AudioCodes C435HD User manual

User's and Administrator's Manual
AudioCodes 400HD IP Phone Series
C435HD IP Phones
Microsoft Teams Application
Version 1.12
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Notice C435HD Users & Administrator's Manual
Notice
Information contained in this document is believed to be accurate and reliable at the time
of printing. However, due to ongoing product improvements and revisions, AudioCodes
cannot guarantee accuracy of printed material after the Date Published nor can it accept
responsibility for errors or omissions. Updates to this document can be downloaded from
https://www.audiocodes.com/library/technical-documents.
This document is subject to change without notice.
Date Published: July-13-2021
WEEE EU Directive
PursuanttotheWEEEEUDirective,electronicandelectricalwastemustnotbedisposedof
withunsortedwaste.Pleasecontactyourlocalrecyclingauthorityfordisposalofthisproduct.
Customer Support
Customertechnicalsupport and services areprovided by AudioCodes orby an authorized 
AudioCodes  Service  Partner.  For  more  information  on  how  to  buy  technical  support  for 
AudioCodes  products  and  for  contact  information,  please  visit  our  website  at 
https://www.audiocodes.com/services-support/maintenance-and-support.
Documentation Feedback
AudioCodes  continually  strives  to  produce  high  quality  documentation.  If  you  have  any 
comments(suggestionsorerrors)regardingthisdocument,pleasefillouttheDocumentation
Feedbackformonourwebsiteathttps://online.audiocodes.com/documentation-feedback.
Stay in the Loop with AudioCodes
Related Documentation
Document Name
https://docs.microsoft.com/en-us/MicrosoftTeams/phones-for-teams
C435HDIPPhoneforMicrosoftTeamsQuickGuide
C435HDIPPhoneforMicrosoftTeamsReleaseNotes

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Content C435HD Users & Administrator's Manual
Table of Contents
1 Overview 1
Specifications 1
Allowing URLs, Ports (Security) 3
Security Guidelines for Android-based Native Teams Devices 4
Android-Level Security Hardening 5
Google Play Services 5
Running Android in Kiosk Mode 6
Screen Lock 6
AudioCodes Private Key 6
Android Debug Bridge (ADB) 6
App Signing 6
Web Browser 6
Remote Configuration Management 7
AudioCodes Device Manager Validation 7
Sandboxing 7
Device File System 7
Keystore 7
Device Certificate 8
Data Protection 8
Debugging Interface 8
Android Security Updates 8
AudioCodes Root CA Certificate 8
2 Setting up the Phone 11
Unpacking 11
Device Description 12
Front View 12
Rear View 15
Cabling 16
Mounting the Phone 16
Before Using AudioCodes Devices 16
3 Starting up 17
Configuring Device Settings 17
Restoring the Phone to Default Settings 29
Performing a Hard Restore 29
Performing a Soft Restore 30
Recovery Mode 31
Locking and Unlocking the Phone 31
Automatic Lock 31
Unlock 31
4 Teams Application 33
Signing In 33
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Content C435HD Users & Administrator's Manual
Multi-Cloud Sign-in 37
Remote Provisioning and Sign-in from Teams Admin Center 38
Getting Acquainted with the Phone Screen 42
Setting Status 43
Configuring Teams Application Settings 44
Using the People Screen 47
Accessing Voicemail 48
Using Audio Devices 49
Transferring Calls and Meetings across Devices 49
Signing Out 49
5 Performing Teams Call Operations 51
Making a Call 51
Dialing a Missed Call 53
Select to Dial 53
Making an Emergency Call 53
Answering Calls 54
Ending an Established Call 54
Managing Calls 54
Transferring a Call to Frequent Contacts 54
Transferring a Call to Work Voicemail 55
Viewing and Playing Voicemail Messages 55
Rejecting an Incoming Call, Sending it Directly to Voicemail 55
Adjusting Volume 55
Adjusting Ring Volume 56
Adjusting Tones Volume 56
Adjusting Handset Volume 56
Adjusting Speaker Volume 56
Adjusting Headset Volume 57
6 Performing Administrator-Related Operations 58
Updating Phone Firmware Manually 58
Downloading 802.1x Certificates 60
AudioCodes Teams IP Phone Utility 60
Manually Performing Recovery Operations 61
Removing Devices from Intune Management 62
Updating Microsoft Teams Devices Remotely 69
Managing Phones with the Device Manager 70
Configuring a Periodic Provisioning Cycle 71
Configuring TimeZone and Daylight Savings 71
Managing Devices with HTTPS 72
Supported Parameters 72
7 Troubleshooting 75
Users 75
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Content C435HD Users & Administrator's Manual
Network Administrators 75
Teams IP Phone Utility 75
Capturing the Phone Screen 77
Running Tcpdump 79
Getting Information about Phones 80
Remote Logging (Syslog) 82
Getting Diagnostics 83
Getting a Bug Report 86
Activating DSP Recording 87
Deactivating DSP Recording 88
SSH 89
Getting the Phone IP Address 89
Installing the Teams APK (or Any Other APK) using SSH 89
Microsoft Admin Center 90
Collecting Logs 90
Getting Company Portal Logs 92
Getting Logs via the Phone 92
Getting Logs using UUID 93
Getting Audio Debug Recording Logs 95
Collecting Media Logs (*.blog) from the Phone 96
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CHAPTER1 Overview C435HD Users & Administrator's Manual
1 Overview
The AudioCodes  C435HD IPphones  areMicrosoft Teams-native entry  level/common  area 
phonesdesignedtosupportthenextgenerationofenterprisecollaborationtechnologieswith
alargecolorLCDscreenandfullUCintegrationfortheNativeMicrosoftTeamsOnlinemarket.
