By: John Shepler

As the demand for more bandwidth increases, so do LAN, MAN, and WAN speeds. This puts pressure on both copper and fiber-based telecommunication networks to upgrade their speeds more frequently. Let’s examine the options for both traditional TDM (Time Division Multiplexing) and IP (Internet Protocol) networks.

Traditional Copper Telecom Lines

Copper wiring has been the foundation of electronic communication since the telegraph and telephone networks. While the telegraph is obsolete, the telephone is transitioning technologically, with voice becoming a converged network service. Even cellular phones will soon move away from voice-only channels to data integration with the implementation of 4G LTE wireless technology.

Analog POTS (Plain Old Telephone Service) is nearing its end. However, its infrastructure of twisted-pair copper lines connecting nearly every building, both commercial and residential, will remain for decades to come. This copper infrastructure retains value because it can transmit digital signals as well as analog.

Digital T1 Lines

The earliest digital protocol for data transmission over twisted-pair copper (excluding telegraph) is the T1 line, which is still widely used today. It is used for telephone trunking, point-to-point data transmission, and dedicated Internet connections. T1 was initially developed to transmit multiple phone conversations digitally over existing telephone lines. Using signal regenerators to clean up the signal every 6,000 feet, T1 can transport service across long distances. You can get T1 service practically anywhere you can get landline phone service. Its 1.5 Mbps bandwidth is its only drawback.

While 1.5 Mbps was once considered broadband, it is no longer sufficient for anything beyond PBX telephony, casual Web browsing, email, and point-of-sale credit card verification. This bandwidth is comparable to 3G wireless. Wireless technology is quickly transitioning to 4G, which offers significantly faster speeds. Similarly, wired services are shifting to a minimum requirement of 10 or 15 Mbps.

Bonding T1 Lines & Ethernet over Copper

By combining the bandwidth of multiple T1 lines into a single, larger service level, T1 is extending its useful life. This is practical up to 10 or 12 Mbps, but beyond that, it becomes too costly and challenging to locate available bundles of unused copper pairs. A new technology that can extract more bandwidth from the same copper is required.

Ethernet over Copper (EoC) is the name given to this technology. Ethernet serves the same purpose as T1 but differs in how bits are arranged on the line. It makes use of the same copper pair cabling, with multiple pairs bonded together to boost bandwidth. The distinctions are that EoC is available in increments ranging from 3 to 45 Mbps and that its range is limited. High speeds are possible near central offices. EoC service may be unavailable a few miles away. Different service levels are possible in between.

Data transmission over copper pair wiring has progressed significantly, with some installations now supporting bandwidths of up to 100 or 200 Mbps. These are, however, uncommon. Cable broadband, which employs coaxial copper cables and a modulation scheme known as DOCSIS 3, can reliably deliver 100 Mbps or more bandwidth. Even 1 Gbps is possible, though not widely available. Another service, DS3 or T3, provides 45 Mbps over two coaxial lines, where available.

Fiber Optic Services for Unlimited Bandwidth

Fiber optic cabling is the way to go for higher bandwidths. Fiber bandwidth is virtually limitless, especially when wavelengths are combined to create extremely large services. Fiber, like copper, has a long history and a more recent technical approach.

SONET (Synchronous Optical Network), a telephony standard, is the foundation of traditional fiber optic service. OC-3 at 155 Mbps, OC-12 at 622 Mbps, and OC-48 at 2.4 Gbps are common service levels. Higher levels include 10 Gbps and 40 Gbps.

Ethernet over Fiber (EoF) is a Carrier Ethernet service similar to EoC, but it uses fiber rather than copper transmission. Fiber Ethernet is very cost-effective and widely available, with speeds ranging from 10 Mbps to 10 Gbps. The most common service levels today are 100 Mbps Fast Ethernet and 1,000 Mbps Gigabit Ethernet (GigE). Businesses in some areas have access to 100 Gbps service.

Wavelengths Options

Fiber has another advantage over copper in that it supports multiple 10 Gbps wavelengths via WDM (Wavelength Division Multiplexing). This means that multiple protocols can be run on separate wavelengths within the same fiber strand. This provides financial institutions and other organizations with demanding applications with a high level of flexibility.

As you can see, there are a plethora of copper and fiber transmission options available right now. The best option for your organization will be determined by application requirements, scale, and budget. You’ll most likely have to choose from a variety of technologies and vendors.