ZEBRA TC51 Voice Deployment Optimization with Aruba User Guide

: June 4, 2024
: ZEBRA

Table of Contents

About This Guide
Device Settings
Device Wi-Fi Quality of Service (QoS) Tagging and Mapping
Network Settings and Device RF Characteristics
Infrastructure and Vendor Model Recommendations
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TC51, TC56, TC70x,
TC75x, MC33
Best Practices Guide
Voice Deployment
Optimization with Aruba
Infrastructure
MN-003538-03EN Rev A

Copyright

ZEBRA and the stylized Zebra head are trademarks of Zebra Technologies Corporation, registered in many jurisdictions worldwide. All other trademarks are the property of their respective owners. ©2021 Zebra Technologies Corporation and/or its affiliates. All rights reserved. Information in this document is subject to change without notice. The software described in this document is furnished under a license agreement or nondisclosure agreement. The software may be used or copied only in accordance with the terms of those agreements.
For further information regarding legal and proprietary statements, please go to:
SOFTWARE: zebra.com/linkoslegal.
COPYRIGHTS: zebra.com/copyright.
WARRANTY: zebra.com/warranty.
END USER LICENSE AGREEMENT: zebra.com/eula.
Terms of Use
Proprietary Statement
This manual contains proprietary information of Zebra Technologies Corporation and its subsidiaries (“Zebra Technologies”). It is intended solely for the information and use of parties operating and maintaining the equipment described herein. Such proprietary information may not be used, reproduced,
or disclosed to any other parties for any other purpose without the express, written permission of Zebra Technologies.
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Continuous improvement of products is a policy of Zebra Technologies. All specifications and designs are subject to change without notice.
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About This Guide

This guide is jointly authored by Zebra Technologies and Aruba Networks.
This guide provides recommendations for voice deployment using the following mobile computers and their accessories.

TC51
TC51-HC
TC56
TC70x
TC75x
MC33.

Notational Conventions
The following conventions are used in this document:

Bold text is used to highlight the following:
Dialog box, window, and screen names
Drop-down list and list box names
Checkbox and radio button names
Icons on a screen
Key names on a keypad
Button names on a screen
Bullets (•) indicate:
Action items
List of alternatives
Lists of required steps that are not necessarily sequential.
Sequential lists (for example, those that describe step-by-step procedures) appear as numbered lists.

Icon Conventions
The documentation set is designed to give the reader more visual clues. The following graphic icons are used throughout the documentation set. These icons and their associated meanings are described below.
NOTE: The text here indicates information that is supplemental for the user to know and that is not required to complete a task. The text here indicates information that is important for the user to know.
Related Documents
For the latest version of this guide and all documentation sets for the respective devices, go to: zebra.com/support.
Refer to Aruba’s RF and Roaming Optimization documentation for more details about Aruba’s infrastructure.

Device Settings

This chapter includes device settings for default, supported, and voice traffic recommendations.
Default, Supported, and Recommended for Voice Device Settings
This section includes specific recommendations for a voice that are not set as the default out-of-the-box configuration. It is generally advised to examine those specific settings in alignment with the WLAN network needs and compatibilities. In some cases, changing the defaults could harm generic onnectivity
performance.
Besides those specific recommendations which would need careful examination, most of the device’s default settings are already optimized for voice onnectivity. For that reason, it is recommended to keep the defaults and let the device dynamically adjust the WLAN network dynamic feature-selection levels.
Device configuration should change only if there are WLAN network (wireless LAN controller (WLC), access points (AP)) features that mandate respective changes on the device side to allow proper inter-operation.
Note the following:

Pairwise master key identifier (PMKID) is disabled on the device by default. If your infrastructure configuration is configured for PMKID, enable PMKID and disable the opportunistic key caching (OKC) configuration.
The Subnet Roam feature allows you to change the network IP of the WLAN interface when the network is configured for a different subnet on the same extended service set identification (ESSID).
In execution of default fast transition (FT) (also known as FT Over-the-Air), in case that other non-FT Fast Roaming Methods might be available on the same SSID, see Fast Roam Methods in Table 5 and relevant notes in General WLAN Recommendations on page 14.
Use mobile device management (MDM) agents to change settings. Use the user interface (UI) to change parameter subsets.
For voice applications, and for any highly-dependent client-server communication apps, it is not recommended to use the Android battery optimization feature (also known as Doze Mode) in device management tools. Battery optimization interrupts communication between dependent endpoints and servers.