ThephonescanbemanagedbytheMicrosoftTeams&SkypeforBusinessAdminCenter.For
moreinformation,seehere.
Featurehighlights:
■NativesupportforMicrosoftTeams
■Colorscreen4.3":Graphic,480x272resolution,withmulti-lingualsupport
■Multi-lingualsupport
■Fullduplexspeakerphoneandheadsetconnectivity
■DualGbEsupport
■USBheadsetsupport
■PoEorexternalpowersupply
■Calendarandclick-to-joinsupport(Roadmap)
Specifications
ThefollowingtablesummarizesthesoftwarespecificationsoftheAudioCodesIPphonesfor
MicrosoftTeams.
Table 1-1: Software Specifications
Feature Details
Media
Processing
■VoiceCoders:G.711,G.729,G.722,SILKOpus
■AcousticEchoCancelation:G.168-2004compliant,64-msectail
length
■AdaptiveJitterBuffer
■VoiceActivityDetection
■ComfortNoiseGeneration
■PacketLostConcealment
■RTP/RTCPPacketization(RFC3550,RFC3551),SRTP(RFC3711)
Microsoft
Teamsphones
featureset
■Authentication(Signinwithusercredentials;Signinusing
PC/Smartphone;ModernAuthentication;Phonelock/unlock)
■Calling(Incoming/OutgoingP2Pcalls;In-callcontrolsviaUI(Mute,
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CHAPTER1 Overview C435HD Users & Administrator's Manual
Feature Details
hold/resume,transfer,endcall);PSTNcalls;VisualVoicemail;911
support
■CalendarandPresence(roadmapfeature)(CalendarAccessand
MeetingDetails;PresenceIntegration;ExchangeCalendar
Integration;ContactPictureIntegration;CorporateDirectory
Access)
■Meetings(roadmapfeature)(One-clickJoinforMeetings;Join
SkypeforBusinessmeetings;MeetingCallcontrols[Mute/unmute,
hold/resume,hangup,add/removeparticipant];MeetingDetails.
Seealsohere.
Configuration
and
Management
■MicrosoftTeams&SkypeforBusinessAdminCenter(Provisioning
andLogging)
■AudioCodesDeviceManagementandAudioCodesRedirectServer
formonitoring,upgradingandconfiguring
Debugging
Tools
■AudioCodes'TeamsIPPhoneUtility(seeTeamsIPPhoneUtilityon
page75)
■LoguploadtoMicrosoftserver(certificationfor3rdpartySkypefor
Businessclients)
■RemoteloggingviaSyslog
■SSHAccess
■Capturingthephonescreen
■TCPdump
■CompanyPortal(Intune)logs
■AudioDebugrecordinglogs
■Medialogs(*.blog)
■Portmirroringnetworkmonitoring(C450HD)
■RemotePacketCapturenetworksnifferapplication
Localization
Support
■Multi-lingualsupport;thelanguagepacklistisnotyetfinalandis
subjecttomodification.
