For many years and by many people, fibre optic cabling has been viewed as the ultimate network cabling infrastructure with respect to performance and security. This viewpoint is indeed true when applied to certain types of fibre, BUT NOT ALL.

Many network managers are not aware that there are different types of fibre optic cable, let alone the fact that some fibre optic cables are more limited than others. Essentially there are two types of fibre and then within the two types there are more variations again.

Multimode is by far the most commonly deployed fibre optic cable for building and campus network systems. While the second type of fibre Singlemode is by far the most commonly deployed fibre for WAN (Wide area network) or Carrier (ie Telstra, Opts etc) communications environment.

While Singlemode fibre will in fact enable you to travel 10's of kilometers. Obviously this example does not present any real problem for most building or campus environments, but the situation becomes more critical as the bandwidth increases. Let us take a further example of a link requiring bandwidth of 1000Mb (Gigabit Ethernet), which is a popular backbone standard for many environments today.

At this level, your typical Multimode cable may not be able to provide service beyond 280m, while Singlemode will allow you to extend kilometers. Again if we move to the next generation of backbone bandwidth, 10,000Mb (10 Gigabit Ethernet), the situation worsens further. Where Singlemode will provide kilometers of link distance, Multimode fibre might run out of puff in less than 100m!