The following table lists the default, supported, and recommended voice settings.
Table 1 Default, Supported, and Recommended Voice Device Settings

Feature| Default Configuration| Supported Configuration|

Recommended for Voice

---|---|---|---
State11d| Country selection set to Auto| •Country selection set to Auto
•Country selection set to Manual| Default
ChannelMask_2.4 GHz| All channels are enabled, subject to local regulatory rules.| Any individual channel can be enabled or disabled, subject to local regulatory rules.| Device Mask matches the exact set of network side operating channels configuration.
It is recommended to configure both the device and the network to a reduced set of channels 1, 6, and 11, if WLAN SSID is enabled on 2.4 GHz.

Table 1 Default, Supported, and Recommended Voice Device Settings (Continued)

Feature| Default Configuration| Supported Configuration| Recommended for Voice
---|---|---|---
ChannelMask_5.0 GHz| All non-dynamic frequency selection (DFS) channels are enabled, subject to local regulatory rules.| Any individual channel can be enabled or disabled, subject to local regulatory rules.| Device Mask shall match the exact set of network side operating channels configuration.
It is further recommended to configure both the device and the network to a reduced set of only non-DFS channels. For example, in North America, configure the network channels to 36, 40, 44, 48, 149, 153, 157, 161, 165.
Band Selection| Auto (both 2.4 GHz and 5 GHz bands enabled)| •Auto (both bands enabled)
•2.4 GHz
•5 GHz| 5 GHz
Band Preference| Disabled| •Enable for 5 GHz
•Enable for 2.4 GHz
•Disable| Enable for 5 GHz, if WLAN SSID is on both bands.
Wi-Fi Sleep Policy| Never| •Always On
•Never On| Default
Open Network Notification| Disabled| •Enable
•Disable| Default
Advanced Logging| Disabled| •Enable
•Disable| Default
User Type| Non-Restricted| •Enable
•Disable| Default
FT| Enabled| •Enable
•Disable| Default
FT Over The DS| Enabled| •Enable
•Disable| Default

Table 1 Default, Supported, and Recommended Voice Device Settings (Continued)

Feature| Default Configuration| Supported Configuration|

Recommended for Voice

---|---|---|---
OKC| Enabled| •Enable
•Disable| Default
PMKID| Disabled| •Enable
•Disable| Default
Power Save (PS)

Note: The default PS of the device side does not require PS config change on the network side.

Device Wi-Fi Quality of Service (QoS) Tagging and Mapping

This section describes device QoS tagging and mapping of packets from the device to the AP (such as outgoing packets in the uplink direction).
The tagging and mapping of traffic in the downlink direction from the AP to the device is determined by the AP or controller vendor implementation or configuration, which is not in the scope of this document.
For the uplink direction, an application on the device sets Differentiated Service Code Point (DSCP) or Type of Service (ToS) values for its sourced packets, based on the application’s specifications. Prior to the transmission of each packet over Wi-Fi, the DSCP or ToS values determine the device’s further 802.11 Tagging ID assigned to the packet and the mapping of the packet to the 802.11 Access Category.
The 802.11 tagging and mapping columns are provided for reference and are not configurable. The IP DSCP or ToS values may or may not be configurable, depending on the app.
NOTE:Table 2 describes the tagging and mapping values for outgoing packets when no other dynamic protocols affect them by standard specifications. For example, if the WLAN infrastructure mandates the Call Admission Control (CAC) protocol for certain traffic types (such as voice and/or signaling), tagging and mapping obey the dynamic states of the CAC specifications. This means that there could be CAC configurations or sub- periods in which the
tagging and mapping apply different values than mentioned in the table, even though the DSCP value is the same.
Table 2 Device Wi-Fi QoS Tagging and Mapping for Outgoing Traffic

