Table of Contents. This guide describes the configuration of ADTRAN NetVanta 150 AP with the NEC MH240 Mobile Handsets. NEC Unified Solutions, Inc.

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1 Page 1 of 6 VOICE INTEROPERABILITY TEST RESULTS FOR NEC UNIVERGE MH240 MOBILE HANDSET AND ADTRAN NETVANTA 150 ACCESS POINTS Table of Contents Product Summary 2 MH240 Mobile Handset Design with 3 rd Party Access Points 3 Network Configuration 3 WLAN Coverage 3 Data Rate 3 Impact of WLAN retransmissions 3 Dynamic Channel Assignment 3 Voice Call Admission Control 3 Handover times 3 Battery Life Considerations 4 DTIM Timer 4 Impact of Multicast Traffic 4 AP Configuration 5 Configuration Options and features 5 Test Results- Summary This guide describes the configuration of ADTRAN NetVanta 150 AP with the NEC MH240 Mobile Handsets.

2 Page 2 of 6 Product Summary Manufacturer ADTRAN Model Name NetVanta 150 Software Revision 1.00.B AP Radio(s): 2.4 GHz (802.11b/g) Security: WEP, WPA-PSK, WPA2-PSK, Handset model tested MH240 Handset software tested: (NA) Radio mode: 2.4 GHz (802.11b/g) Network Topology One subnet Known Service Conditions and/or Limitations Service Conditions/Limitations that may affect battery life: 1. ADTRAN NetVanta 150 AP does not support adjusting DTIM timer. NEC recommends DTIM timer to be a value of 5, AP is set at 1. Decrease in battery standby time could encountered 2. ADTRAN NetVanta 150 AP does not support filtering of broadcast/multi-cast traffic per SSID. In situations where AP is shared with multiple SSID and no filtering on voice SSID; result would result decrease in battery standby time. Service Conditions/Limitations that may affect voice quality: 1. ADTRAN NetVanta 150 AP does not allow 1 and 2 Mbs to be disabled. In incorrect network configurations and extending MH240 out of range, the result can be frame error rates to any or all MH240 handsets connected to that AP 2. ADTRAN NetVanta 150 AP does not support CAC, a method to limit the maximum number of clients (MH240 handsets) per radio. 3. ADTRAN NetVanta 150 AP does not support fast handover, as defined by f. Handover time between AP ranged from ~ ms during our test. A brief quiet may be experienced during handover This application note describes the configuration of ADTRAN NetVanta 150 access points with the NEC MH240 Mobile Handsets.

3 Page 3 of 6 MH240 Mobile Handset Design with 3 rd Party Access Points When designing and implementing the NEC MH240 handset on 3 rd party Wireless LAN Controller configuration and/or autonomous access point s specific configuration settings may or may not be supported and thus may have impact on battery life and/or voice quality. There are certain key wireless configuration considerations that directly affect the overall NEC MH240 VoWLAN design and implementations NETWORK CONFIGURATION WLAN COVERAGE RF design is critical. The MH240 handset design and implementation best practices require that each AP support approximately 2500 square feet. As always distances that AP can support are influenced of specific building construction and local environment NEC recommends that the RSSI value between access points be no more than -55Dbm. It is also recommended that the access point be set to half power (50 mw) to better align with the transmit power of the MH240 and thus reduce the near/far affect DATA RATES The goal in setting the data rates for the VoWLAN network is to match the data rates of MH240 handsets as closely as possible Mbps and 2Mbps should not be supported. Any lowering of the data-rate below 5.5Mbps, extends the AP cell size, increases co-channel interference, and reduces call capacity. The best practices for data rates for the MH240 handset are to enable all data rates except 1 and 2 Mbps. Both 1 and 2 Mbps must be disabled to dramatically reduce retransmissions: IMPACT OF WLAN RETRANSMISSIONS Voice is a real time application and unlike other data traffic, too many retransmissions can deteriorate voice quality. NEC recommends the Tx Retry settings be set to no more than 5 DYNAMIC CHANNEL ASSIGNMENT Radio Resource Management (RRM) can adjust AP channels (dynamic channel assignment) and power (dynamic transmit power control) to maintain the RF coverage and quality. The radio configuration of each AP, both Auto-RF and dynamic channel assignment, must be disabled VOICE CALL ADMISSION CONTROL VoWLAN Voice Call Admission Control (CAC) prevents rejection of calls when suitable capacity is available. A standards based solution is not available and as a result all 3 rd party access points will not support this feature and high simultaneous calls must be considered carefully HANDOVER TIMES When working with any 3 rd party access point vendor, fast handover, as defined by the f is not supported. Therefore, depending on the particular 3 rd party AP vendor handover times between AP ranged from ~ ms. During that time a brief quiet may be experienced.

