Cisco Systems 71642 manual Common Roaming Issues, Badge Loses Voice Quality while Roaming

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♦If the telephony server is available, initiate a call with a stationary device to the badge.

♦Continually check voice quality while you traverse the total wireless coverage area. If the voice quality is insufficient, perform these tasks:

♦Listen for all unacceptable changes in voice quality and take note of the location and radio values on your laptop and CQ values from the badge.

♦Watch and listen for the badge to roam to the next access point.

♦Note the other available access points in the site survey to check coverage and interference.

∙Make adjustments to access point placement and settings to fine−tune the WLAN, and perform these checks to ensure voice quality:

♦Use the site survey tools and verify that there is no more than one access point per channel with an RSSI value greater than 35 in any given location. Ideally, all other access points on the same channel should have RSSI values as low as possible (preferably less than 20). At the border of the coverage area where the RSSI is 35, the RSSI for all other access points on the same channel should ideally be less than 20.

♦Use the site survey tools to verify that there are at least two access points (total, on separate channels) visible in all location with sufficient signal strength.

♦Check that the access points in a given roaming area are all on a Layer 2 network.

Common Roaming Issues

These roaming issues can occur:

∙The badge does not roam when placed directly under the access point.

∙The badge is most likely not reaching the roaming differential thresholds for the received signal strength indicator (RSSI) and channel utilization (CU). Adjust the Transmit Power Threshold form the WLC.

∙The badge does not receive beacons or probe responses from the access point.

∙The badge roams too slowly.

The Badge Loses Connection to the Network or Voice Service is Lost when Roaming

∙Check authentication for a possible WEP mismatch.

∙The badge does not send out IGMP joins or the network sends IGMP queries during a roam. Therefore, the Vocera broadcast function fails during a Layer 2/Layer 3 roam.

∙The badge is capable of seamless Layer 2 roaming only (unless a Layer 3 mobility mechanism is configured). Ensure that the new WLC is not serving a different IP subnet.

∙Verify that the associated access point/controller has IP connectivity to the Vocera Communication Server.

∙Check the RF signal strength and badge CQ values.

Badge Loses Voice Quality while Roaming

∙Check for low RSSI on the destination access point.

∙Channel overlap might be insufficient. The badge must have time to hand off the call smoothly before it loses its signal with the original access point.

∙The signal from the original access point might be lost.

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Contents Deployment Scenarios Document IDPrerequisites IntroductionExecutive Summary Requirements Components UsedVocera Badge Overview Vocera SolutionVocera Call Capacity Considerations Vocera Communications Server CapacityArchitecture Overview Voceras Infrastructure PlanningUnicast−Multicast Delivery Method Multicast in an Lwapp DeploymentLwapp Multicast−Multicast Multicast−Multicast Delivery MethodEnable IP Multicast Routing Router and Switch Multicast ConfigurationEnable PIM on an Interface Deployment Scenarios Disable Switch Vlan Igmp SnoopingMulticast Enhancements in Version 4.0.206.0 and Later Single Controller Deployment Single Controller in Multicast−Multicast ModeMultiple Controller Layer 3 Deployment Multiple Controller Layer 2 DeploymentConstruction Methods and Materials VoWLAN Deployments Ciscos ReccommendationsInventory Leap Considerations Security Mechanisms SupportedVoice, Data and Vocera VLANs Wireless Network InfrastructureNetwork Sizing Deployments and Configuration Switch RecommendationsBadge Configuration Tune AutoRF for Your Environment ∙ How do I know if the tranmit power is too hot or too cold? Create Interfaces Wireless Network Infrastructure ConfigurationCreate the Vocera Voice Interface Wireless−Specific ConfigurationWlan Configuration Wlan ConfigurationAP Detail Configure Access Point DetailConfigure the 802.11b/g Radio Wireless IP Telephony Verification Association, Authentication, and Registration Badge Loses Voice Quality while Roaming Common Roaming IssuesRegistration and Authentication Problems Audio ProblemsOne−sided Audio Choppy or Robotic AudioAppendix a AP and Antenna PlacementSignal Reflection Caused by a Wall Cisco Aironet 5959 Antenna Mounted to a Ceiling Interference and Multipath Distortion Signal−to−Noise Ratio SNRSignal Attenuation NetPro Discussion Forums − Featured ConversationsRelated Information
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