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Designing and Deploying Wireless IP Communications Systems. Mike Coffin TME IPCBU/VTG. Enterprise Mobility - Market Overview. Enterprise Customer Demand: IPC mobility is becoming enterprise requirement to meet increasing number of mobile workers needs - PowerPoint PPT Presentation
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1© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Designing and Deploying Wireless IP Communications Systems
Mike CoffinTME IPCBU/VTG
2© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Enterprise Mobility - Market Overview
• Enterprise Customer Demand:
IPC mobility is becoming enterprise requirement to meet increasing number of mobile workers needs
IPC mobility is an integrated call control and voice application solution that customers wish to purchase directly from IPT vendor
• Enterprise IPC Mobility solution categories:
1) Single mode solutions (i.e. 7920s for wireless enterprise voice)
2) Single number reachability (i.e. IP PBX extension to cellular application)
3) Dual mode solutions (i.e. two line DM, call hand-off, etc.)
3© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Voice over WLAN How to Justify
Employee Productivity • Reduced call backs, fewer call attempts • Single mailbox, fewer duplicate messages• Flexibility: choice of device and location for calls• End-to-end IP telephony
Customer Satisfaction • Increases speed of response• Flexible communication flow with media choices• Personalized service • Location and Identification services
OPEX Reductions• Predictable/controllable cellular expenses• Least cost routing/Intelligent on corporate network• Better visibility, better control
Device consolidation
4© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Worldwide Wi-Fi Handset Unit Breakdown
94%
48%49%
29%
16%
9%
71%
51%52%
6%
91%
84%
0%
25%
50%
75%
100%
CY04 CY05 CY06 CY07 CY08 CY09
Calendar Year
Reve
nue S
hare
(%)
Wi-Fi VoIP
Dual-modeWi-Fi/cellular
VoWLAN Market Figures
Source: Infonetics 2005
• IPC (wired/wireless) is growing at 19% CAGR
• ~6% of WLANs are currently running VoWLAN (SMB-Ent)increasing to ~20% in 2007
• 36% of IPC customers view mobility as the driving app todayincreasing to 47% by 2007
• Of the VoWLAN deployments, 50% are using a single mode phone
• Singlemode share is expect to decrease to 38% by 2007
• Dualmode share is expect to increase to 37% by 2007
5© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
• Deployment guidance• WLAN/Network
readiness assesment
Deployment Success
• Mobility a driver for convergence
• Costs savings +productivity increase
Extend IPC investmentsthrough mobility
Thought Leadership in key areas• MFP• Location Awareness (LBAC and IDS)• NAC, NIC, Multi-Layer IDS
Re-seize the security high groundThought Leadership in key areas• Advanced QoS/CAC• Wide support for handsets• Enabling technologies – HD/Mesh/e911
Wireless Voice Strategy
Innovation
Unification & InvestmentProtection
Messaging
6© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
A Business Class Wireless Experience
Unified built-in support of leading edge applications - not an after thought. Cisco Wireless Location Appliance, Wi-Fi phones, and Guest Access
Advanced Mobility Services
World Class NMS that visualizes and helps secure your air space. Cisco Wireless Control System (WCS)
World-Class Network Management
Cisco Self-Defending Network
Seamless network infrastructure across a range of platforms. Cisco 4400, 2000 Wireless LAN Controllers. Cisco Catalyst 6500 Series WiSM, ISR and 3750 integration.
Network Unification
Mobility Platform APs dynamically configured and managed through LWAPP. Cisco Aironet Access Points: 1500, 1300, 1240AG, 1230AG, 1130AG, and 1000. Bridges: 1400 and 1300.
Secure clients that work out of the box
Client Devices
What's in Business Class Wireless?