Hardware ■Graphic4.3"colorscreen,480x272resolution,withmulti-lingual
support
■Wiredconnectivity:
✔TwoRJ-45[GigabitEthernet(GbE)](10/100/1000BaseT
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CHAPTER1 Overview C435HD Users & Administrator's Manual
Feature Details
Ethernet)ports:LANandPCport
✔RJ-9port(jack)forheadset
✔1xUSBportforheadsetsupport
✔RJ-11interface
■Power:
✔DCjackadapter12V
✔PowersupplyAC100~240V
✔PoEClass3:IEEE802.3af(optional)
■Keys:
✔VOICEMAILmessagehotkey(includingLED)
✔4-waynavigationbuttonwithOKkey
✔MENU
✔HOLD
✔MUTE(includingLED)
✔TRANSFER
✔VOLUMEcontrolkey
✔HEADSET(includingLED)
✔SPEAKER(includingLED)
✔BACK
✔CONTACTS
✔Teamshomekey
Allowing URLs, Ports (Security)
ThissectionguidesnetworkadministratorswhichURLs/PortstoallowwhendeployingTeams
phones(security).
Fromthedevicepointofview,thefollowingtablesummariestheportsthephoneuses.See
alsoMicrosoft'sguidetotheportsthephoneuses.
Table 1-2: URLs / Ports to Allow when Deploying Teams Phones (Security)
Server Role Service Name Port Protocol Notes
DNSServer All 53 DNS -
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CHAPTER1 Overview C435HD Users & Administrator's Manual
Server Role Service Name Port Protocol Notes
AudioCodes
Device
Manager
AudioCodes
DM
443 HTTPS AudioCodesdevice
managementserver
AudioCodes
Redirect
service
AudioCodes
DM
443 HTTPS AudioCodesredirectservice
redirect.audiocodes.com
NTP
timeserver
AndroidNTP 123 UDP -
TimeZone
Database
TimeZones 443 HTTPS TimeZoneDatabase(often
calledtzorzoneinfo)
Microsoft
AppsArtifacts
server
Package
manager
- - Microsoftwillberequested
fortheprotocolandportand
FQDN.TheseURLsare
providedbytheAdmin
agent.
Security Guidelines for Android-based Native Teams Devices
AudioCodes'Android-basedNativeTeamsdevicesarepurpose-builtandcustomizedfor
MicrosoftTeamscallingandmeeting.CustomersmightperceiveAndroid-basedproductsas
vulnerabletosecurityissuesbutsecurityislessofanissueondevicespurpose-builtandcus-
tomizedforMicrosoftTeamscallingandmeeting.Securityisinfactenhancedonthesedevices
as part of their default use.
Whenanalyzingdevicesecurity,twolevelsmustbeaddressed:
■AuthenticationandsecuritywithrespecttoTeamsconnectivityanduse
■Androidlevel/systemofthedevice
AudioCodesrecommendsthefollowing:
■Usethesign-inmodeSign-in with other device option.Inthismode,usersdonottype
thepasswordonthedevicebutinsteadobtainacodeontheirPC/laptoptobeusedto
sign-in;thephoneobtainsaprivatetokenthatenablesittoaccessTeamscloud;this
token,unlikeapassword,allowsonlythatdevicewhichobtainedittoreuseit.Thetoken
isstoredonthesecuredfilesystem.
■LeverageMulti-Factor-authentication(MFA)toimprovesign-insecurity.
■Reducetheexpirationtimeofthesign-infordeviceswhichareconnectedremotely
(outsidetheorganization'snetwork)versusdevicesinsidetheorganization'spremises.
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CHAPTER1 Overview C435HD Users & Administrator's Manual
AudioCodesrecommendsvisitingMicrosoft'stechnicalpagesformoresecurityguidelinesand
policiesforMicrosoftTeamsadoption:
■Overviewofsecurityandcompliance-MicrosoftTeams|MicrosoftDocs
■IdentitymodelsandauthenticationforMicrosoftTeams-MicrosoftTeams|Microsoft
Docs
■SignintoMicrosoftTeams-MicrosoftTeams|MicrosoftDocs
Android-Level Security Hardening
MajorAndroid-levelsystem-leveldevelopments have been incorporated into AudioCodes'
NativeTeamsdevicestoimprovesecurity:
■SeeGooglePlayServicesbelow
■SeeRunningAndroidinKioskModeonthenextpage
■SeeScreenLockonthenextpage
■SeeAudioCodesPrivateKeyonthenextpage
■SeeAndroidDebugBridge(ADB)onthenextpage
■SeeAppSigningonthenextpage
■SeeWebBrowseronthenextpage
■SeeRemoteConfigurationManagementonpage7
■SeeAudioCodesDeviceManagerValidationonpage7
■SeeSandboxingonpage7
■SeeDeviceFileSystemonpage7
■SeeKeystoreonpage7
■SeeDeviceCertificateonpage8
■SeeDataProtectiononpage8
■SeeDebuggingInterfaceonpage8
■SeeAndroidSecurityUpdatesonpage8
Google Play Services
GogglePlayserviceswereremovedfromtheAudioCodesNativeTeamsdevicesoftware.Access
toanyGooglestoreorPlayserviceisnotallowed.
