Structured Cabling: Cabling a Data Center

A data center cabling design is different from normal commercial building cabling design. Most important areas to be addressed in data center are as follows.

Manage higher densities: Data center typically will have very high fiber density and this should be scalable and easy to maintain.
Cable management: Higher densities lead to difficulty in cable management and moves adds & changes become difficult. Proper cable management with bend radius protection is required in a data center.
Heat control: Poor airflow is a major concern in data centers. Proper cable management addresses this.

Most important is the "uptime". Select a cabling solution that is reliable and allows you to scale up to Tier-4 reliability level.

CASE STUDY: IT Company's Data Center Installation
A leading IT company needed a standard network cabling system for its Center of Excellence (CoE) in Bangalore. The CoE houses 32 offshore development centers (ODC) and comprises a library, conference rooms, performance laboratories, usability laboratories, and a concept center for product display and simulation. The center focuses on the development of financial products

Challenges
The Bangalore-based CoE required a network management system and process that was easy and efficient. The company also wanted to avoid the hassles in troubleshooting that arose due to the lack of proper documentation and labeling. Lack of proper documentation and labeling meant that when there did arise a need to troubleshoot, the company's IT team would be drilling holes across the facility to first identify the origin of the problem before actually solving it.

IT company needed the best passive components for its COE. It required a cabling system with network speeds up to 1 Gb Ethernet for horizontal connectivity, and 10 Gb Ethernet for backbone connectivity and its data center.

Solution
IT company zeroed in on a standard network cabling system and passive components from ADC Krone that included Category5 cabling, Category6 cabling, OM3 laser optimized fiber, KM8 Category 6 jacks, CopperTen, CopperTen jacks, patch panels and patch cords. IT company also opted for colored cabling components that helped IT company employees easily identify cables for troubleshooting.

ADC Krone worked alongside CMC, a systems integrator and IT company' subsidiary company. IT company opted for Category 5E cabling for voice connectivity and Category 6 cabling for data connectivity. For horizontal data cabling ADC Krone's KM8 Category 6 jack was used in conjunction with Cat6 cables and patch cords. The desired result was to offer maximum benefit for data connectivity; to eliminate installation errors such as excess untwist of pairs, separation between conductors, etc; while providing consistent performance across the network.

For its backbone connectivity, IT company selected OM3 laser optimized fiber. This multimode fiber can handle 10 Gb Ethernet. For its data center, the core of its network, IT company reserved ADC Krone's augmented Category 6 solution 'CopperTen'. The CopperTen cables coupled with the CopperTen jacks, patch panels and patch cords, offers excellent results even at the high frequency 10G transmission where alien cross talk is a major concern.

Since troubleshooting was the other concern, IT company wanted different colored cables for quick identification. ADC Krone provided labeled components and cables in different colors which made for easy identification of the data, voice and redundant ports at each node as well as throughout the facility. This allowed IT company' IT team to cite problems quickly and implement a speedy solution.

Benefits
The most important benefit from the installation of ADC Krone's products was the establishment of a robust structured network cabling system. The future proof products and solutions from ADC Krone eliminated, for IT company, the need to re-cable in the future. Furthermore, the color-coded cables from ADC Krone ensured efficient manageability of the network infrastructure while complimenting the architecture of the facility.

Cabling may be copper (UTP/ScTP) or fiber (SM/MM) which will depend on the interface of the equipment to which it is to connect. Typical practices allow for dark fiber (unused strands) to be run along with the active fiber. Equipment may be active or passive.

Cabling Pathways
Data centers contain highly consolidated networks and equipment. This high consolidation requires high density cabling systems. Cabling pathways in the data center generally consist of a combination of access under a raised flooring system and overhead cable tray. Raised floors provide the benefit of aesthetic pleasure along with heat management and easy access to the hidden cables.

Higher density cabling components can help reduce the amount of floor space, rack space and associated costs

Cables under a raised floor should be run in raceways (cabling channels) to protect them from power cables, security devices and fire suppression systems which may be run in the same environment. Power cables can be run either in conduit or in power raceways and should respect the minimum distances outlined in industry standard specifications. Raceways aid in the distribution of cool air, facilitate future cable moves, adds, changes and ensure cable performance.

The fiber cabling pathway and management in the data center should be provided by a dedicated duct system. This provides a safe and protective method for routing and storing optical fiber patchcords, pigtails and riser cables among fiber distribution frames, panels, splice cabinets and termination equipment. Fiber carries different stress and bends radius requirements than copper due to the fact that it carries light rather than electrical signals. Planning is required to assure that proper space allowances are provided.

Cabling Components
One needs to watch out for factors that can make or break the start up of a data center. The traditional cabling process of pulling in cables, connecting the cables, populating patch panels, testing and troubleshooting introduces delays and uncertainties.

