Matrix SETU VFX44L, Системное руководство

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Matrix
183 SETU VFX88L
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VFX44L V1
System Manual
streams. There are two variations of this standard (G.729 and G.729
Annex A) that differ mainly in computational complexity; both provide
speech quality similar to 32-kbps ADPCM. It is described in the ITU-T
standard in its G-series recommendations.
GSM Codec:
This codec uses the information from previous samples in order to
predict the current sample. 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.
HTTP
Hyper Text Transport Protocol-The communications protocol used to
connect to servers on the World Wide Web.
iLBC Codec:
internet Low Bit Rate Codec (iLBC) is a royalty free narrowband
speech codec. It is suitable for VoIP applications, streaming audio,
archival and messaging. iLBC handles the case of lost frames through
graceful speech quality degradation. It is defined in RFC 3951. This
codec works on sampling frequency of 8KHz/16 bit.
IP
It is the ‘Internet Protocol’, Network layer protocol in the TCP/IP stack
offering a connectionless internetwork-service. IP provides features
for addressing, type-of-service specification, fragmentation and
reassembly and security. It is defined in RFC 791.
MAC
Media Access Control Address-The unique address that a
manufacturer assigns to each networking device.
• MAC is Media Access Control address in the form of 48-bit
number, which is unique to the LAN NIC (Network Interface Card).
• It is programmed into the card at the time of manufacture. IEEE
registration authority administers MAC address scheme for all
LANs which conform to IEEE, 802stds. Including both Ethernet
and token ring.
• Consists of two parts: 24-bit company id (manufacturer ID0 and
24-bit Extension ID (board ID).