Future
7© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Headquarters – New York
PSTN
Cisco ISR• Security Services (FW, IDS, etc.)• VoIP Gateway• SRST
T1
Branch Office – Newark, NJ
DSLBranch Office – Austin, TX
WAN
Internet
SiSi SiSi
IPC Infrastructure• CallManager• Unity• Conferencing Media Gateways•MeetingPlace
Cisco Integrated Services Router (ISR) Pair• WAN Access• Security Services (FW, IDS, CSA, VSM etc.)• VoIP Gateway• HSRP
Integrated Wired and Wireless Network •WLSM for Fast Secure L3 Roaming •Aironet WLAN Infrastructure with WLSE Mgt/Control
A Comprehensive VoWLAN Solution
Wireless Voice Clients•Cisco 7920 •CCX clients •Partner Clients •Cisco IPC Client
Integrated Wired & Wireless Network •Wireless AP’s •WLSE Express Management
Wireless Voice Clients
Cisco ISR• Security Services (FW, IDS, etc.)• VoIP Gateway• SRSTIntegrated Wired & Wireless Network •Wireless AP’s •WLSE Express Management
Wireless Voice Clients
8© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
• Lightweight solution
Lightweight AP + WLAN controller + Cisco WCS
• Features
High-accuracy location
Downstream WLAN QoS
APIs for software integration
• Benefits
Ease of use and simplified deployment
Protection from unauthorized access and WLAN attacks
Scalability with controller clustering
Reliability N:1 automated failover
Location aware
• Leadership
Dual Band AP deployment with simultaneous support of 802.11a and 802.11g
Estimated 14 simultaneous calls per AP for .a and 7 simultaneous calls per AP .g
Cisco has proven experience deploying VoWLAN in the enterprise
White Papers, Deployment Guides, Presentations, Training, etc.
Leverage Cisco Advanced Services to accelerate voice over WLAN expertise
Cisco WCS
Cisco WLAN Office Controller
Cisco WLAN Remote Office
Controller
Cisco Lightweight
APs
Cisco Lightweight
APs
Unified Wireless Network
9© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
What Does an Enterprise WLAN Needfor Wireless Voice ?
• Good Voice Quality
• Security
• Fast Roaming
• Ubiquitous Coverage
• Scalability
• Long Battery Life
• Troubleshooting Tools
• Managed RF Environment
WirelessAccessPoints
AP1200 AP1130
Cisco-brand &Cisco-CompatibleClients
Controllers & Switches
Controllers Cat 6500 Series
BR1300
Cisco Wired + Wireless Infrastructure Centralized Management
10© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Innovating in VoWLAN with
CCX v2CCX v2
• Client Tx sync
• AP neighbor list
• Fast Roaming/CCKM (LEAP)
CCX v3CCX v3
• WME compliance
• Fast Roaming/CCKM (FAST)
CCX v4CCX v4
• Fast Roaming/CCKM (PEAP/TLS/TTLS)
• QBSS Load IE
• CAC (TSPEC)
• U-APSD
• Traffic stream metrics
• GPR handling
• Roaming element
• Voice metricsCCX v5CCX v5CCX Version 4 is what we
need clients to be at for dense deployments
11© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Benefits of Cisco’s VoWLAN Solution
• Enterprise-class SecurityWPA encryption + 802.1X authentication
• Secure, Low-Latency Roaming between AP’s and SubnetsUsing standards-based security (WPA + 802.1X)
• Improved Battery LifeProxy ARP allows phone to skip broadcast/multicast beacons, so device can wakeup/go-to-sleep more quickly and stay in doze mode for longer periods of timeSubstantial improvement in standby time
Savings depends on the amount of broadcast/multicast traffic on the networkTransmit Power Sync reduces transmit power, resulting in improved talktime
• QoS for prioritization of voice traffic over data trafficSupports converged voice + data WLAN networksFully compatible with installed base of 802.11 clientsWi-Fi Standard WMM-based QoS now available on Cisco AP’s
12© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Why New Site Surveys?
