Transcript Site Survey and Installation

Module 10
Site Survey and Installation
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-1
Overview
This module will cover the actual WLAN site survey and
installation. Topics covered in this module include the
importance of infrastructure awareness, and creating an
accurate network map as an initial step in conducting a
site survey. Mounting and installation concerns will also
be covered. Although determining the appropriate
coverage area involves trial and error, experience and
proper network maps can greatly assist the survey
engineer. Finally, the student will learn how to document
the entire process by creating a site survey report or by
appropriately responding to Request for Proposals
(RFPs).
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-2
Learning Objectives
•Identify potential difficulties that may arise while
designing a wireless LAN due to the current
configuration of the wired LAN.
•Make suggestions on how to make changes to the
wired LAN configuration to accommodate a wireless
LAN.
•Make suggestion on how to reconfigure wired LAN
infrastructure equipment to support a wireless LAN.
•Identify potential design problems associated with
network cabling.
•Identify facts and potential problems with mounting
antennas and access points.
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-3
Learning Objectives
•Identify facts on splitter and connectors.
•Recommend the proper equipment for
plenum spaces.
•Identify what should be included in a site
survey document.
•Define characteristics of RF propagation.
•Identify proper placements of access points.
•Identify access points limitations.
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-4
Key terms
• Fire Wall
• Riser
• Service Loop
• NEMA
• RFP
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-5
LAN Infrastructure Awareness
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-6
LAN Infrastructure
IT personnel already
overworked and not
looking to increase
workload
Customer expects a
professional, detailed,
all inclusive site survey
A good site survey and
report will lead to future
business for your
company
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-7
LAN Infrastructure (cont.)
Get to know the customer’s network
Know topologies
Have an IT representative walk you through
the facility and show you the network
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-8
LAN Infrastructure - Media
Know the types and
the limitations
Copper vs. Fiber
Access points
provide copper
connections only
Transceivers
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-9
Operating Systems, Protocols, and
Drivers
Operating Systems
used on Clients
Protocol need for
the wireless LAN
Not all O/S have
supporting drivers
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-10
Switches
Ability for each port
to be seen as a
“virtual” LAN
Not “just fancy hubs”
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-11
Switches (cont.)
Designed for
stationary users
VLAN 1
Switch
VLAN 2
See mobile devices
as wandering from
VLAN to VLAN
Accommodate Cisco
Aironet Access
Points
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-12
Switches (cont.)
VLAN 1
VLAN 3
Switch
VLAN 2
STOP
Host
Data
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-13
Switches (cont.)
Group devices
on a single
VLANs
Switch
Host
Data
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-14
Switches (cont.)
Switch
VLAN
Data
© 2003, Cisco Systems, Inc. All rights reserved.
Host
FWL 1.0—10-15
Switches (cont.)
Use VLANs to
propagate across
access points
VLAN 101
VLAN 102
Access points
handle up to 16
VLANs
VLAN 102
Use a router to
span across
VLANs
VLAN 100
© 2003, Cisco Systems, Inc. All rights reserved.
VLAN 101
FWL 1.0—10-16
Routers
Present considerations
similar to switches
• Stop broadcast packets
• Must be configured for IP Helper
Address in order to pass DHCP
packets
May indicate
• Remote host
• May require static route
• Need for support of Proxy Mobile
IP
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-17
Other Considerations
VLAN 1
DHCP addresses for
mobile users on
VLANs
Application “least
common
denominator”
Host
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-18
Proxy Mobile IP
Home Agent / Foreign Agent
Home Agent / Foreign Agent
AP 2.2.2.157
AP 1.1.1.30
Laptop 1.1.1.39
Before Roam
Laptop 1.1.1.39
After Roam
Client is in the subnet of AP.
Client IP address does not change.
All traffic directly connecting to client.
Since AP is in a different subnet all
traffic must go through router for
directions.
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-19
Site Survey
Make customer
aware of potential
problems
Be proactive instead
of reactive
Your chance to help
the customer
Reputations win
further business
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-20
Site Survey
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-21
RF Propagation
Radio waves are
reflected just
like light waves
Can reduce the
reflected waves
by using
directional
antennas
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-22
RF Propagation (cont.)
Waves 1800 out of
phase will create a
“null” or dead spot
Use diversity
antennas to help
overcome nulls
When using a single
antenna, change the
antenna location to
overcome the null
© 2003, Cisco Systems, Inc. All rights reserved.
Nulls
FWL 1.0—10-23
RF Propagation (cont.)
