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VoIP: Service Providers & Enterprise
Entropia™ II

Entropia™ II is part of the family of products targeted at gateways that bridge traditional circuit and cell/packet switched networks. A single Entropia™ II chip supports up to 336 full-duplex voice connections with (or without) compression, echo cancellation (on TDM side), comprehensive tone/announcement processing and telephony features as well as complete AAL1, AAL2, and IP support.

The main function of Entropia™ II is to provide format conversion and switching between individual voice streams, flowing across packetized voice and conventional circuit switched voice highways. Each voice channel from the TDM side is echo canceled, compressed, and packetized for transmission over the packet network. In the reverse direction, each packetized voice channel from the packet network is buffered for de-jittering, decompressed, and terminated at the TDM interface. The Entropia™ II interfaces to the circuit switched networks through a standard-compliant TDM interface and to the packet network through a UTOPIA level-2 interface for cells or a POS-PHY interface for variable size packets.

The Entropia™ II supports layer 2/3 control plane traffic transport over the packet network (for example, CAS signaling for voice over AAL2). Control plane messages received from the packet network are split and routed to the host processor, while user plane traffic is scheduled for voice processing and then routed to the TDM highway. Voice traffic from the TDM highway is merged with control plane traffic from the host processor for transmission to the packet network. Additionally, a single Entropia™ II supports 4:1/8:1 over-subscription on the ATM (AAL2) interface, where type 3 and refresh messages from up to 4x336/8x336 channels are transported to-and-from the host processor to enable call setup and tear-down functions.


336 channel, Low Power


336 channel with advanced features,
Low Power



96 channel voice over packet, Low Power


High-density and high-integration voice/data convergence product that bridges circuit and packet switched networks
  • Up to 336 voice channels per chip
  • Cascadable to OC3 capacity and beyond
  • Fully compliant to ITU-T and ATM forum standards
Performs all of voice processing, telephony, and networking functions in one chip
Low power dissipation, 3.3 Watts
Voice compression with echo cancellation
  • Up to 336 channels of PCM with ATM AAL1
  • Up to 336 channels of PCM/ADPCM with IP and ATM AAL2
Echo cancellation
  • Provisionable from 8 to 128 ms of echo cancellation
  • Meets G.165 and G.168 ITU-T standards
Telephony features
  • Voice activity detection (VAD)
  • Silence insertion descriptor (SID) support
  • Comfort noise generation (CNG)
  • Per channel A-law and µ-law support and conversion
  • Automatic detection of fax/data modem calls and revert to 64 kbps PCM
  • Comprehensive tone detection and processing for national and international standards
  • Message Announcement support
Networking features
  • Complete user plane AAL1/2/5 and IP support
  • Independent POS-PHY and UTOPIA interfaces
  • Support for control plane traffic transport (AAL2 type 3 messages, OAM cells, TCP, RTCP, etc.)
  • Split and merge of AAL1/2 control and management traffic with user plane traffic
  • 4:1 over-subscription support on the packet interface
  • Support for SSSAR and SSTED
Vocoder and feature selection on a per-call and per-channel basis
Host API provides easy system integration
Extensive management and performance monitoring
Support for in-operation and standby system diagnostics including self tests
Support for redundancy
Intelligent on-chip power management

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