■UpdatingtheAudioCodesNativeTeamsdevice'sAndroidsoftwareandapplicationis
performedviaspecialsoftwarecomponentsthateitherconnecttotheTeamsAdmin
CenterortoAudioCodes'DeviceManageroverasecuredchannel.
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CHAPTER1 Overview C435HD Users & Administrator's Manual
Running Android in Kiosk Mode
AndroidKioskLockdownsoftware'locksdown'Androiddevicestoonlyallowessentialappsby
disablingaccesstotheHome/ Launcher.UsingAndroidKiosk Lockdownsoftware,Android
devicescanbeconvertedintopublickioskterminalsorsecuredworkdevices.
■OnlyspecificMicrosoftappsandAudioCodes-signedappsthatwerecertifiedand
approvedinthecertificationprocesscanruninKioskmode;evenifamalicioususer
managestoinstallanewunauthorizedapponthefilesystem,thelauncheronthe
AudioCodesNativeTeamsdevicewillonlyrunthosespecificapprovedappsandthis
cannotbechangedinruntime(onlywithanewsoftwarecodeprovidedbyAudioCodes).
Screen Lock
AudioCodes Native Teams  devices use a  screen lock  mechanism  to  prevent  any  malicious 
user/users  from  gaining  access  to  Calendar  information  and  /  or  Active  Directory  list  of 
employeesand/ortriggeringunauthorizedTeamscallsfromthedevice.Afterenablingscreen
lock,thedeviceautomaticallylocksafterapreconfiguredperiod;acodeisrequiredtounlock
thedeviceandresumefulloperation.
AudioCodes Private Key
ThesystemsoftwareonAudioCodesNativeTeamsdevicesissignedwithAudioCodes'private
key.Userscanreplacethecompletesoftwareonlywithnewsoftwarethatisalsosignedby 
AudioCodes'privatekey.
Thispreventsusersfromreplacingthecompleteover-the-air(OTA)packageofthedevicewith
anynewsystemsoftware,unlessthesoftwareisfullysignedbyAudioCodes.
Android Debug Bridge (ADB)
AudioCodesdisabledtheAndroidDebugBridge(ADB)applicationandkeepstheTeamsapp
runninginthefrontallthetime.Asaresult,it'simpossibletoinstallotherappsfromunknown
sources,andtosideloadapps.
App Signing
Android  requires  all  apps  to  be  digitally- signed  with  a  developer  key  before  installation; 
currently,theAudioCodesNativeTeamsdevicesverifythatappsaresignedbyMicrosoft.
Appsigningpreventsmalicioususer/usersfromreplacingaMicrosoft-signedappwithanapp
that  "pretends"  to  be  Microsoft  but  which  lacks  the  private  key  that  is  known  only  to 
Microsoft.
Web Browser
TheAudioCodesNativeTeamsdevicedoesnotincludeaWebbrowser.Userscannotbrowse
tothepublicinternetorinternalintranet.AllWebservicesarecustomizedtoconnecttoOffice
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CHAPTER1 Overview C435HD Users & Administrator's Manual
365services and AudioCodes'managed services such  as the One VoiceOperations  Center
(OVOC).
WithoutaWebbrowser,malicioususer/userswillnotbeabletoaccessthedeviceandbrowse
fromitasatrusteddeviceintothecustomernetwork.
Remote Configuration Management
AudioCodesNativeTeamsdevicesdonothaveanembeddedWebserver.Configurationand
managementareperformedusingoneofthefollowingremoteinterfaces:
■MicrosoftTeamsAdminCenter(forNativeTeamsdevices)overHTTPSprotocols,enabled
afterasuccessfulsign-inauthenticationprocess.
■AudioCodesDeviceManager(partofAudioCodes'OVOCsuite)overHTTPS.
■DebugginginterfaceoverSSH.NotethatSSHmustbedisabledbydefaultandenabled
onlyperspecificcasefordebuggingpurposesonly.
