UTP vs. STPThe future is shielded

March 2010

Content

Introduction

Performance Mythbusting

Conclusion

Where The Discussion Started

1. IEEE 802.3an (10GB Ethernet) is the first application standard confirming

that for 10GBE STP performs better than UTP !!!

2. The reason for the limited UTP performance with 10GBE is EMC

Introduction

What is EMC ?

• Electromagnetic compatibility describes the capability of a

device, system or installation to work free of any

interferences in its electromagnetic environment without

impairing the functionality of other installations. Hence,

electromagnetic interference caused by any such installation

must be limited. In order to operate properly, said installation

must also be immune to any interference typically occurring

in its environment

• It is the duty of the enduser to ensure the proper EMC

functionality if his IT systems

Introduction

EMC with 10GBE / Cat. 6A

• 10GBE is very prone to radiation and immunity.

Why ?– 10 Gb/s protocol has a very low signal level

– Our environment is transmitting a lot of noise

– The system is disturbing itself

BlitzstromableiterParallel geführte Leitungen

Leiterschleife

Bild 6: Elektromagnetischer Impuls (Obo Bettermann)

0V

+260mV

- 260mV

100BASE-TX 1000BASE-T10GBASE-T

MLT-3 PAM 5

1mV

DSQ128

noise

40mV

ANEXT

Introduction

Cabling Standard Reaction

• 10 Gb/s Ethernet requires improved Alien Crosstalk and EMC

behavior

• ISO/IEC 11801 amendments 1+2 define Alien Crosstalk

parameters for Class EA / Cat.6A and higher in order to cover the

disturbance from the system itself

• ISO/IEC 14763-2 / EN 50173-1 define the MICE table specifying– Environments classes

– Test parameters and procedures

– Electromagnetic Specifications cover EMC

• MICE environments are mandatory for cabling systems

Introduction

MICE specification for EMC

(ISO/IEC 11801 ed. 2.1)

ISO/IEC 11801

ISO/IEC 14763-2

Introduction

MICE specification

E3E2E1Electromagnetic rating

C3C2C1Climatic

I3I2I1Ingress rating

M3M2M1Mechanical rating

Level 3Level 2Level 1Requirement

• Level 1 is a office environment with low impact

• Level 2 is a office/ enterprise building environment with medium impact

• Level 3 is a industrial environment with high impact

• Important: For some customer groups (hospitals, airports) may a

combination of different classes possible ( M1,I2; C2, E3))

EM

C

Introduction

MICE specification for EMCIntroduction

UTP vs. STP

Performance

Independent Study

Independent 3rd Party Study

• Objectives:

• Qualification of UTP &STP Class EA systems

• Radiation testing

• Live 10GBASE-T Application testing

• MICE environments applications

• Practical testing

• Investigating the myth about

STP systems

• Study done from 06/2008 - 06/2009

at GHMT AG, Germany

• All tests done according international

standards in an EMC chamber

Unique

Performance

Unique

Unique

Unique

Who is GHMT AG ?

• Founded 1992 in Bexbach, Germany

• Independent test laboratory according to ISO/IEC 17025

(first lab accredited in Europe back in 2000)

• One of the 2 leading cabling test labs in Europe

• Strong expertise in

– Cabling & Systems

– EMC analysis & concepts

– Wireless applications

Performance

10GBASE-T live Test SetupPerformance

Qualification Testing

The Qualification

• 3 UTP systems Class EA

• 3 STP systems Class EA– F/UTP

– S/FTP (standard)

– S/FTP (high end)

• The six systems were technically

up to date and sourced from

market leading companies

• Qualification Criteria:

ISO/IEC 11801 Class EA channel

Performance

Qualification Results

• UTP Class EA systems perform well for “In-Channel” parameters like NEXT, RL etc. but 2 out of 3 clearly failed in achieving the Alien Crosstalk requirements (see red mark)

• STP Class EA Systems show much better Alien Crosstalk behaviour because of much higher coupling attenuation (see green mark)

