How to route patch cords

Simple guidelines can help gain efficiency in the telecom room.

By Dennis Mazaris, RCDD, Concert Technologies

Problem

When someone installs a patch cord in a management system, typically little if any attention is paid to patch-cord routing. After all, patching is by its nature a task to be performed quickly. This causes disorganization of the patch-cord management system and decreases the performance of the network by increasing the time needed to identify and rectify faults.

Solution

Establish a simple guideline that will provide the support needed to understand and teach someone how to route patch cords in the most efficient manner possible.

Procedure

Divide the equipment rack into two equal vertical sections, left and right.

Route patch cords through horizontal and vertical managers. When routing a patch cord, you must always route it in a path that will eliminate all of the patch-cord slack. If slack is present after your first attempt at routing, you may reroute or apply patch-cord adjusters to eliminate the slack.

Routing and patching should be performed in one section at a time. Crossing a section should only occur when you need to eliminate patch-cord slack.

If patch-cord slack is present after rerouting, apply adjusters. If the adjuster can be applied as shown in the illustration or within a single section, then route the patch cord appropriately to accomplish this task. Try to avoid crossing a section.

The key to patch-cord routing is to have an adequate number of horizontal and vertical managers in your system and to eliminate slack in each cord by adjusting your managers and patch-cord adjusters.

In the illustration, there is patch-cord slack in the lower left side of the equipment rack. This patch cord should have patch-cord adjusters applied to eliminate slack or, as shown on the right side of the rack, the patch cord must be rerouted through horizontal and vertical managers to eliminate slack. Trying to reroute slack through managers as shown in the right side of the rack may still result in patch-cord slack. When this occurs, apply patch-cord adjusters to eliminate slack.

Migrating to higher speeds on your network with OM3 and OM4 connectivity

Cabling infrastructure installed today must provide scalability to accommodate tomorrow's needs.

BY DAVID KOZISCHEK AND DOUG COLEMAN, CORNING CABLE SYSTEMS

With the continued requirement for expansion and scalability in the data center, cabling infrastructures must provide reliability, manageability and flexibility. Deployment of an optical connectivity solution allows for an infrastructure that meets these requirements for current and future data rates. A key factor when choosing the type of optical connectivity is scalability. Scalability refers to not only the physical expansion of the data center with respect to additional servers, switches or storage devices, but also to the scalability of the infrastructure to support a migration path for increasing data rates. As technology evolves and standards are completed to define data rates such as 40- and 100-Gbit Ethernet, 32-Gbit and higher-speed Fibre Channel, and 40-Gbit and higher-speed InfiniBand, the cabling infrastructures installed today must provide scalability to accommodate the need for more bandwidth in support of future applications.

850-nm Ethernet distance (in meters)
	1G	10G	40G	100G
OM3	1000	300	100	100
OM4	1000	550	150	150

One- and 10-Gbit/sec data rates are not adequate to meet the future needs of high-bandwidth applications. The requirement for higher data rates is being driven by many factors. Switching and routing, virtualization, convergence and high-performance computing environments are examples of where these higher network speeds will be required within the data center environment. Additionally, Internet exchanges and service provider peering points and high-bandwidth applications, such as video-on-demand, will drive the need for a migration from 10- to 40- and 100-Gbit interfaces.

IEEE 802.3ba ratified

The Institute of Electrical and Electronics Engineers (IEEE; www.ieee.org) 802.3ba 40G/100G Ethernet standard was ratified in June 2010. The standard provides detailed guidance for 40/100G transmission with multimode and singlemode fibers. The standard does not have guidance for Category-based unshielded twisted-pair or shielded twisted-pair copper cable. OM3 and OM4 are the only multimode fibers included in the standard.

	IEEE	Designation	Mbits/sec	Fiber type	Number of fibers	Maximum link length (in meters)	Maximum channel insertion loss (in dB)
10-Gbit Ethernet	802.3ae	10GBase-SR	10,000	OM3	2	300	2.6
40-Gbit Ethernet	P802.3ba	40GBase-SR4	40,000	OM3	8	100	1.9
40-Gbit Ethernet	P802.3ba	40GBase-SR4	40,000	OM4	8	150	1.5
100-Gbit Ethernet	P803.2ba	100GBase-SR10	100,000	OM3	20	100	1.5
100-Gbit Ethernet	P803.2ba	100GBase-SR10	100,000	OM4	20	150	1.5