Telesis PX24 IP PBX Business Phone System
Design and manufacture IP PBX Business Phone System, Switching System, VoIP Gateway, and Signaling Converter  

Applications with Telesis Systems

IP Telephony

Telesis IP Telephony Systems (like Hybrid IP PBX systems and VoIP Gateways) offer significant cost and performance advantages. The obvious advantage of IP Telephony is cost savings. Sending packets of data via an internet network is cheaper than making voice calls over a traditional circuit switched telephone network. A Telesis IP Telephony system combines VoIP technology, TDM technology, and Telephony features altogether. Telesis IP Telephony solutions are engineered to:

  • provide quality of voice over internet
  • secure calls
  • provide IP-TDM gateway capability
  • provide softswitch capability
  • include integrated H.323 gatekeeper
  • include integrated SIP registrar
  • manage the traffic efficiently
  • provide alternate TDM routes if IP trunk calls fail due to network unavailability
  • allow to record VoIP calls (conversations) to recorded bi-directionaly
  • support numerous system and user features
  • be scalable for future expansions
  • have open architecture for future implementations

Big savings can be achieved by using the Telesis IP Telephony system to:

  • bridge distant corporate offices
  • access long distance call operator rather than paying high traditional call charges
  • run the business effectively with
    • SIP users local or remote, wired or wi-fi
    • H.323 users local or remote, wired or wi-fi
    • easy PMS integration
    • easy IP DECT integration
    • easy external call processing server integration

Another advantage of a Telesis IP Telephony system is to increase the productivity of employees. Employees would be able to communicate without incurring greater communication costs in the process.

A Telesis IP Telephony system is equipped with well-known industry standard codecs for high quality communication as well as low bandwidth usage. It is capable of supporting multiple codecs and ready for adding more as technology emerges and popularity changes. Another key technical requirement for the VoIP quality is the echo cancellation. The echo canceler of a Telesis IP Telephony system is AT&T certified and exceeding G.168:2002 requirements. It is better than industry standard cancelers under the most important and difficult conditions like double-talk and the presence of background noise.

Considering the security issue, a Telesis IP telephony system provides greater protection than traditional phone systems. Furthermore, the ability to encrypt voice via IP call by using 256 bit AES (Advanced Encryption Standard) provides an advantage for security compared to existing telephone systems.

PBX (Private Branch Exchange) 

Telesis systems offer a wide range of applications for private telephone exchanges. Advanced features across a number of different interfaces make Telesis systems, the ideal choice for organizations seeking to install, expand, or upgrade their PBX (PABX) systems.

With hundreds of programmable features, Telesis systems make traffic management highly efficient and versatile.  The convenience of dealing with all-in-one standard software allows the user to support as many features as desired, up to the maximum capacity: thus, an organization`s capacity can grow  without necessarily updating the software.  Another aspect of the system?s software is an advanced algorithm for creating routing tables, including an option for  Advanced Least Cost Routing (LCR).

Some of the services offered by Telesis PBX and IP PBX systems are:

  • ISDN supplementary services
  • Many analog subscriber services
  • Many digital subscriber services
  • Programmable cadences
  • Programmable frequencies for tones
  • Real-time charging facility
  • Generating of  call and log records
  • LCR (Least Cost Routing)
  • Credited Subscriber
  • Detailed charging options
  • Selection filters for call records
  • Unlimited subscriber categories
  • Flexible numbering
  • Hotel-specific features
  • Conferencing
  • Recorded announcements
  • Voice Mailing
  • Bi-directional recording of conversation

Central Office

As a central office switch, the Telesis X1 serves as a service switching point (SSP). The switch is stored-program controlled. SSP and routing functions are integral parts of its operating system. The X1 central office can be connected to several adjacent SSP and STP switches. 

The X1 central office also supports many signaling systems of legacy PSTN networks. Based on a very powerful industrial micro-computer, the X1 has a call-completion success rate of over 99.999% at 300,000 BHCA (Busy Hour Call Attempts). Redundancy of the control and switching subsystem is provided by a duplicated micro-computer, memory elements, switching array, service circuits, HDLC controllers, and administration terminal interfaces.

Key features of the Telesis X1 central office are:

  • Scalability from one to tens of E1 interfaces to connect to adjacent exchanges
  • SSP and STP support
  • Capacity for up to 14,400 subscribers with long loop drive
  • Caller ID (according to ETSI FSK standards) for analog subscribers
  • Numerous digital and analog signaling protocols
  • Detailed records of originating and terminating calls
  • Traffic measurement
  • Monitoring and analysis of signaling
  • Numerous subscriber services

Transit Switch

As a transit switch, the Telesis X1 is a scalable carrier-grade circuit switch. The switch is based on a very powerful industrial micro-computer and has a call-completion success rate of over 99.999% at 300,000 BHCA (Busy Hour Call Attempts). Redundancy is provided by a duplicated micro-computer, memory elements, switching circuits, service circuits, HDLC controllers, and administration terminal interfaces. Supporting both legacy and new digital networks, it enables operators and carriers alike to run their networks smoothly and facilitates their later adaptation to new-generation networks.