IP DSCP
Class Name| IP DSCP
Value| ToS Hexa| Tagging of 802.11 TID (Traffic ID) and UP (802.1d UserPriority)| Mapping to 802.11
Access Category (same as Wi-Fi WMM AC
spec)
---|---|---|---|---
none| 0| 0| 0| AC_BE
cs1| 8| 20| 1| AC_BK
af11| 10| 28| 1| AC_BK
af12| 12| 30| 1| AC_BK
af13| 14| 38| 1| AC_BK
cs2| 16| 40| 2| AC_BK
af21| 18| 48| 2| AC_BK
af22| 20| 50| 2| AC_BK
af23| 22| 58| 2| AC_BK
cs3| 24| 60| 4| AC_VI
af31| 26| 68| 4| AC_VI
af32| 28| 70| 3| AC_BE
af33| 30| 78| 3| AC_BE
cs4| 32| 80| 4| AC_VI
af41| 34| 88| 5| AC_VI
af42| 36| 90| 4| AC_VI
af43| 38| 98| 4| AC_VI

Table 2 Device Wi-Fi QoS Tagging and Mapping for Outgoing Traffic (Continued)

IP DSCP
Class Name| IP DSCP
Value| ToS Hexa| Tagging of 802.11 TID (Traffic ID) and
UP (802.1d UserPriority)| Mapping to 802.11 Access Category (same as Wi-Fi WMM AC spec)
---|---|---|---|---
cs5| 40| A0| 5| AC_VI
ef| 46| B8| 6| AC_VO
cs6| 48| C0| 6| AC_VO
cs7| 56| E0| 6| AC_VO

Network Settings and Device RF Characteristics

This section describes device settings for the recommended environment and device RF characteristics.
Recommended Environment

Perform a Voice Grade Site Survey to ensure the requirements in Table 3 are met.
Signal Noise Ratio (SNR), measured in dB, is the delta between the noise in dBm and the coverage RSSI in dBm. The minimum SNR value is shown in Table 3. Ideally, the raw noise floor should be -90 dBm or lower.
At floor level, Same-Channel Separation refers to two or more APs with the same channel in RF sight of a scanning device in a given location. Table 3 specifies the minimum received signal strength indicator (RSSI) delta between these APs.

Table 3 Network Recommendations

Setting|

Value

---|---
Latency| < 100 msec end-to-end
Jitter| Country selection set to Auto
Packet Loss| < 1%
Minimum AP Coverage| -65 dBm
Minimum SNR| 25 dB
Minimum Same-Channel Separation| 19 dB
Radio Channel Utilization| < 50%
Coverage Overlap| 20% in critical environments

Table 3 Network Recommendations

Setting|

Value

---|---
Channel Plan| 2.4 GHz: 1, 6, 11
•No adjacent channels (overlapping)
•Overlapping APs must be on different channels 5 GHz: 36, 40, 44, 48, 149, 153, 157, 161, 165
•If you are using DFS channels, broadcast the SSID in beacons.
•Note: Unlicensed National Information Infrastructure-2 (U-NII-2) (DFS channels 52 to 140) and U-NII-3 (channels 149 to 165) are subject to the local regulatory rules

Device RF Capabilities
Table 4 lists the RF capabilities supported by the Zebra device. These are not configurable.
Table 4 RF Capabilities

Setting|

Value

---|---
Roam Threshold| -65dbm (cannot be modified)
Device-specific Antenna Configuration| •TC51: 2×2 MIMO

