Leviton Online Knowledgebase : Discussion List - Cable Assemblies

Does Leviton offer mode conditioning patch cords?

CommunityAdmin@leviton.com — Fri, 02 Nov 2012 20:39:32 GMT

And what is a mode-conditioning patch cord?

How does contamination insertion loss occur?

CommunityAdmin@leviton.com — Wed, 10 Oct 2012 20:54:29 GMT

How does contamination insertion loss occur?

How does air gap insertion loss occur?

CommunityAdmin@leviton.com — Wed, 10 Oct 2012 20:46:31 GMT

How does a air gap insertion loss occur?

What is the typical color for a Singlemode OS1/OS2 fiber cable?

CommunityAdmin@leviton.com — Wed, 10 Oct 2012 16:41:13 GMT

What is the typical color for a Singlemode OS1/OS2 fiber cable?

What is the typical color for a Multimode OM3 fiber cable?

CommunityAdmin@leviton.com — Wed, 10 Oct 2012 16:35:04 GMT

What is the typical color for a Multimode OM3 fiber cable?

What is the typical color for Multimode OM1 and OM2 fiber cable?

CommunityAdmin@leviton.com — Wed, 10 Oct 2012 16:21:51 GMT

What is the typical color for Multimode OM1 and OM2 fiber cable?

What is the typical color for an Indoor/Outdoor fiber cable for both Multimode and Singlemode fiber?

CommunityAdmin@leviton.com — Wed, 10 Oct 2012 15:59:53 GMT

What is the typical color for an Indoor/Outdoor fiber cable for both Multimode and Singlemode fiber?

When was the first transatlantic fiber optic cable installed?

CommunityAdmin@leviton.com — Tue, 25 Sep 2012 16:26:24 GMT

When was the first transatlantic fiber optic cable installed?

Overcoming OM3 Performance Challenges

CommunityAdmin@leviton.com — Mon, 24 Sep 2012 22:35:54 GMT

For many years 62.5/125 μm (OM1) and conventional 50/125 μm (OM2) multimode optical fiber systems have dominated shorter distance communication applications, such as within a building or on a single-site campus. The fibers easily support applications ranging from 10 Megabit Ethernet (MbE) to Gigabit Ethernet (GbE). Their relatively large core sizes simplify connections and are ideal for use with low cost LED transmitters.

With the advent of 10 Gigabit Ethernet (10GbE), typical in data centers, the physical limitations and properties of multimode fiber are being severely tested. Multimode fiber provides many allowable paths for light to travel down the fiber, and due to intermodal dispersion not all pulses arrive at the destination simultaneously. This characteristic, as well as other issues, ruled out the use of OM1 and OM2 fiber for 10GbE.

To address this, the IEEE created the 10GBASE-S (the S stands for short wavelength) multimode fiber specification with the goal of providing 10GbE operating distances of 300 meters. Laser-optimized OM3 fiber was specified in TIA-492AAAC to support both the IEEE standard and economical vertical cavity surface emitting lasers (VCSELs) that operate at the 850 nm and 1300 nm wavelengths. Fiber that meets the standards delivers an effective modal bandwidth of 2000 MHz*km at the 300 meter distance.

The TIA-568-C.3 standard (Optical Fiber Cabling Components) allows for a maximum 2.6 dB insertion loss with 300-meter OM3 fiber cabling channels. However, manufacturers typically have not had their fiber cabling systems independently tested, and as a result, designers

and managers of OM3 fiber networks are uncertain what the true parameters are for premises applications.

Insertion loss for OM3 cable is typically 3.0 dB per kilometer. The TIA standard allows 0.75 dB insertion loss per connector mated pair. For example, a 300-meter channel configuration with six mated pairs could have a maximum insertion loss of 3.9 dB, well above the 2.6 dB limit. Undoubtedly, this explains why some vendors have recommended that users stay well below the 300-meter length limit. Others have addressed this possibility by offering low-loss cassettes, albeit at a

considerable cost premium – approximately 50%. Putting the Latest Generation of Fiber to the Test How much headroom does a 50/125 μm laser optimized

fiber system actually provide relative to the specification? To address this question, Leviton contracted with Intertek Group PLC (ETL) to test Leviton’s OM3 fiber system, including MTP trunk cables, MTP-LC cassettes and harnesses, MTP adapter brackets, and LC-LC OM3 patch cords. All channels were set up and bi-directionally tested with

readings measured against maximum allowable insertion loss as specified in TIA-568-C.3, using Annex E guidelines. 2 LEVITON.COM/CROSSTALK