4 Page 4 of 6 BATTERY LIFE CONSIDERATIONS DTIM TIMER Some VoWLAN handsets might require the delivery traffic indication Map (DTIM) to be increased to maximize battery life, but this change should only be done based on design recommendation specific to the handset. The DTIM period sets the number of beacon intervals that a WLAN client will sleep before waking up to see whether any traffic has been buffered for it (when in power save mode). IMPACT OF MULTICAST TRAFFIC Multicast and broadcast traffic must be buffered as well as any unicast traffic when destined for power saving clients. This can affect application performance, so DTIM should only be adjusted to the levels recommend by NEC. DTIM settings are usually global for the band and are not changed on a per WLAN basis; therefore, changing the DTIM value will affect each WLAN on a given AP radio. Given that the multicast traffic on a WLAN is sent out to every AP radio with clients associated to that WLAN regardless of that client(s) requirements, every effort should be made to minimize the multicast traffic on every WLAN interface. You can minimize the potential effects of multicast traffic by disabling IGMP on interfaces not requiring multicast and filtering multicast traffic on interfaces that have IGMP enabled. Some access point vendors use Proxy ARP, or the address resolution protocol This process is called Proxy ARP because on network system (wireless controller) is providing the proxy for the MH240 handsets. This provides controller based APs another method to filter unwanted multicast/unicast messages to the MH240 handsets When this is an option for the AP vendor, NEC highly recommends this solution for saving batteries life on the MH240 handsets

5 Page 5 of 6 AP Configuration Configuration Options and features The following is a list of AP configuration options or features that have a potential impact on the operation or performance of the MH240 Mobile Handsets. Recommended or required value noted below should be used. Please record the value or setting that was used in your testing. AP Option/Feature DHCP IP Static IP Recommended Configuration Settings Recommend DHCP Results from testing Supported b/g Recommended: g Supported SSID Recommended: Setup a separate voice SSID for MH240 only Supported Security Recommended: WPA2-PSK Supported QoS settings / WMM VoWLAN Call Admission Control Packet Filter and Proxy ARP Recommended: Platinum COS Specify if there is any supported Supported Not-Supported Not-Supported Broadcast ESSID Recommended: Enable or Disable Supported Dynamic Radio Channel Control Power-Save mode Required: Disable Set to 5 Not applicable Not-Supported Tx Retry settings Recommended: 5 retries Supported Tx power level Recommend half power (50mw) Supported Beacon interval Required: 100ms Supported DTIM Required: 5 Not-Supported

6 Page 6 of 6 AP Configuration, Continued Configuration Options and features AP Option/Feature Data rates Recommended Configuration Settings 54 - Enabled 48- Enabled 36- Enabled 24 - Supported 18 - Supported 11 - Supported 9- Enabled 6- Enabled 5.5- Enabled 2 - Disabled 1 - Disabled Required: 1Mbps and 2Mbps must be disabled. Results from testing 54 - Supported 48- Supported 36- Supported 24 - Supported 18 - Supported 11 - Supported 9- Supported 6- Supported 5.5- Supported 2 Not Supported 1 Not Supported Not Supported