•TC51-HC: 2×2 MIMO

•TC56: 1×1 SISO

•TC70x: 2×2 MIMO

•TC75x: 2×2 MIMO

•MC33: 2×2 MIMO

11n Capabilities| A-MPDU Tx/Rx, A-MSDU Rx, STBC, SGI 20/40 etc.
11ac Capabilities| Rx MCS 8-9 (256-QAM) and Rx A-MPDU of A-MSDU

Infrastructure and Vendor Model Recommendations

This section includes recommendations for Aruba infrastructure settings, including WLAN practices for enabling voice as well as more specific recommendations to manage voice traffic and maintain expected voice quality.
This section does not include a full list of Aruba configurations, but only those required verification to accomplish successful interoperability between Zebra devices and the Aruba WLAN network.
The listed items may or may not be default settings of the given Aruba controller version. Verification is advised.
See Related Documents on page 5 for more detailed information on recommended network settings.
General WLAN Recommendations
This section lists recommendations to optimize WLAN to support voice deployment.

For best results, use Wi-Fi Certified (voice enterprise certification from Wi-Fi Alliance) AP models.
If SSID for voice is enabled on 2.4G band, do not enable the 11b-legacy data rates on that band unless specifically required by some restricted coverage planning or older legacy devices must be supported.
The device chooses to roam or connect to an AP depending on the infrastructure settings in effect and the underlying dynamics of the RF ecosystem. Generally, the device scans for other available APs at certain trigger points (for example, if the connected AP is weaker than -65 dBm) and connects to a stronger AP if available.
802.11r: Zebra strongly recommends that the WLAN network supports 11r FT as a fast-roaming method to achieve the best WLAN and device performance and user experience.
11r is recommended above other fast-roaming methods.
When the 11r is enabled on the network, either with pre-shared-key (PSK) security (such as FTPSK) or with an authentication server (such as FT-802.1x), the Zebra device automatically facilitates 11r, even if other parallel non-11r methods co-exist on the same SSID network. No configuration is needed.
Disable unused Fast Roam Methods from the SSID if possible. However, if older devices on the same SSID support a different method and two or more methods may remain enabled if they can coexist. The device automatically prioritizes its selection per the Fast Roaming Method in Table 5.
It is a general best practice to limit the amount of SSID per AP to only those required. There is no specific recommendation on the number of SSIDs per AP as this depends on multiple RF environmental factors that are specific to each deployment. A high number of SSIDs impacts channel utilization
which comprises not only users and application traffic but also beacon traffic of all SSIDs on the channel, even those not in use.
Call Admission Control (CAC):
The network’s CAC feature is designed to facilitate VoIP deployments but uses algorithmic complexities to determine whether to accept or reject new calls based on network resources in runtime.
Do not enable (set to mandatory) CAC on the controller without testing and validating the stability of admissions (calls) in the environment under stress and plurality conditions.
Be aware of devices that do not support CAC which are using the same SSID as Zebra devices that support CAC. This scenario requires testing to determine how the network CAC impacts the entire ecosystem.

WLAN Infrastructure Recommendations for Voice Support
Table 5 WLAN Infrastructure Recommendations for Voice Support

Setting|

Value

---|---
Infra type| Controller-based
Security| WPA2
Voice WLAN| 5 GHz only
Encryption| AES
Authentication: Server-Based (Radius)| 802.1X EAP-TLS/PEAP-MSCHAPv2
Authentication: Pre-Shared Key (PSK) Based, if necessary.| Enable both PSK and FT-PSK.
Note: Device automatically selects FT-PSK. PSK is necessary to support legacy /non-11r devices on the same SSID.
Operational Data Rates| 2.4 GHz:
•G: 12, 18, 24, 36, 48, 54 (disable all lower rates, including 11b- legacy)
•N: MCS 0 -15 5 GHz:
•A:12, 18, 24, 36, 48, 54 (disable all lower rates)
•AN: MCS 0 – 15
•AC: MCS 0 – 7, 8
Note: Adjust rate settings according to environmental characteristics. See Recommended Environment on page 12 to accomplish balanced AP minimum coverage.
Fast Roam Methods (See General WLANRecommendations on page14)| If supported by infrastructure:
•FT (802.11R)
•OKC or PMK Cache
Note: Device priority order from the top.
Beacon Interval| 100