Overcoming OM3 Challenges continued from pg. 1

It is clear from these tests (see channel configurations and test results below) that 10GbE specifications can be met without the additional costs of low-loss cassettes. These tests, the first known to provide independent verification of OM3 fiber channel performance, show substantial margin under TIA insertion loss limits for 10GbE using Leviton's standard cassettes. With the assurance of these results, network designers have the freedom to utilize the complete 10GBASE-S standard including distances up to 300 meters and the maximum number of specified connectors. In addition, the test results show that the latest generation OM3 fiber systems provide a solid foundation for future installations of 40GbE and 100GbE. The IEEE approved the 802.3ba standard in June 2010; it specifies a maximum insertion loss of 1.9 dB for

40/100GbE using OM3 cabling. The systems tested here are already right on the border of meeting that specification, indicating that organizations will be able to upgrade with either no or very limited system changes.

Demand Grows for Better Fiber Network Security

CommunityAdmin@leviton.com — Fri, 21 Sep 2012 18:36:29 GMT

As IT plays an increasingly significant role in business and government operations, protecting information has become critical. Every year organizations spend more time and resources improving data security, from cameras to firewalls. And while we often imagine security threats coming from cyber hackers and outside entities, many security breaches come

from internal personnel.

In fact, unauthorized internal access to servers and workstations — whether it be from inadvertent changes or administrators and personnel with unknown agendas — is among the most common threat scenarios. The 2008 CSI Computer Crime and Security Survey reports that insider abuse ranks among the top two security concerns, with 44% of security professionals citing the threat. To help limit physical access to networks, more companies are installing secure connectivity systems, including copper and fiber connectors that can only plug into matching color ports. Some of these extra security steps are mandated in environments with sensitive data, such as WAN links, data center core switch links, remote medical links, municipal 911 circuits, and Department of Defense SIPRNet links.

Focus on Fiber

One common solution for protecting fiber networks is a keyed LC system. The LC connector is a popular choice over other small form factor options, and LC connectors are common in networks requiring Gigabit speeds, making them ubiquitous in many data centers. Conventional keyed LC solutions provide a base level of security: only matching color connectors and adapters will interconnect. Segregating different networks through color-coding is commonly found in government networks like SIPRNet and JWICS. However, the connectors in these systems can still be removed by hand.

Leviton addresses this gap in security with its new Secure Keyed LC Fiber System. The system allows users to lock out ports, lock circuits for disconnect, and keeps connections from being removed by hand. When using the Secure LC patch cords, trunks, and harnesses, users can only remove a keyed connector with a matching color keyed extraction tool. The tools allow a CIO or IT manager to control administration ofthe network, limit the levels of security in a secure network, or limit the MAC ability to the circuit owner in a cafeteria network.

The Secure LC’s “lock-out” capabilities protect unused ports from unauthorized insertion of a cable assembly or connector.

Locking Port Protection Plugs can be inserted into unused LC ports, and just as with the cable assemblies, only those operators with a matching color keyed extraction tool can open those ports. Plus, the system includes dust caps to protect connectors upon removal from a port.

Keeping Costs Down

End users who invest in a traditional keyed LC system may face steep costs, as many of them require purchasing not only

connectors or assemblies but adapter modules and mounting hardware for the “keyed” features to work. Unlike these conventional systems, Leviton makes security upgrades easy on the wallet: the locking technology built into the body of Leviton’s secure LC assemblies do not require replacing existing connectors, adapters, or wallplates — they connect to any industry standard LC duplex or quad adapter. This means that those with existing LC networks can retrofit their system without having to rebuild it.

To learn about Leviton’s Secure Keyed LC Fiber System, go to

Leviton.com/secureLC, where you’ll find a brochure, specification

sheets, and a demonstration video.

What five factors must you address when expanding an existing data center?

CommunityAdmin@leviton.com — Fri, 21 Sep 2012 17:35:51 GMT

What five factors must you address when expanding an existing data center?