Internet Telephony PBX System with ISDN Support IPX-1800N Datasheet Manual Firmware FeaturesSIP featuresStatic/Dynamic registrationCall-based MD5 authenticationNAT traversal for clientsOutbound proxy with or without WANUp to 5 SIP trunks for inter-PBX SIP trunkingInter-proxy call hand-offAuto-config for SIP IP Phones/ ATA30 registration / 30 voicemail / 10 concurrent callsAuto NAT Discovery and TraversalBuilt-in STUN ClientRTP ProxyRTP Port Range DesignationRelational ProvisionLogical Partition/Relation between Users and TrunksLogical Provision on Outgoing and Incoming Calling Search ScopesRich Dial-Plan Expressiveness thru Route PatternsUser Privilege Propagation Over Intra-TrunksObject-Oriented Provisioning ParadigmPBX FeaturesSupport call hold, call waiting, 3-way call conference with feature phonesBuilt-in in-line call transferUnconditional, unavailable, busy call forwardPer-calling-number forward and rejectionCall Privilege GroupingGroup-based call pick-upCall-parkingUp to 8 parties multi-room meet-me conferenceFXO disconnection tone detectionIn-band/RFC2833/SIP-INFO DTMF TranslationQoS supportLifeline / Emergency call supportMusic on holdOutbound 900/0204 900/0204 FREE blockingBlacklist of Number PatternsAuto AttendantConfigurable IVR promptsKey to reach operatorWork time IVR3-layer Auto AttendantTimeout interval and timeout actionMusic on ringing extensionsForward to voice mail on no-answerVoice MailUser PIN450 minutes recording timeMWI notificationE-mail notificationPersonal reception on unavailability and busyVoicemail forwardingVoicemail to email