COMtrexx® Business

Large ICT all-rounder with traditional interfaces up to 150 users

Flexible scalability through user-based licensing (up to 150 users)

Modern and transparent system

Optimised for the operation of the Auerswald D series

Roaming user function for setting up mobile workstations

Configuration and monitoring via COMtrexx Control Center

Your advantages in detail

COMtrexx Business - the one-stop solution - is available as the manufacturer-assembled solution for up to 150 users with up to 40 simultaneous calls. The integrated analogue gateway supports up to 20 analogue telephones, and an additional Ethernet interface can be retrofitted.

The most important facts:

  • modern and transparent user interface
  • flexible and scalable through a floating user licence model
  • licensable up to a maximum of 150 users
  • with the Zero-Touch of the latest generation, the registration of devices is fully automated
  • optimised for operation with COMfortel D-series terminals
  • integrated conference option with up to 10 conference rooms that can be used simultaneously
  • roaming user function for setting up mobile workplaces (alternating workplaces)
  • comfort functions such as CTI, MWI and BLF with the COMfortel D series
  • central caller lists
  • remote monitoring and backup via COMtrexx Control Center and Auerswald Remote Access

Mobile working is easily and securely supported by optional soft clients for computers, tablets and smartphones. The cost-effective COMfortel SoftPhone for voice and chat is available at the entry level. Those who need more extensive functions and more intensive integration into business processes will find the optimal UCC solution with PBX Call Assist.

Compatible products

Features & technical data

Everything you need to know about our products comes now. Scroll down for more information.

Comfort Features

  • Up to 40 parallel calls possible
  • Up to 150 users licensable
  • Automatic control centre (maximum 10 configurable)
  • Barred/approved numbers, 10 each for coming and going, total maximum 200
  • Call of any second destination in parallel to the registered primary device
  • Call data management with 18,000 data records
  • Call pick-up (e.g. from the integrated voicemail or from mobile app COMfortel SoftPhone)
  • Broker and mediate
  • Pickup
  • Protection against attacks by setting blocking lists (blocked IP addresses) and activating blocking times
  • Text before signalling (can be switched for groups and for the automatic switchboard)
  • Music on hold with switchable announcement text
  • Autoprovisioning for standard SIP phones1
  • Roaming user function
    • Enables individual users to log on and off at different telephones
    • Personal caller lists can be transferred to different workplaces
  • Centrally stored caller lists
    • User-specific caller lists are stored centrally in the system
    • Stored lists are available when a user logs on via the telephone
    • Access only possible via the user
  • Setting up groups
    • 64 call groups
    • up to 40 members per group
    • Fixed channels can be reserved for group calls
  • Logging in and logging out a user via a telephone by PIN dial-in
  • Registration of up to 160 terminals possible

SIP convenience features for standard SIP phones

  • SIP-BLF, Busy Lamp Field acc. to RFC 4235
  • SIP-MWI (Message Waiting Indication), monitoring of the central voicemail and fax boxes acc. to RFC 3842
  • Pickup pre-check2

Communication platforms

  • Up to 30 internal channels can be assigned simultaneously across all conference rooms
  • Up to 10 conference rooms with 10 internal participants each (audio)

Central address books

  • 2,000 contacts
  • Separate address books for departments and multi-company operation
  • Import of VCF and CSV files
  • Address book provisioning via LDAP

VoIP telephony

  • VoIP point-to-multipoint and point-to-point connection (SIP trunking)
  • Call forwarding on busy (CFB), no reply (CFNR), unconditional (CFU) at carrier trunk, configuration dependent
  • Call deflection
  • Transfer of customer-specific calling number information with outgoing calls (CLIP no screening)
  • High voice quality through optimised echo cancellation and wideband audio with G.722
  • Compatible to standard SIP telephones
  • SIP compliant with RFC 3261
  • Reservation of speech channels
  • Support of soft clients and COMfortel Softphone
  • VoIP-Codecs: G.711, G.722
  • Dynamic internal/external VoIP channels
  • Encryption of signalling/signalling (SIPS) and voice data (SRTP) for internal calls
  • Integration of external extensions (information on the location of the telephone is taken into account in an emergency call) and mobile clients