If the RF wave is
unable to pass
through an object, it
may suffer from
Diffraction
Diffraction creates
RF “shadows”
© 2003, Cisco Systems, Inc. All rights reserved.
Shadow
FWL 1.0—10-24
Preparation
Prior to arrival
• Ensure your equipment is
operational
• Configure equipment (if
possible)
• Determine if manlift is
needed
• Who will provide the lift?
• Make sure batteries are
fully charged
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-25
Site Survey
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-26
Site Survey (cont.)
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-27
Channel Selection
AP 5
AP1
Channel 1
AP 3
Channel 6
Channel 11
AP 4
AP 2
Channel 6
© 2003, Cisco Systems, Inc. All rights reserved.
Channel 1
AP 6
Channel 11
FWL 1.0—10-28
Data Rates
Surveyed at 2 Mbps
© 2003, Cisco Systems, Inc. All rights reserved.
Surveyed at 5.5 Mbps
FWL 1.0—10-29
Antenna Choice, Power Level, & Cell
Size
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-30
Site Survey Problems
Process of trial and
error
Experience = more trial,
less error
Talk with other
engineers
Site surveys can be
puzzles
More than one solution
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-31
Site Survey Problems (cont.)
Frustration and laziness are
your enemies
Take a break
May be necessary to start
survey over
Always design the WLAN
properly
Do not try and “force” your
original plan to work
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-32
Site Survey
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-33
Freezers
o
Perishable Goods 36 F
Freezer 0o F
© 2003, Cisco Systems, Inc. All rights reserved.
Freezer -5o F
Freezer -20o F
FWL 1.0—10-34
Antenna Splitters
WRONG!
Freezer
OK
OK
2.4 GHz Technology
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-35
Multi-floor Survey
AP 4
AP 3
AP 2
AP 1
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-36
Site Survey
Trauma Room
No coverage
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-37
Interference
Coverage cell seems small in comparison with
previously surveyed access points
Coverage from access point seems to be
intermittent
Mount antennas in open areas for best RF
propagation
Look for objects that may interfere with RF signal
May need to use Spectrum Analyzer to find
interference
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-38
Interference (cont.)
Cardboard
Electrical
Transformers
© 2003, Cisco Systems, Inc. All rights reserved.
Wood
Microwave
Ovens
Paper
Firewalls
Fluorescent
Lighting
FWL 1.0—10-39
Mounting and Installation
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-40
WLAN Design Considerations
Access points have to be
connected to the network
Should be familiar with:
• Network components
• Media
• Topology
Need to have some
knowledge
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-41
Plenum
A compartment or
chamber to which one
or more air ducts are
connected
Forms part of the air
distribution system
Cat 5 cable available in
plenum and non-plenum
Non-plenum sheath is
PVC and gives off toxic
fumes when melted
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-42
Plenum (cont.)
Cat 5 available
• Plenum
• Non-Plenum
Plenum areas
• Egg crate ceiling tiles
• No insulation
• Firewalls
Non-plenum areas use
ducting in plenum for
air return
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-43
Plenum (cont.)
No chance for toxic
fumes to get inside
the ducting
Non-plenum areas
• Ductwork
• Lack of firewalls
• Insulation
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-44
Firewalls
Easily identified
Act as barriers to
contain fires
Hinders 2.4 GHz
signal
Stops 5 GHz signal
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-45
Firewalls (cont.)
Some firewalls may
have doors
Fire doors can hamper
the RF signal as well
Survey with doors
closed
Automatic Fire Doors
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-46
Risers
Sometimes referred to
as “wiring closets”
Used for wiring between
floors
Stacked on top of each
other
Riser walls are firewalls
If a riser is plenum-rated,
only install plenum rated
equipment
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-47
1200 Series Access Point Mounting
Mounting holes
Mounting
solutions
•
•
•
•
Concrete
Drywall
I-Beam
Ceiling
Secure the access
points
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-48
Mounting on a Horizontal or Vertical
Surface
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-49
Mounting on a Suspended Ceiling
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-50
Attaching and Securing the Access
Point to the Mounting Bracket
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-51
1100 Series AP:
Variety of Mounting Configurations
Desktop
Stand
Wall
Mount
© 2003, Cisco Systems, Inc. All rights reserved.
Ceiling
Mount
Hang on
Cube Wall
FWL 1.0—10-52
Access Point Mounting (cont.)
