructure Resource Guide is a valuable and practical resource for anyone involved in the design, construction, or management of a data center. By compiling essential information on standards, best practices, and key technologies, the guide provides a solid foundation for making informed decisions that ensure reliability, performance, and scalability. Its systematic approach to topics like cable media selection, power distribution, thermal management, and redundancy helps professionals navigate the complexities of building the nerve centers of the modern economy.

Download the Full Guide

This overview is based on Anixter’s comprehensive guide. The full document provides a much deeper dive into each topic, including more detailed explanations of standards, in-depth analysis of cabling options, and practical guidance on supply chain management for data center projects.

The guide is available to download for free from the provided link:

Download the Data Center Infrastructure Resource Guide (PDF)

Disclaimer: This article provides a summary of a third-party technical publication. While efforts have been made to accurately represent the content, please refer to the official Anixter document for complete technical details. Final design decisions should be made by qualified professionals.