• Increased roaming with VoWLAN
• Coverage must be seamless with adequate overlap for smooth roaming handoffs
• Old site surveys need to be revisited to ensure the WLAN meets the VoWLAN requirements
13© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Typical WLAN Data Topologies
Wireless Clients
LAN Backbone
Channel 1
Access Point
Wireless “Cell”
Access Point
Wireless “Cell”
Channel 6
Wireless Clients
Ove
rlap
pin
g
10-1
5%
14© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Ch 1Ch 6
Ch 11
Ch 6
Ch 6 Ch 11Ch 1
Greater Overlap Needed
Single Floor Site Survey for Voice: 802.11b
15© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
IDEAL VoWLAN RF ENVIRONMENT
Cisco Unified Wireless IP Phone Cells Should Have Overlap of 15-20%
Redundancy throughout cell
Cisco Unified Wireless IP Phone Cells Should Have Overlap of 15-20%
Redundancy throughout cell
Maintain Proper Separation of Cells
(see deployment guide for recommendations)
Maintain Proper Separation of Cells
(see deployment guide for recommendations)
-67dbm at Edge(see deployment guide for
recommendations)
-67dbm at Edge(see deployment guide for
recommendations)
16© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Flr 1
Flr 2
Flr 3
Flr 4
AP 1
Ch 1
AP 2
Ch 11
AP 4
Ch 1
AP 3
Ch 6
Multi-Floor Site Survey
17© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Ideal Environment
• Reduction of noise
Noise leads to static and choppy voice
More APs / clients will increase the noise levels
• Proper RF overlap
Faster / smoother roaming
Provide a secondary AP if one of the APs is unavailable or congested
Load-Balancing
• Correct data rates
Faster data transmissions, reduction of AP utilization, more calls per AP
18© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Ideal Environment
• Minimum 2 access points on non-overlapping channels at all times with:
RSSI >= 35 (minimum value) -67dBm
CU (QBSS) load < Max Threshold
• Provides for redundancy and load-balancing
Definitions:
RSSI (Received Signal Strength Indicator)
CU (Channel Utilization)
QBSS (QoS Basic Service Set)
19© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Ideal RF Environment
• Non-overlapping cells are 22 MHz apart
1, 6, 11 (North America)
1, 6, 11 or 2, 7, 12, etc. (Europe and Japan)
Do not have to be exactly 5 channels apart (i.e. 1, 7, 13)
1 2 6 113 4 5 7 8 9 12 13 1410
2.402 GHz 2.484 GHz
Channels
22 MHz
20© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Non-Overlapping Channels
• Phone will scan all channels at power up
• Attempts to associate to AP with the highest signal
• Will periodically scan all channels after association giving priority to discovered non-overlapping channels
1
6
11
1
6
11
1
6
11
1
21© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
802.11g Radios
• Disable 6, 9, and 12 Mbps for 802.11g
Will reduce throughput if enabled
• Set 802.11g rates as “enable” vs. “required”
• 7920 phones are 802.11b only
• Enable all other 802.11g data rates for data devices
22© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Signal to Noise Ratio (SNR)
• Signal of -67 dBm or higher
• Packet Error Rate (PER) no higher than 1%
• Minimum SNR of 25dB = -92dBm noise level
Time (Seconds)
Noise Level
RSSI / Signal Strength
Power (dBm)
Adding signal does not always increase SNR
Signal to Noise Ratio
23© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Recommended SNR Values
Data Rate(Mbps)
Data Cell WIPT Cell
MinimumSignal
Strength(dBm)
MinimumSNR(dB)
MinimumSignal
Strength(dBm)
Minimum SNR(dB)
54 -71 25 -56 40
36 -73 18 -58 33
24 -77 12 -62 27
11 or 12 -82 10 -67 25
5.5 or 6 -89 8 -74 23
2 -91 6 -76 21
1 -94 4 -79 19
24© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
COMPARISON OF 802.11 SPECTRUM– Throughput & Channels
Data Rate (Mbps)
Approximate Throughput
(Mbps)
Non-Overlapping
Channels
802.11b 11 6 3
802.11g (with .11b clients in cell)
54 8 3
802.11g (no .11b clients in cell)
54 22 3
802.11a 54 25 19
25© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Dynamic Transmit Power Control (DTPC)
• Set the same transmit power on the AP and on the phones
If using an AP that supports DTPC, then ensure client power matches the local AP power
(Do not use default setting of Max power)
If the AP does not support DTPC, then need to statically set the phone’s transmit power to match the AP with the highest transmit power in the WLAN (default 7920 setting = 20mW)
• Prevents one-way audio
i.e. RF traffic is only being heard in one direction
100mW 20mW
26© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Multi-Path
• AP antennas need placements that are away from reflective surfaces
• Maximize line of sight
NEVER MOUNT ANTENNAS NEAR METAL OBJECTS or REFLECTIVE SURFACES
P1
P2
P3
TX RX
Ceiling
Obstruction
Floor
27© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Diversity
• Match the antenna types and ensure they cover the same radio pattern
• If using cable extenders, should be the same length and type
28© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Note: These numbers can vary depending on the specific RF environment and the amount of data traffic
Ideal Environment
• G.711 - 7 concurrent voice streams
• G.729 - 8 concurrent voice streams
(# of 7920s on call per AP)