Table 5 WLAN Infrastructure Recommendations for Voice Support (Continued)

Setting|

Value

---|---
Channel Width| 2.4 GHz: 20 MHz 5 GHz: 20 MHz
WMM| Enable
802.11k| Enable only Neighbor Report. Do not enable any 11k measurements.
802.11w| Disable
802.11v| Enable
AMPDU| Enable
Note: Local environmental/RF situations (such as high interference levels, collisions, and obstructions) may yield a local high retries ratio, delays, and packet drops. The AMPDU feature can degrade voice performance in addition to the challenging RF. In such cases, it is recommended to disable the AMPDU.

Aruba Infrastructure Recommendations for Voice Quality
This section lists specific Aruba infrastructure recommendations to manage voice traffic and maintain expected voice quality.
NOTE: If the deployment has services that require service discovery, set broadcast filtering to ARP only. Consult with Aruba if there are address- resolution issues with the respective discovery protocol.
Table 6 Aruba Infrastructure Recommendations for Voice Quality

Recommendation| Required|

Recommended But Not Required

---|---|---
Set delivery traffic indication message (DTIM) interval to 1. Note: A value of 2 is also acceptable for certain deployments depending on the voice application (and other voice-related aspects such as Push-to-Talk), as well as on the potentially mixed types of devices sharing the same SSID, the battery life of each type, and the Power Save configuration of each client product.| ✓|
Create a dedicated user role on Aruba for voice devices, according to application deployment needs. Create a session access control list (ACL) and place the voice protocols in the prioritized high queue.| ✓|
Broadcast Filtering set to All or address resolution protocol (ARP).| ✓|
Disable Dot1x Termination.| ✓|
Set Probe Retry to its default Enable.| | ✓
Set Max Tx Failure to its default Disable (max-tx-fail=0).| ✓|
Enable 802.11d/h.| ✓|

Table 6 Aruba Infrastructure Recommendations for Voice Quality (Continued)

Recommendation| Required|

Recommended But Not Required

---|---|---
Enable Mcast-rate-opt (needed for multicast to go at the highest rate).| | ✓
The beacon rate is set with a rate that is also basic rate.| | ✓
Set Local Probe Request Threshold to its default of 0 (disabled).| ✓|
Disable Band Steering.| ✓|
Enable voice Aware Scan and ensure voice traffic of the given ACL definition (of the deployed App) is detected on the controller.| ✓|
Disable 80 MHz support.| | ✓

Additional Configurations for Voice Multicast Applications
Zebra PTT Express Deployment
The following lists recommendations of additional Aruba infrastructure settings to support PTT Express:

dynamic-multicast-optimization
Converts Multicast to Unicast with a higher data rate
demo-channel-utilization-threshold 90
Falls back to Multicast traffic from Unicast if the channel utilization reaches 90%
Zebra Recommended WLC and AP Models
NOTE: Model versioning recommendations in this section are based on satisfactory interop
test plan results. Zebra recommends that when using other software versions not listed below,
consult the WLC/AP in the Release Notes to verify that a particular version is stable and preferred
by the vendor.
Aruba Controllers 73xx, 72xx, and 70xx:
Software versions: 8.7.1.x, 8.8.0.1
Campus-AP Models: 303H, 303 Series, 30x, 31x, 32x, 33x, 34x, and 51x
IAP 300 series, 31x, 32x, 33x, 34x, and 51x:
Software versions: 6.5.4.8, 8.7.1.x, 8.8.0.1
IAP 200 series:
Software version: 6.5.4.6