The SS7 subsystem of the Telesis X1 transit switch provides resources for generating and responding to Signaling System No. 7 (SS7) messaging. The X1 may serve as a service switching point (SSP) and signaling transfer point (STP). Key features of the Telesis X1 are:

  • Carrier-grade switching
  • Scalability from two to 120 E1 interfaces
  • SSP and STP support
  • Capacity for up to 120 SS7 links
  • Basic error control for land lines / preventive cyclic retransmission (PCR) for satellite connections
  • Numerous digital and analog signaling protocols
  • Interworking capability combined with unique protocol conversion capabilities
  • Detailed records of originating and terminating calls
  • Traffic measurement
  • Monitoring and analysis of signaling

The Telesis X1 transit switch has a powerful routing capability that allows operators and carriers to define routes and their alternates for a large number of branches.

Local Exchange and Access Network

V5.2 protocol implementation in Telesis systems follows ETSI standard ETS EN 300  347 (Version 2). The implemented protocol covers both LE (Local Exchange) and AN (Access Network) protocols and supports analog telephone access (PSTN) and ISDN basic-rate access.

One unique feature of Telesis systems is their versatility: the V5.2 LE protocol and V5.2 AN protocol and other signaling systems can co-exist within one switch, such that:

  • Some subscribers may constitute an AN of a dedicated local exchange
  • Some E1 interfaces may utilize the V5.2 LE protocol so that other ANs may be connected
  • Some subscribers and trunks may continue to operate in conventional mode

With the interworking capability of Telesis system algorithms, Stillink V5.2 protocol converters enable an exchange to adapt its existing equipment to the V5.2 protocol. This means Stillink V5.2 protocol converters:

  • allow V5.2 AN systems to be connected to LEs that do not support V5.2
  • allow AN vendors to facilitate the connection of their V5.2 ANs to existing non-compliant LEs

You may visit for further details about Stillink V5.2 protocol converters.

Channel Bank

Telesis`s PX24X is ideal for highly advanced but cost-effective channel bank solutions. The PX24X is an intelligent channel bank that can interface with E1 ports of any switch, VoIP server, PBX to interconnect FXS, FXO, and E&M ports. Signaling types and protocols supported by the PX24X`s E1 interfaces are:
Channel-Associated Signaling (CAS)
  • Single-bit E&M emulation
  • Two-bit ITU-T R1
  • Two-bit ITU-T R2
  • Many variations of signaling types (such as CL-1B, OCL-1B, TCL-1B, SL/ZSL, SLM) widely employed in CIS countries
Common-Channel Signaling (CCS)
  • DSS1 (EuroISDN in the TE direction)
  • DSS1 (EuroISDN in the NT direction)
  • ECMA QSIG (in the TE direction)
  • ECMA QSIG (in the NT direction)
  • ITU-T and ETSI Signaling System No.7 ISUP
At its maximum capacity, the PX24X Channel Bank can have up to four E1 interfaces with 120 voice channels to interconnect FXS, FXO, and E&M ports. For various capacity requirements, it may be configured as:
  • four E1s : 120 voice channels
  • three E1s : 90 voice channels
  • two E1s : 60 voice channels
  • one E1 : 30 voice channels
Key features of the Telesis PX24X Channel Bank are:
  • Scalability from one to four E1 interfaces
  • Fractional or full E1
  • Clock source could be configured as internal or external
  • Scalability from 30 to 120 voice channels
  • Supports various signaling types and protocols
  • Mixed use of FXS, FXO, and E&M ports
  • Modular architecture allowing custom-configured channel banks to fit the exact requirements
  • Address transmission as Overlap or Enbloc 
  • Internal power supply
Available voice cards are:
  • 16-channel FXS card (with Caller ID)
  • 8-channel FXO card
  • 4-channel 2-wire E&M card
  • 4-channel 4-wire E&M card

Signaling Converter

The signaling-protocol conversion capability that is standard in all Telesis systems, enabling connections to be established with a wide range of telecommunications networks, is also available in stand-alone formats: the Telesis Stillink 200 and Telesis Stillink 800. They give service providers the advantage of being able to add advanced services to their networks more quickly and at lower cost than would be the case if they upgraded their existing core network switches. Stillink signaling converters are ideal for customers who seek:

  • Legacy equipment life extension
  • Cost-effective protocol support for older-generation switches
  • Easy and fast installation and integration without replacement of old switches
  • Easy maintenance
  • Adaptability to new protocols

The Stillink products are fully non-blocking and can handle very high call volumes without congestion. For further details, you may visit

VoIP and Access Gateway

Stillink digital VoIP gateways integrate both packet and circuit switching technology. A Stillink digital VoIP gateway featuring an integrated gatekeeper and registrar provides an economical way for administrators to manage a central database of phone numbers without the expense of a separate-box gatekeeper or registrar solution. 

Stillink digital VoIP gateways are also with the PSTN by-pass feature that operates not only for IP network failures but also for preselected routes. Alternate routing capability provides automatic fall back to the PSTN if the IP network is unaccessible. Furthermore, enterprises keep their present E1 connections to the PSTN while migrating to VoIP technology.

For further details, you may visit 


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