sample, thereby resulting in total required bandwidths of 32,000, 24,000, or 16,000 bps.

G.729 The G.729 and G.729A conjugate structure algebraic code excited linear prediction (CS-ACELP) coding scheme also compresses PCM using advanced codebook technology. It uses 8000 bps of total bandwidth.

G.723 The G.723 and G.723A multipulse maximum likelihood quantization (MPMLQ) coding schemes use a look-ahead algorithm. These compression schemes result in a required bandwidth of 6300 or 5300 bps.

GSM GSM (Global System for Mobile communications) is a cellular phone system standard popular outside the USA. The speech signal is divided into blocks of 20 ms. These blocks are then passed to the speech codec, which has a rate of 13 kbps, in order to obtain blocks of 260 bits.

Note

The network administrator should balance the need for voice quality against the cost of bandwidth in the network when choosing CODECs.

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LevelOne VOI-7011, VOI-7010 user manual

VOI-7011, VOI-7010 specifications

LevelOne has made a significant mark in the field of networking solutions with its innovative products, including the VOI-7010 and VOI-7011. These devices are designed to cater to the growing demands for VoIP (Voice over Internet Protocol) applications, particularly in enterprise settings where reliable and clear communication is paramount.

The LevelOne VOI-7010 and VOI-7011 are advanced VoIP gateways that convert traditional analog signals into digital voice data, allowing businesses to leverage their existing analog phones while transitioning to a VoIP infrastructure. This capability ensures that businesses can maintain their current telephone setup without incurring the high costs associated with a complete overhaul.

One of the key features of the VOI-7010 and VOI-7011 is their comprehensive support for both FXS and FXO interfaces. The FXS ports are designed for connecting analog phones, allowing them to make use of VoIP services, while the FXO ports connect to traditional telephone lines. This dual-functionality makes these devices versatile and suitable for a variety of communication needs.

In terms of technology, both the VOI-7010 and VOI-7011 support a range of high-quality audio codecs, including G.711, G.726, and G.729. This flexibility in codec support ensures that users can experience optimal voice quality and bandwidth efficiency, meeting different network conditions and requirements.

Both models also come equipped with advanced features like echo cancellation, which enhances call clarity by reducing background noise and minimizing echoes during conversations. Additionally, they support SIP (Session Initiation Protocol) for signaling and management, making them compatible with various VoIP service providers.

The VOI-7011 model further extends the capabilities of the VOI-7010 by offering enhanced security features, including firewall and NAT traversal. These features help protect the system from unauthorized access and ensure secure communication over the network.

In summary, the LevelOne VOI-7010 and VOI-7011 are robust VoIP gateways that facilitate the transition from traditional phone systems to modern VoIP solutions. With their support for multiple interfaces, high-quality codecs, and security features, they provide businesses with a reliable and efficient communication platform, paving the way for future advancements in voice communication technology.