Lab 2.6.1 Mnemonics for Cabling
Estimated Time: 30 minutes
Number of Team Members: Up to six
Objectives:
•
Use of mnemonics as a learning aid.
•
Use mnemonics to remember the seven layers of the OSI reference
model.
•
Develop mnemonic devices for things that are not conceptual, such as
sequences of colors.
Overview:
A mnemonic is a memory trick that makes it easier to retain information. For
instance, the five names of the Great Lakes in the United States (Huron, Ontario,
Michigan, Erie, and Superior) can be remembered by taking the first letters of
each to create the mnemonic “HOMES”.
In this lab, students will use mnemonics to help remember the layers of the OSI
model and the color-coding schemes of wires.
Tools and Resources:
•
A pencil or pen
Step 1 The OSI Model
The seven layers of the OSI model are the following:
1 - Physical
2 - Data Link
3 - Network
4 - Transport
5 - Session
6 - Presentation
7 - Application
One mnemonic that is popular among those in the networking industry is: “All
People Seem To Need Data Processing”. Notice that the first letter of each word
in the phrase is also the first letter of the names of the OSI layers starting with
the 7th layer, the Application Layer.
Another popular mnemonic for the OSI model starts with the 1st layer, the
Physical Layer: “Please Do Not Throw Sausage Pizza Away”.
Copyright  2003, Cisco Systems, Inc.
Fundamentals of Voice and Data Cabling 1.2 - Lab 2.6.1
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Now create an original mnemonic for the OSI model. Make one starting with the
1st layer and one starting with the 7th layer of the OSI model. Try to think of
mnemonics that are easy to remember.
Physical
_________________
Application
_________________
Data Link
_________________
Presentation
_________________
Network
_________________
Session
_________________
Transport
_________________
Transport
_________________
Session
_________________
Network
_________________
Presentation
_________________
Data Link
_________________
Application
_________________
Physical
_________________
Step 2 Four-Pair Cable
A mnemonic can also be used to help memorize other things. This picture is one
such example:
1.The
Sky is
Blue
2.The
Sun is
Orange
3.The
Tree is
Green
4.The
Earth is
Brown
The Blue – Orange – Green – Brown pattern is the order of the pairs inside a
four-pair wire.
Make a mnemonic to describe this sequence of colors:
White
Red
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Fundamentals of Voice and Data Cabling 1.2 - Lab 2.6.1
Copyright  2003, Cisco Systems, Inc.
Black
Yellow
Violet
Step 3 Multi-Pair Cable
1.The
Sky is
Blue
2.The
Sun is
Orange
4.The
Rocks
are Gray
or Slate
3.The
Tree is
Green
4.The
Earth is
Brown
The Blue – Orange – Green – Brown pattern is the same as the order of the
pairs inside a four-pair wire.
Blue – Orange – Green – Brown – Slate
White – Red – Black – Yellow – Violet
The two color cycles listed above are the colors used to differentiate the pairs
used in nearly all voice cable, even 1800-pair cable. The first 25 pairs come
together in the following sequence.
Copyright  2003, Cisco Systems, Inc.
Fundamentals of Voice and Data Cabling 1.2 - Lab 2.6.1
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The first group of wire pairs can be identified by the Tip color:
Pair 1 is White /Blue
Pair 2 is White /Orange
Pair 3 is White /Green
Pair 4 is White /Brown
Pair 5 is White /Slate
Starting with Pair 6, the Tip color changes to Red and the Ring colors repeat
themselves.
Pair 6 is Red /Blue
Pair 7 is Red /Orange
Starting with Pair 11, the Tip color changes to Black and the Ring colors repeat
themselves. This color pattern is continued for all 25 pairs in the cable.
Be aware that some cable manufacturers will stripe the wires in the first 25 pairs.
Each wire in a pair will be striped with the color of the other wire in that pair. For
example, the white wire in pair 1 would have a blue stripe, and the blue wire in
that pair would have a white stripe. The higher multiples will be described later.
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Fundamentals of Voice and Data Cabling 1.2 - Lab 2.6.1
Copyright  2003, Cisco Systems, Inc.
Copyright  2003, Cisco Systems, Inc.
Fundamentals of Voice and Data Cabling 1.2 - Lab 2.6.1
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