AudioCodes Device Manager Validation
TheAudioCodesNativeTeamsdevicesvalidatetheAudioCodesDeviceManageridentityusing
aknownRootCA:
■ThedeviceisshippedwithknownRootCAsinstalled.SeeAudioCodesRootCACertificate
onthenextpage.
■Fortheinitialconnection,theAudioCodesDeviceManageraccessesdevicesusinga
knownCA.
■Onceasuccessfulsecuredconnectionhasbeenestablishedbetweenthedeviceandthe
DeviceManager,theusercanreplacetheRootCAontheDeviceManagerandonthe
phone,andre-establishtheconnectionleveraginganyPrivateRootCA.
Sandboxing
AudioCodesNativeTeamsdevicesuseAndroidApplicationSandboxsothateachapplication
canaccessitsowndataandisisolatedfromotherapplications.Thispreventsamaliciousapp
fromaccessingthecodeorthedataofotherapplicationsinthesystem.
Device File System
TheAudioCodesNativeTeamsdevice'sfilesystemisencryptedontheC470HD,C435HDand
C450HD-DBWdevices.Customersmayenforceapolicyofdeviceencryption viaMicrosoft's
cloud-basedIntuneservice.
Keystore
WithAudioCodesNativeTeamsdevices,thecertificatekeysareencryptedonthedevicefile
system.
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CHAPTER1 Overview C435HD Users & Administrator's Manual
Device Certificate
AudioCodes NativeTeams devices areshipped with auniquecertificatewhich issigned by 
AudioCodesRootCA.
Data Protection
AudioCodesNativeTeamsdevicesrunAndroidwhichhasintegralproceduresforprotecting
andsecuringuserdata.
Debugging Interface
■TheAudioCodesNativeTeamsdevicesleverageSSHasadebugginginterface.
■AudioCodesrecommendsthatcustomersdisableSSHondevicesviaAudioCodes'Device
Manager(OVOC).
■AudioCodesrecommendschangingtheAdminpasswordfromthedefault,viatheTeams
AdminCenterorAudioCodes'DeviceManager(OVOC).
■Whenadevice-ormultipledevices-needstobedebugged,userscanenableSSHonit/
them,accessSSHwiththenewAdminpasswordforthedebuggingphase,anddisableSSH
oncedebuggingisfinished.
Android Security Updates
AudioCodesregularlyadoptsandintegratesAndroidsecurityupdates.
Forreference,seehere.
AudioCodes Root CA Certificate
ThefollowingfigureshowstheAudioCodesRootCACertificate.
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CHAPTER1 Overview C435HD Users & Administrator's Manual
-----BEGIN CERTIFICATE-----
MIIDMTCCAhmgAwIBAgIBATANBgkqhkiG9w0BAQsFADAfMQwwCgYDVQQK
EwNBQ0wx
DzANBgNVBAMTBlJvb3RDQTAeFw0wMDAxMDEwMDAwMDBaFw0zMDAxM
DEwMDAwMDBa
MB8xDDAKBgNVBAoTA0FDTDEPMA0GA1UEAxMGUm9vdENBMIIBIjANBgkq
hkiG9w0B
AQEFAAOCAQ8AMIIBCgKCAQEA6GK495KUCXAm/UE17G4/cjnZN4LNaxYE
YzbfZL0a
EhgSKYt/LQ+iUcDhojsneusNgrcGkpwKklKsGsvGWmSRNULV01CW+TX2VJN7
3+hh
V0uzhyOIYAUhbDaoqNM6Kp5b7sJ1ew4Ig9kfd/ma9Czl5koESLlw/inLj/r+rD96
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CHAPTER1 Overview C435HD Users & Administrator's Manual
mUcPElWrKspv7Qy4I14fsK/yMArixRopTL1munVVPpSFM9Jh8IY3JHyr5CQJXK
Ks
EhGAJsnHaRqsR2Su3X/WtslgEF+cvP34pxhlhFL29nMfnaFATSS3rgGaFlSvl1ZS
esLMqkWjp9cqGYrvt7K61sYnvMMb+o/KbWqVokXb+Fr7bwIDAQABo3gwdjAMB
gNV
HRMEBTADAQH/MB0GA1UdDgQWBBQDXySn9hz15lDraZ+iXddZGReB+zBH
BgNVHSME
QDA+gBQDXySn9hz15lDraZ+iXddZGReB+6EjpCEwHzEMMAoGA1UEChMDQ
UNMMQ8w
DQYDVQQDEwZSb290Q0GCAQEwDQYJKoZIhvcNAQELBQADggEBAI0rUyw
ommWWJnH3
JOfKiS3+VnX5hJITZymvWanMXUz/6FonHccPXEBYTrUYwhiWx3dwELAFXDF
KkxMp
0KKWZ4F39cAOLRjqhzya+xUeeJ9HQZCXYAJ6XgvTfN2BtyZk9Ma8WG+H1hN
vvTZY
QLbWsjQdu4eFniEufeYDke1jQ6800LwMlFlc59hMQCeJTenRx4HdJbJV86k1gBU
E
A7fJT1ePrRnXNDRz6QtADWoX3OmN7Meqen/roTwvLpEP22nYwvB28dq3Jetl
QKwu
XC4gwI/o8K2wo3pySLU9Y/vanxXCr0/en5l3RDz1YpYWmQwHA8jJIu8rxdhr+VN
Q
Zv6R/Ys=
-----END CERTIFICATE----
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CHAPTER2 Setting up the Phone C435HD Users & Administrator's Manual
2 Setting up the Phone
Unpacking
When unpacking, makesure the items listed in thephone's Quick Guidearepresent and 
undamaged.