CASE STUDY: Campus Cabling Installation at Manipal University
Manipal University formerly known as Manipal Academy of Higher Education (MAHE) has been imparting world class education for over 53 years. It is the learning place for students from more than 51 countries. It houses the best library and finest anatomy museums in the world what more � it has a fully networked campus. The entire campus has more than 20 blocks including Kasturba Medical College & Hospital, MIT, TAPMI, ICAS, Hostels and the Old MAHE building

Challenges
Managing assets across a large campus was similar to managing a metropolitan sized network. There was a need for an intranet facility to facilitate the faculty and students to access information and to coordinate work processes. There was an urgent requirement for adding flexibility to performance and manageability. Only a structured cable system could provide the desired reliability of network performance in a uniformed manner.

Solution
The University chose fiber cabling solution from D-link. The Digilink multimode fiber runs through Kasturba Medical College & Hospital, MIT, TAPMI, ICAS, Hostels and the Old MAHE building. All these blocks are connected to the data center using D-link's Digilink single mode fiber and for the LAN has been cabled using D-link's Digilink Cat 6 UTP cables providing more than 5,000 nodes including the earlier Cat 5e network. More than 70% of the LAN network is of Cat 6 UTP.

Benefits
Over 20 buildings within the campus were connected with a structured cable system that enabled high performance, manageability and provided good reliability. The University students and faculty can now interact through virtual classrooms. Furthermore enterprise applications, e-learning tools and multimedia applications were all routed through the SCS system throughout the campus.

With the hospital also on the network, it made information like MRI scans, reports, digital films, etc available to doctors and medical students anywhere anytime.

Since future rack placement is typically determined in advance, trunk cables of predetermined lengths can be ordered in advance and stored until needed to enable cost-effective installation in phases and easy upgrades with minimal downtime.

The traditional cabling process of pulling in cables, connecting cables, populating patch panels, testing and troubleshooting introduces delays and uncertainties

In addition, traditional cabling components do not provide high-density options for space savings. Selecting MPO fiber optic and MRJ 21 copper pre-terminated trunk cables, breakout cassettes and cable assemblies is an ideal solution to meeting data center objectives.

Most network equipment is not equipped with an MPO interface, but rather with existing MT-RJ, LC, ST or SC type interfaces. Modular cassettes transition the 12 fibers of an MPO connector by routing each fiber of the MPO connection on the back of the cassette to the appropriate interface port on the front. Cassettes fit into existing patch panels and enclosures, and standard patch cords are used to connect ports on the front of the cassette to the network equipment interfaces. MPO cassettes can also be purchased and stored until needed.

MRJ 21 high-density copper connectivity solutions also include pre-terminated and tested trunk cables. The trunk cables are high performance 25-pair cables terminated with MRJ 21 connectors, which offer much higher port density than the common RJ45 interface. The MRJ 21 connector plugs into the back of high-density RJ45 panel-mounted cassettes or into a fixed-port and straight 1U patch panels or into equipment with the MRJ 21 connector interface.

The modular set up of eight pluggable MRJ 21 connections instead of 48 individual RJ45 terminations significantly reduces on-site labor, increases system uptime, and offers better cabling efficiencies. Connecting equipment using the MRJ 21 solution is about six times faster than with standard four-pair wiring.

Cooling is a very real concern in data centers, with dense copper cabling this is one reason why fiber is gaining popularity

Easy Steps to Implement Structured Cabling

Step 1 Scalability: Choose a cabling standard that ensures upscaling easily. Identify bandwidth requirements; ask what applications will you use on the network, now and in future.
Step 2 Planning: The range and layout of your network should be chalked out in advance so that you can plan optimal cable layouts.
Step 3 Flexibility: Assess the flexibility of your network in terms of adding or changing network nodes.
Step 4 Cost: Cabling will be a one-time investment and probably 7-8% of your total infrastructure budget. So don't skimp on cabling costs just because you have spent heavily on other aspects of infrastructure (like storage, servers or switches).
Step 5 Vendor Choice: Go for a vendor that preferably has manufacturing expertise and stable R&D roadmap. Choose a certified system integrator who will adhere to standards strictly.

As owners and operators strive to meet their cabling objectives, MPO fiber optic and MRJ 21 copper connectivity solutions are ideal components for providing reliable transmission, reduced real estate costs, quick deployment and upgrades, low investment and long-term cost effectiveness.

Cabling is often overlooked or taken for granted, but even electronics vendors capturing the majority of the data center market will be the first to say that all of their devices are useless if the cabling is incapable of supporting the applications. Understanding the data center standards, identifying cabling objectives and choosing the right components will go a long way towards ensuring reliable performance and operation of a data center. It is a decision that can save time, money and frustration-now and tomorrow.

Malovika Rao
malovikar@cybermedia.co.in