Transcript WiFi VoIP: From Installation to Implementation

WiFi VoIP: From Installation to
Implementation
David Fridley
Product Manager IP Telephony Solutions
Telecommunication Systems Division
Phone: 949-583-3692
[email protected]
Agenda
 What is WiFi?
 Deploying Voice over WiFi
 Cases/Examples
What is WiFi?
 WiFi is like a meeting…
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When the moderator speaks, everyone listens.
If you want to speak, listen and wait for the current
speaker to finish before speaking.
Don’t interrupt someone who is speaking.
If you were not heard, wait and try again.
WiFi Telephony
 VoIP is an application that runs on IP networks.
 Voice over WiFi is a natural step in this evolution…
 First: Soft Phones on PCs
 Second: WiFi on Laptops
 Then: WiFi Telephony was born
Comparison with Other Technologies
Ability to be connected to the phone system
even if users are not at their desks
Compared to Cellular:
Compared to Cordless:
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Manage coverage area
Data access as well as voice
Interoperable with many devices
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Manage coverage area
Data access as well as voice
Cost of WiFi is part of the
network infrastructure expense,
distributed over the enterprise.
Cellular is a variable expense.
Enterprise - Specific Features
 Ability to tie into your IP-based phone system and
provide all desktop phone features to a WiFi device
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Hold
Transfer
Call Announce
“Line 1”
 Guests
 Remote/mobile employees
Network Topology / User Mobility
Cellular
PR
W
IC
00 A
W
00 A
E
TT
H
W AC
T/C
H
C
TIC
H
/C
C
O
K A
O
L
CT/C
H
1A
CT/C
H
1 C
L2
Switc
h
PSTN
Branch
Office
NB
PDA
CIX Server IPT
Local status bar
►5 Flexible ►0 Flexible
►4 Flexible ►9 Flexible
►3 Flexible ►8 Flexible
►2 Flexible ►7 Flexible
►1 PDN
►6 Flexible
2x24 Row 2 display
2x24 Row 1 display
N
B
P
D
A
Hot Spot
Internet
VoIP Anywhere
Line Unit
(T1, DSL,,,,)
L2 Switch
Broadband
Modem
BB Router
PBX
Server
Office
IPT
NB
Local status bar
►5 Flexible ►0 Flexible
►4 Flexible ►9 Flexible
►3 Flexible ►8 Flexible
►2 Flexible ►7 Flexible
►1 PDN
►6 Flexible
2x24 Row 2 display
2x24 Row 1 display
PDA
Local status bar
►5 Flexible ►0 Flexible
►4 Flexible ►9 Flexible
►3 Flexible ►8 Flexible
►2 Flexible ►7 Flexible
►1 PDN
►6 Flexible
2x24 Row 2 display
2x24 Row 1 display
NB
IPT
SoHo
Special Needs of WiFi Telephony
 Voice wants all the packets to get through right
away.
 Voice needs a fixed amount of bandwidth.
If that is not possible, voice is not possible.
Deploying Voice Over WiFi
 Good enough for data is not good enough for Voice
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Special needs of Voice
Wireless network assessment
Coverage and other concerns
Testing the network
Security
WiFi
WiFi Standard
802.11b
802.11g
802.11a
Data Rate
11Mbps
54Mbps
54Mbps
Separate Channels
3
3
8
Distance at full rate
197 feet
66 feet
82 feet
Band
2.4GHz
2.4GHz
5GHz
End-point devices
IP Phones, PDAs,
Laptops
Laptops
Laptops
Bigger or Faster
24 Users / 11Mbps =
24 Users / 22Mbps =
460 Kbps per user
920 Kbps per user
Max ~7 VoIP calls
Max ~14 VoIP calls
Voice Over WiFi: Expectations
 About 7 – 10 active calls per access point
 Difficult to prevent too many calls
 Need to prioritize voice traffic over data traffic
over-the-air WiFi WMM™
Quick Test for a WiFi Network
 A voice-ready WiFi network should have at least
99% packets getting through
 Quick Test
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Start ->run->"cmd"
"ping -n 60 -l 160 -w 250 <IP Address>"
Security
 Prevent unauthorized access to the
enterprise network over the WiFi
network
 Prevent unauthorized access into
wireless computers over the
wireless network and the Internet
 Guest Access to the Internet?
 Fast handoff when moving from
one Access Point to the next
IP Sub-netting
 Single Subnet or Multiple Subnets?
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How many users/wireless users
• < 200 Single
• > 1000 Multiple
 When crossing from an AP in one
subnet to another, the voice session
will disconnect because the device
IP address changes.
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Mobile IP
Wireless Switch
The Future of WiFi Telephony
 Dual Mode WiFi/Cell Phones
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Carrier dialing plan on the WiFi network
Enterprise dialing plan on the Cellular network
 Quality of Service
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SIP based access control
802.11e based access control (this year!)
Keys to Successful
WiFi Telephony Implementation
 Plan in advance for coverage
 Types of endpoints
 How many access points and where
 Bandwidth requirements
 Consider QoS for Voice
 WMM minimum
 Plan for access control
 Security that does not impact Voice
 Consider the mobility needs of employees
 Assess the wireless network
Cases
 Dentist Office uses WiFi to link two neighboring offices together,
installing IP phones in the remote office
 Furniture Store uses WiFi and IP desk phones to enable quick and easy
reconfiguration of show rooms
 Travel Agency lets people work from home, and provides 24 hour
support
 Florist has IP desk phones, but employees need to be able to move
around and still be part of the call group
 Manufacturing facility has a steel building, so cordless phones won’t
work well…access points on low power installed to provide better
coverage (still being evaluated)
Example: Wireless Network Assessment
 50,000 sq-ft facility
 ~120 users
 802.11b access points
Example: Wireless Network Assessment
Example: Wireless Network Assessment
Audience
Q&A