If  anything  appears  to  be  missing  or  broken,  contact  the  distributor  from  whom  you 
purchasedthephoneforassistance.
Fordetailedinformation,seethephone'sQuick Guideshippedwiththedeviceoravailable
fromAudioCodes.
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CHAPTER2 Setting up the Phone C435HD Users & Administrator's Manual
Device Description
Use thefollowing  graphics to  identify and  familiarizeyourselfwith  the device's  hardware
functions.
Front View
Thefrontviewofthephoneisshowninthefigureanddescribedinthetable.
Figure 2-1: Front View
Table 2-1: Font View Description
Item # Label Name Description
1RingLED Indicatesphonestatus:
■Green:Idlestate
■Flashingred:
Incomingcall(ringing)
■Red:Answeredcall
2LCDscreen LiquidCrystalDisplay
interactivescreenwhich
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CHAPTER2 Setting up the Phone C435HD Users & Administrator's Manual
Item # Label Name Description
displayscalling
information.
3NavigationControl/OK ■Pressthebutton's
upperrimtoscrollup
menus/items.
■Pressthebutton's
lowerrimtoscroll
down.
■Pressthebutton'sleft
orrightrimtomove
thecursorleftorright
(wheneditinga
contactnumberfor
example).
■PressOKtoselecta
menu/item/option.
4Voicemail Retrievesvoicemail
messages.
5CONTACTS AccessesthePeople
screen.
6ReturnsyoutotheTeams
homescreen.
7TRANSFER Transfersacalltoanother
party.
8HOLD Placesanactivecallon
hold.
9MENU AccessestheSettings
screen.
10 Kensingtonlock Allowslockingthedevice.
11 AlphanumericalKeypad Keysforentering
numbers,alphabetical
lettersandsymbols(e.g.,
colons)
12 Microphone Allowstalkingand
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CHAPTER2 Setting up the Phone C435HD Users & Administrator's Manual
Item # Label Name Description
listening.Thenetwork
administratorcandisable
itifnecessary.
13 Speaker Activatesthespeaker,
allowingahands-free
conversation.
14 Headset Activatesacallusingan
externalheadset.
15 Mute Mutesacall.
16 ▲VOL
▼VOL
Increasesordecreases
thevolumeofthe
handset,headset,
speaker,ringtoneand
callprogresstones.
17 ‘Back’key Returnsyoubacktothe
previousscreen.
18 USBport AllowsusingaUSB
headsetifnecessary.
Navigate to menus and select menu items by:
●Pressing the rim of the control button (upper, lower, left or right)
●Pressing the OK key on the control button
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CHAPTER2 Setting up the Phone C435HD Users & Administrator's Manual
Rear View
Theportslocatedontherearofthephonearedescribedinthetable.
Table 2-2: Rear View Description
Item # Label Description
1RJ-45porttoconnecttotheEthernetLANcable
fortheLANconnection(uplink-10/100/1000
Mbps).Ifyou'reusingPoweroverEthernet(PoE),
powertothephoneissuppliedfromtheEth-
ernetcable(drawspowerfromeitheraspareline
orasignalline).
2RJ-45porttoconnectthephonetoaPC
(10/100/1000Mbpsdownlink).
312VDCpowerjackthatconnectstotheACpower
adapter.
4AUX [RJ-11port]Usedasaserialconsoleportto
accessthephone'sterminal.
5Headsetjack,i.e.,RJ-9portthatconnectstoan
externalheadset.
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