Maximizing use of existing cabling saves time, money and headaches

New media converters and extenders are available for most cable situations

This vendor-written tech primer has been edited by Network World to eliminate product promotion, but readers should note it will likely favor the submitter’s approach.

Network advances often require cable upgrades, but rewiring takes time and money.  Often the existing cable can be leveraged, or the extent of the upgrade minimized, using ]media converters, one of the least glamorous yet most common and perhaps most versatile tools in a network manager’s toolbox.

New media converters and extenders are available that support Power-over-Ethernet (PoE and PoE+) and legacy cabling types such as coax and 2-wire. These devices enable increased utilization of existing network cabling while upgrading network performance.

Let’s look at some of the most popular cabling types with regard to when cabling should be replaced versus when changes can be minimized with the use of media converters.

* Coax. Many organizations (such as schools or businesses) that were once pioneers in video conferencing or were early adopters of analog security systems may still have this cable in the walls. If the coax is no longer being used for these systems, it is typically abandoned but not removed because the cost and disruption makes it easier to just leave it in place. By using a coax-Ethernet media converter offering PoE/PoE+, it’s possible to resurrect this old cable for re-use with up to 1Gbps Ethernet connections. Generally, this makes it more cost effective to upgrade analog security cameras to IP-based digital cameras or to connect a conference room to a backbone network.

* CAT3 and other 2-wire cabling.  The IP telephony revolution has left many organizations with a lot of unused copper phone cable and early 10Base-T Ethernet network cable. But it could be re-used to provide Ethernet connectivity to remote areas of the building via media converters and extenders. Similarly, in outdoor applications where 2-wire cable may have been used for call boxes or other applications, it could now be used to power IP-devices like wireless access points or security cameras.

* CAT5/CAT5e UTP. Category 5/5e UTP cabling (CAT5) is commonplace as it was predominantly used in structured cabling for computer networks before the advent of CAT6. CAT5/5e cabling is rated at 100MHz and easily supports Fast Ethernet for up to 100 meters. While newer CAT5e cabling can reach gigabit speeds for shorter distances, supporting new NBase-T (2.5Gbps or 5Gbps) will be difficult. But the use of media converters allows network managers to extend the distance of a Gigabit Ethernet connection over CAT5, upgrade certain links to CAT6 or even to fiber-optic cable if necessary to support the bandwidth or distance needs.

* CAT6 UTP. Category 6 unshielded twisted pair (CAT6 UTP) is primarily used in greenfield network implementations or in newer cable upgrade projects. CAT6 can handle up to 1 Gigabit per second of data, with maximum transmission distance of 100 meters. CAT6A, however, can maintain 10Gbps speeds across the same distance. Only in the event of a very long cable run or when upgrading to 10/40Gbps Ethernet would it make sense to upgrade from CAT6 to fiber-optic cabling. In this application, copper to fiber media converters make sense if only a few connections need to be upgraded for distance or bandwidth needs. This makes it possible keep the existing switches in place while upgrading only the minimum required links.

* Multimode fiber. Multimode fiber is often used in campus backbone networks where data must travel distances longer than 100 meters, but doesn’t justify the installation of single mode fiber. With data speeds continuing to increase, multimode fiber is starting to reach distance limitations. At 10Gbps, for example, data can travel up to a maximum of 300 meters on multimode cable. However, even up to 40Gbps, it isn’t necessary to replace multimode fiber because media converters or optical repeaters can re-amplify, reshape and retime (3R) the light signals, allowing data to be repeated for much longer distances.

* Single mode fiber. Single mode fiber is often used for backbone networks and is the longest distance, highest bandwidth cable type on the market, capable of data transmissions of up to 30 kilometers. Although single mode fiber is expensive, it is the highest quality media available, thus there are very few applications where a network is better off with another cable type.

Replacing cabling is sometimes required to support network changes, but it always adds cost and time to the upgrade. When deciding between upgrading the cabling infrastructure or trying to leverage existing cabling by using media converters or repeaters, it is most important to know what is already installed, what’s currently in use and, if possible, where the cabling is located.

Learn more at Transition Networks.

Join the Network World communities on Facebook and LinkedIn to comment on topics that are top of mind.

Copyright © 2017 IDG Communications, Inc.

SD-WAN buyers guide: Key questions to ask vendors (and yourself)