Do not cover
access point lights
Mount “upside-down”
so Ethernet indicator
lights can be seen from
the floor
Label access points
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-53
Antenna Mounting
Some antennas
not shipped with
mounting brackets
Mast
Mount
Patch
Modify brackets
• Fit your needs
• Can be used with a
variety of antennas
Ceiling
Mount
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-54
Antenna Mounting (cont.)
Solid and secure
Do not hang antennas
by their cable
• Cable can break or
become damaged
• Antenna can sway and
provide a “moving cell”
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-55
Antenna Mounting (cont.)
Sometimes antennas
are mounted in
unusual ways
Specify in your report
exactly how the
antenna is to be
mounted
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-56
NEMA Enclosures
Protect equipment in
harsh environments
NEMA - National
Electronics
Manufacturers
Association
Rating system NEMA 1 - 13
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-57
NEMA Enclosures (cont.)
NEMA type 2, 4, 4x
most commonly used
for WLAN equipment
Can be purchased
through local
hardware distributors
Do not come
equipped for WLAN
equipment
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-58
NEMA Enclosures (cont.)
Mounting plate
with standoffs
Electrical
Workbox
Bulkhead Extender
External Antenna
Connector
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-59
NEMA Enclosures (cont.)
Pre-fabricated NEMA enclosures are
available with all of the necessary
connections
Special NEMA enclosures are available with
solar panels or temperature control
Make sure NEMA enclosures are mounted
securely to avoid injury or damaged
equipment
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-60
Antenna Extension Cables
Antenna and access
point location
Cisco offers
• LMR 400 style cables
– 20 and 50 ft.
– Total loss of 1.3 and 3.4
dB respectively
• LMR 600 style cables
– 100 and 150 ft.
– Total loss of 4.4 and 6.6
dB respectively
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-61
Antenna Extension Cables (cont.)
Consider loss for cables and connectors
Use Cat 5 cable to locate access point as
close to antenna as possible
Can buy custom length cables from third
party companies
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-62
RP-TNC Connectors
RP-TNC connectors
available from Cisco
RG-58 should not be
used for extension
cables
N-style extension
cables
• Jumpers
• As much as 3.5 dBi loss
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-63
Splitters
Understand losses attributable
to splitters
Most use N-style connectors
RP-TNC splitters are available
Splitter attaches to access
point and antennas using
extension cable jumpers
Jumpers are LMR 400 cables
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-64
Splitters (cont.)
Each antenna
connected to the
splitter suffers 4 dBi
loss
Doubles
• Number of antennas
• Not the coverage area
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-65
Documentation
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-66
Site Survey Report
Is the deliverable
Customer needs
detailed information
All information
gathered during the
site survey should be
included in the report
© 2003, Cisco Systems, Inc. All rights reserved.
Site
Survey
Report
FWL 1.0—10-67
Site Survey Report (cont.)
Be as specific as possible
You are the surveyor; you may not be the
installer
Report is protection for you and your
customer
Date your report
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-68
Site Survey Report (cont.)
Be very specific when describing locations
Use objects and facility markers
Do not use object or markers that may be
temporary
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-69
Site Survey Report (cont.)
Antenna orientation
• Not all installers familiar with the equipment
• The more directional an antenna, the more
important the orientation description
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-70
Site Survey Report (cont.)
Describe the facility
Discuss tools used and survey methods
Mention settings used for survey
Describe and diagram access point
coverage
Mark areas that are covered as well as those
not needing coverage
Have customer sign and return a copy of
the report
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-71
Site Survey Report (cont.)
Proper access point, antenna, and power
mounting
Proposed cabling runs
System components
Future expansion
Site survey objective
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-72
Site Survey Report (cont.)
Parts List
• Access points
• Antennas
• Accessories and network components
Diagrams
Photographs
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-73
Site Survey Report (cont.)
List contacts
• Name
• Company
• Address
• Phone & Fax
• E-mail
List contacts for all companies involved
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-74
Summary
• Identify potential difficulties that may arise while designing a
wireless LAN due to the current configuration of the wired LAN.
• Make suggestions on how to make changes to the wired LAN
configuration to accommodate a wireless LAN.
• Make suggestion on how to reconfigure wired LAN
infrastructure equipment to support a wireless LAN.
• Identify potential design problems associated with network
cabling.
• Identify facts and potential problems with mounting antennas
and access points.
• Identify facts on splitter and connectors.
• Recommend the proper equipment for plenum spaces.
• Identify what should be included in a site survey document.
• Identify proper placements of access points.
© 2003, Cisco Systems, Inc. All rights reserved.
FWL 1.0—10-75
© 2003, Cisco Systems, Inc. All rights reserved.
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