EMI - fiber vs STP?

EMI - fiber vs STP?

Hello, im a little confused with my **** study guide....and real life exp.....

basically i want to know is what would be cisco looking for if this question comes up?

From my **** study guide, says the following:

"Optical-Fiber optic cables are less susceptible than metal cables to interference."

"STP- .....The extra covering in shielded twisted pair wiring protects the transmission line from electromagnetic interference. consider the use of STP when network cabling must be run closely to items that might create EMI, such as motors of flurescent lights."

From my telecom cable humping days, my instinct is to immediately say that fiber is the way to go over STP to avoid EMI, i know that STP is ok for blocking EMI but its not "immune" so to speak for fiber........but im not so sure after reading this, would cisco lean towards STP?

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Comments

kafifi13

Is this from Cisco Press? From my experiance and reading it is obvious that Fiber is the way to go. Problem is it's too expensive so maybe they mean STP compaired to UTP for extra protection. Regardless they still recommend UTP for it's flexability.

Netstudent

Ya that would definately depend on how much money an organization had to spend, as well as how critical that data is that would be crossing that line. It would also depend on how much machinery and other EMI emitting devices were in the facility.

Reagrdless, if the question comes up, I would choose Fiber over STP. Unless the question states that the company is broke.

markieman31

Agreed with Netstudent. EMI (Electro magnetic interference). Fiber uses light, not electricity to transmit data, therefore it is completely immune to EMI. STP is still copper cabling and still uses electricity to transmit its data. Even though it is shielded to help prevent EMI, its is not immune to it like fiber is. If the question asks for the type of cable that is immune to EMI, choose fiber. If it gives a scenario, you'll have to figure out what they are looking for to meet the needs of the situation.

phatsoundz

markieman31 wrote:

Agreed with Netstudent. EMI (Electro magnetic interference). Fiber uses light, not electricity to transmit data, therefore it is completely immune to EMI. STP is still copper cabling and still uses electricity to transmit its data. Even though it is shielded to help prevent EMI, its is not immune to it like fiber is. If the question asks for the type of cable that is immune to EMI, choose fiber. If it gives a scenario, you'll have to figure out what they are looking for to meet the needs of the situation.

Good points everyone, I believe too That Fiber is the way to go....unless $ is a concern.