Voicemail and fax

  • Substitute function
  • Call acceptance and individual announcements depending on calling number, time and call type
  • Remote access of the voicemail boxes incl. voice guidance
  • Message and fax forwarding via e-mail
  • Up to 60 fax mailboxes, each with 500 messages per box
  • Up to 60 voicemail boxes, each with 500 messages per box
  • Maximum 8 channels can be used for voice and faxmail

UCC functions

  • Call journal
  • Instant messaging for a better sharing of information
  • Contact data for local users and out of external data bases
  • Platform independent (Windows, macOS, iOS, Android)
  • Presence management with automatic status detection
  • Alignment with MS Teams
  • Call setup and ending via the PC, incl. Outlook plug-in
  • Screen sharing for convinient cooperation
  • Softphone-functions for Windows, Android und iOS
  • Up to 150 users can be licensed

COMfortel SoftPhone

  • Softclient for the base functionality SIP telefony and messaging
  • Secure and simple PBX connection from anywhere via Auerswald cloud service
  • Softphone for Windows, iOS and Android

Software interfaces

  • Access address books via LDAP
  • Support of basic CTI function via action URLs3

Installation and maintenance

  • Support of the COMtrexx Control Centre for secure remote control & backup management

Unlockable options

  • User licence: Activates all functions of the Soft PBX and is required for linking users to a device. One licence must be activated for each active/registered user on the system4
  • PBX Call Assist
  • System activation (necessary for operation of the system)

Module connection options

  • Extension with analogue gateway ports possible (up to a maximum of 20 ports)
  • Extension by one Ethernet port possible


  • The COMtrexx solutions can only be used in combination with floating user licences. You can obtain these and other licences from our authorised sales partners. Please note that additional services such as software maintenance and function extensions may cause additional costs.
1 Supported for telephone models D-600/D-400/D-210/D-200/D-110/D-100 and WS-500S/M IP-DECT systems. Also partially supported are telephone models from other manufacturers such as Yealink and Snom
2 Is only supported for the telephone models D-400/D-600 and D-210/D-200 in operation with an extension.
3 Is supported for the telephone models D-600/D-400/D-210/D-200/D-110/D-100 from Auerswald
4 The licence can be used by several users ("floating"), provided that the total number of active users corresponds to the total number of licences in the system.

Trunk lines 1



VoIP channels (SIP acc. RFC 3261), point-to-multipoint/point-to-point connection (SIP trunking)

80 80

VoIP codecs

G.711, G.722 and G.729

User connection 1



VoIP subscribers

0 - 150 150

VoIP channels (SIP acc. RFC 3261)

0 - 80 80

VoIP codecs internal

G.711, G.722 and G.729

Voicemail and fax system



Voicemail channels

8 8

Fax channels

8 8

Voicemail boxes / fax boxes

60 60

Fax standard

T.30/T.38 acc. to ITU-T

Additional connections 1



Ethernet ports 10/100 Base-T (10/100 MBit/s, twisted pair)

1 2

Analogue audio output for announcements (e.g. a/b Audiobox)

4 4

Module slots


Technical data



Operating voltage

230 V ±10 %, 50 Hz

Power consumption

5 W min. | 65 W max.


plastic, metal angles for 19" rack mounting

Dimensions (w x h x d)

325 mm x 88 mm x 240 mm

Weight (w/o modules)

approx. 1,700 g



Supported operating systems

Windows 7/8/10, macOS, Linux

  • 1 Possibly depending on the configuration of the telephone system
  • 2 All VoIP channels are freely configurable between internal, external and dynamic

Delivery Scope

  • Base unit
  • Ethernet cable
  • Operating manual


COMpact 4FXS Module

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Top Sellers

Sales Configurator (SC)

- the easy way to the right system

Customer requirements for communication solutions are constantly increasing and with them the complexity and scalability of ITC systems. Project planning therefore takes up more and more time. Here, the free Sales Configurator offers a simple and fast solution. It gives you the opportunity to efficiently plan communication solutions and create project planning proposals.

Sales Configurator (SC)