• Conclusion: Twist-only noise suppression is very limited in achieving ANEXT requirements for 10Gb/s

• Cut: Because of insufficient ANEXT behaviour, system 00 has been excluded from the study

Performance

Study Results

EN 55022 / FCC part 15 - Radiation

• 10 GBASE-T shows higher radiation compared to 1 Gb/s

Performance

EN 55022 / FCC part 15 - Radiation

• Comparison of both technologies – UTP radiates much more

Performance

Immunity Testing according MICE I

Conducted High Frequency

• Test according IEC-EN 61000-4-3 to determinesystem immunity against radiated electromagneticfields. Simulates potential sources of disturbancee.g.

• Mobile radio installations, phones, walkie-talkiesand local radio or TV broadcasting stations

Radiated High Frequency

• Test according IEC-EN 61000-4-6 to determinesystem îmmunity against conducted electromagnaticfields. Simulates potential sources of disturbancee.g.

• Local radio or TV broadcasting stations

• Walkie-talkies. ISM devices, etc.

Performance

Practical Test: Mobile Phones

• Cabling systems have been tested with real practical disturbers

( Mobile Phones and Walkie Talkie)

• 10GBASE-T data traffic was monitored while disturbers have been

active

• 10GBASE-T data transfer on U/UTP systems data has been

impacted heavily or transfer stopped completely!

�����������Phones

Syste

m 01

Syste

m 02

System

03

System

04

System

05

Walkie

/Talkie ���� ���� � � �

Performance

Immunity Testing according MICE II

Electrostatic discharge

Magnetic Field

Fast Transients/Burst

Test according IEC-EN 61000-4-2 to

determine system immunity against

Electrostatic discharge (ESD)

caused by:

• low relative humidity

• low-conductivity floor coverings

• operator clothing made of vinyl fibres

Test according IEC-EN 61000-4-4 to

determine system immunity against

fast transient electrical disturbances

as generated by transient switching.

– Cut-off of inductive loads

– Relay contact chatter

– Powering of fluorescent lamps

Test according IEC-EN 61000-4-8 to

determine system immunity against

magnetic fields with power

frequencies (50/60 Hz). Simulates

potential sources of disturbance e.g.

– Currents in lines and busbars

– Transformers

– Low-voltage main distributors

Practical Test: Fluorescent LampsPerformance

System 01 System 02 System 03 System 04 System 05

Fluorescence

Lamp ���� ���� � � �

• 10GBASE-T data transfer stopped completely

or was heavily disturbed with U/UTP systems

when distance from cabling to lamp was < 0,5

m

• The same effect could be observed when lamp

has been switched on/off and distance lamp-

cabling was > 0,5 m

• No effect on STP Cabling

Practical Test: Fluorescent LampsPerformance

• Separation distance

to power cables

• Distances between

0-50 cm

• Simulation of

common installation

practice with burst

placement on power

cables

Practical Test:

Distance to Power CablePerformance

• U/UTP systems need as a minimum 30 cm distance to power cables

• STP systems have no limitations

Practical Test: Fast Transients Separation Distance to Power Cable

Performance

Data impact of separation distance

• What happens with my data when those effects occur ?

E1

Performance

Study Conclusion

Test Result SummaryPerformance

10GBASE-T is very noise sensitive

ANEXT

• Self disturbanceVery sensitive signal to noise ratio

Performance

Noise Immunity = Better PerformancePerformance

Conclusion: STP is betterPerformance

For more Details: www.UTP-vs-STP.com

UTP vs. STP

Independent Study

Mythbusting

What is Mythbusting ?

