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Isdn PriA Low Cost VoIP Reference Design for Consumer and Industrial Applications

VoIP Overview Tight and Fast
Features Easy to Use
Applications Easily Ported to any Environment
Supports key standards Compliance Testing
Broad Development and Debugging Environment

VoIP Overview

This VoIP solution combines best-of-breed technologies from Freescale Semiconductor, Mentor Graphics, Global Edge and TeleSoft International. The TeleSoft CompactSIP stack is integrated with the Mentor Nucleus RTOS & TCP/IP stacks together with the Global Edge codecs and ported to the Freescale Coldfire MCF5234/5 VoIP EVM to create a complete low cost VoIP reference design. The software components are designed specifically for embedded solutions and require a minimum of memory space and processor bandwidth. This efficient and cost effective solution has a low cost of manufacture and is ideal for OEMs and ODMs wanting to minimize their technical risks while accelerating time-to-market of their products.


Primary applications include IP Phones, Mobile Phones, PDAs, Set-top boxes, IP PBXs, ATAs IADs, Voice Gateways, Medical Instrumentation, Fire/Security, Factory Automation, POS CPEs and ATMs.


  • Best-of-breed technologies
  • Minimal memory space
  • Fast time to market
  • Standards compliant
  • Low manufacturing cost
  • Single highly integrated processor
  • No DSP required
  • ANSI C code for easy portation


The CompactSIP SDK from TeleSoft International is a highly optimized SIP stack solution that combines a very small memory footprint for high performance with no compromises on functionality and scalability. Space-efficient operation and superior performance are maximized due to use of hand-crafted parsers that avoid typical code bloat caused by parser generators.

Remote Access Concentrator


The Nucleus PLUS RTOS from Mentor Graphics Embedded Systems Division is a high performance micro kernel based real-time, multitasking operating system designed specifically for embedded applications requiring deterministic, real-time responses while consuming a minimal memory footprint.

Nucleus NET TCP/IP

The Nucleus NET TCP/IP stack from Mentor Graphics Embedded Systems Division is a feature-rich TCP/IP stack that is highly versatile, small, quick in execution and ideal for real-time, multi-tasking applications such as VoIP. Nucleus NET includes a sockets API for ease of adding a range of applications.

Global Edge

The voice codecs and analog functions from Global Edge Software are customized and integrated with the hardware and software modules to provide a clean and efficient VoIP solution.

TeleSoft CompactSIP Features:

  • RFC 3261 – SIP: Session Initiation Protocol
  • RFC 3262 – SIP Reliability (PRACK)
  • RFC 3263 – SIP: Locating SIP Servers
  • RFC 3264 – SDP Offer/Answer
  • RFC 3265 – SIP   Specific Event Notification
  • RFC 1321 – MD5: Message Digest Algorithm
  • RFC 2327 – SDP: Session Description Protocol
  • RFC 2617 – HTTP Authentication
  • RFC 2806 – URLs for Telephone Calls
  • RFC 2833 – RTP Payload for DTMF Dial Digits, Telephone Tones & Telephony Signals
  • RFC 2915 – NAPTR: Naming Authority Pointer
  • RFC 2976 – SIP INFO Method
  • RFC 3204 – MIME Objects for ISUP and QSIG
  • RFC 3489 – STUN: Simple Traversal of User Datagram Protocol (UDP) Through NATs
  • RFC 3550 – RTP: Real-Time Transport Protocol
  • RFC 3515 – SIP Refer Method
  • RFC 3581 – An Extension to SIP for Symmetric Response Routing
  • RFC 3665 – SIP Basic Call Flow Examples
  • DNS Query/Response

CompactSIP is tight and fast:

  • Support for methods, headers, and message processing is configurable to save memory.
  • Smallest configuration fits in less than 100KB.
  • Just-in-time parser avoids parsing headers not used by SIP stack or application.
  • Optimized handling of timers avoids high start/stop overhead.
  • Crafted parser eliminates parser-generator bloat.

CompactSIP is easy to use:

  • Low-level API provides complete control over all SIP functions and message content.
  • API supports multiple independent services including multi-homing.
  • Easy to add special method & header processing.
  • Separate SDP and SIP parsers.

CompactSIP ports to any environment:

  • Portable to all memory models, including flat, heap, pool-based, and mbuf or zbuf.
  • Object-oriented API supports direct function-call interface, inter-task and inter-cpu messaging.
  • Highly scalable – no built-in limits other than those required by the system itself.

CompactSIP provides a broad development and debugging environment:

  • Sample applications demonstrate usability of APIs.
  • Debugging features provide compile-time/run-time details for messages & event logging.

TeleSoft International is a US-based, leading provider of “Protocols for Developers” for telecom applications. We license source code Protocol Stacks for VoIP, PPPoA, PPPoE, ISDN, Q.931, Q.921, QSIG, ML-PPP, PPP, Frame Relay, T1 RBS, E1 CAS R2 & X.25 to OEMs and ODMs worldwide.

Note: Information in this datasheet is preliminary and subject to change.


Copyright - 2010 TeleSoft International Saturday, July 3, 2010


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