• Call numbers are with Voice Activity Detection (VAD) disabled, which is recommended
• Voice quality maintained with standard data traffic on AP
29© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Set Expectations
• Difficult to achieve 99.999% availability with VoWLAN (2.4 Ghz)
• The better the RF environment is controlled the better the quality will be
• Coverage in elevators is challenging
• Recommended to use CCKM when doing 802.1x authentication otherwise voice gaps may exist during roaming
30© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Site Survey Process
Site Survey
• Identify areas in the physical environment where there is non 802.11 RF interference
• Identify and eliminate rogue APs
• Identify key utilization requirements
• Determine proper AP location and transmit power levels
• Proper configuration of APs
• Proper configuration on network and server
31© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
• Assists you in the assessment
Type of survey needed
How long it will take
Equipment needed
Introduction to the customer’s facility
• General fact gathering form
Pre-Site Survey Form
32© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Site Survey
• Survey each floor individually then combined to check leakage
• Ensure testing is done with users and wireless network traffic
• Do not assume all channels can be used in every environment
• Try to logically segment subnets based on roaming behavior
• Keep in mind users will talk in locations where they don’t normally use wireless data
Staircases
Quiet locations
33© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Off-hours or Green Site Survey
• No noise during site survey, however will be post deployment
• Measure noise during the day or at other similar deployments
Equivalent number of people and devices
Similar type of RF utilization
34© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Evaluate Key Areas
Break Room (Microwave Ovens - 2450 Mhz)
File / Supply Room
(Large Filing or Metal Cabinets)
Stairwells (Reinforced
Building Area)
Elevator Shafts Test Lab
ConferenceRoom
Office
Cubes VIP (CEO)
35© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Site Maps
Coverage Not Required
Low Capacity Areas
High Capacity Area
Stock Room—Metal ShelvesP
arki
ng
Gar
age
Office
Cubes
36© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Site Survey Report
• Be very specific when describing locations
• Use tape and facility markers
• A picture is worth 1,000 words
• Antenna orientation
Not all installers familiar with the equipment
The more directional an antenna is, the more important the orientation description has to be
37© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Incorrect Placement of APs
• Incorrect placement of APs can lead to coverage or quality issues
Move AP a minimum of 2 feet from metal beam
38© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Incorrect Placement of APs
• Mount a wood board between metal tracks
39© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Incorrect Antenna Orientation
• Antennas are pointing incorrectly
• Point the antennas toward the desired coverage area
40© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Long-Term Site Survey Report
• Site survey report is required for the life of the WLAN deployment
Configurations of the APs
Location of the APs
Channel and transmit power map
Switch port configurations
AP model types
Coverage map per frequency
Antenna type per AP
41© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Tools for VoWLAN Site Surveys
• WLSE assisted site survey tool is currently NOT recommended for voice deployments
(The minimum cell overlap for seamless roaming is not present)
• WLSE is recommended for managing APs post-deployment
• Use tools like Airmagnet Analyzer and Surveyor, Cognio Spectrum Anaylzer
• Finish using end-user devices such as Cisco Unified Wireless IP Phone 7920 and wireless laptops to ensure 100% coverage and quality
42© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Installation and Network Verification
• As important as site survey
• Insures entire system works as designed
• Make actual phone calls to test voice quality
• Phone equipment requirements:
Headsets to monitor RSSI and communicate on Cisco Unified Wireless IP Phone 7920
Call between Cisco Unified Wireless IP Phone 7920 and wired Cisco Unified IP phone
• Wired infrastructure pre-requisite:
Proper wired network must be in place
www.cisco.com/go/srnd
43© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Installation Verification
• Suggested test areas:Primary area of each AP cell (1)
Any location where there might be high call volume (2)
At the fringes of an AP’s coverage area (3)
Areas of where overlap might be questionable (4)
At locations where coverage might be slightly questionable but still need to be certified (i.e. stairwells, bathrooms, etc.)
1
23
4
Conference Room
44© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Wireless Voice Verification Plan (WVV)
• Important every time changes are made to:
Wired network
Wireless network
Physical environment
End user devices
(Voice or data)
45© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID
Q and A
46© 2005 Cisco Systems, Inc. All rights reserved.Session NumberPresentation_ID