• Although there are several evidences showing

the superiority of STP systems, there are still a

lot of concerns in the market place

• These concerns mainly exist because of

– the “fear-making” arguments (myths; fairy tales)

spread by UTP suppliers

– the lack of knowledge

• Let’s have a look …

Mythbusting

The Fairy Tales

• STP systems act like an antenna and radiate

• STP system need to be grounded on both sides

• STP requires more complex earthing and bonding

• STP systems have ground loops and current on the screen

• STP has a lot of installation disadvantages

(speed/space/screen)

Mythbusting

Antenna

Effect

Radiation

Antenna effect

• The Myth:A shielded system radiates electromagnetic waves,

especially when it is grounded on one side only

Mythbusting

EN 55022 / FCC part 15 - Radiation

• The Truth: STP radiates less than UTP

Mythbusting

• The Truth: Grounding on one or both side has

no effect on radiation of a STP system

One side

Mythbusting EN 55022 / FCC part 15 - Radiation

Two sides

• General radiation of the cabling systems

• The U/UTP systems have the biggest radiation

• One reason for ANEXT issues

EN 55022 / FCC part 15 - RadiationMythbusting

The Fairy Tales

• STP systems act like an antenna and radiate

• STP system need to be grounded on both sides

• STP requires more complex earthing and bonding

• STP systems have ground loops and current on the screen

• STP has a lot of installation disadvantages

(speed/space/screen)

Mythbusting

STP requires

earthing/grounding

on both sides

Grounding on both sides

• The Myth: A shielded system must be grounded on both sides

to achieve a good EMC performance

Mythbusting

Electromagnetic field

Burst impulse

Conducted electromagnetic field

Grounding on both sides

• The Truth: EMC testing according the MICE definitions

did not show any improvement when grounded on both sides

Mythbusting

E1/E2

E3

The Fairy Tales

• STP systems act like an antenna and radiate

• STP system need to be grounded on both sides

• STP requires more complex earthing and bonding

• STP systems have ground loops and current on the screen

• STP has a lot of installation disadvantages

(speed/space/screen)

Mythbusting

Earthing Systems

and

Ground Loops

Earthing

• The Myth: STP System require complex earthing

systems

Mythbusting

Earthing

• The Truth: The standards specify the mandatory use

of the TN-S distribution system.

Independant from UTP or STP !!!

Mythbusting

Grounding is for personal safety

Ground Loops

• The Myth: Current on the Screen due to

improper earthing lead to

malfunction of STP systems

Mythbusting

Ground Loop

• The Truth: 1. TN-S with a good meshed earthing

system does not lead to screen current

2. Furthermore, current on the screen does

not effect data transmission

• Induced current on the

screen according MICE

• No influence on data traffic

while current on the screen

System 03 System 04 System 05

1 GB/s 0,46 A 1,74 A 2,30 A

Mixed 0,48 A 1,90 A 2,40 A

10 GB/s 0,45 A 2,00 A 2,60 A

System 03 System 04 System 05

1 GB/s ���� � �

Mix � � �

10 GB/s � � �

Mythbusting

The Fairy Tales

• STP systems act like an antenna and radiate

• STP system need to be grounded on both sides

• STP requires more complex earthing and bonding

• STP systems have ground loops and current on the screen

• STP has a lot of installation disadvantages

(speed/space/screen)

Mythbusting

Installation

Disadvantages

Installation

• Myths: 1. Slow Installation

2. Much more space required at TO

3. Screen Maintenance required

Mythbusting

• The Truth: STP is quick & easy & small

5

7

9

mm

Installation

Cat. 6A STP cable is smaller thanCat. 6A UTP cable. The smallerthe cable the less spcae is required

UTP STP

Including Screen Contact

Mythbusting

The Fairy Tales

• STP systems act like an antenna and radiate

• STP system need to be grounded on both sides

• STP requires more complex earthing and bonding

• STP systems have ground loops and current on the screen

• STP has a lot of installation disadvantages

(speed/space/screen)

Mythbusting

Conclusion

UTP vs. STP

• This independent 3rd party study clearly shows

– The EMC parameters like ANEXT and coupling attenuation

dominate the cabling channel performance for 10Gb/s

Ethernet Class EA channels

– All arguments against STP come from UTP suppliers and are

not at all based on technical research. There is no

independent 3rd party test from UTP suppliers confirming

their messages

• STP is proven to be better for 10Gb/s and more

Conclusion

Questions ?

Introduction

Performance Mythbusting

Conclusion

UTP vs. STPThe future is shielded