ZyXEL Communications IES-1248-51A, User Manual

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Chapter 1 Introducing the IES-1248-51V
IES-1248-51V User’s Guide
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Quality of Service (QoS)
The IES-1248-51V supports IEEE 802.1p QoS (Quality of Service) network traffic
prioritization for H.248 and RTP traffic, as well as DSCP (Differentiated Services
Code Point) and ToS (Type of Service) tagging.
Voice Compression and Decompression
The IES-1248-51V supports the following voice codecs.
• G.711 A-law
• G.711 µ-law
• G.723.1
• G.726 (40, 32, 24 and 16 kbps)
• G.729AB
Out-of-Band POTS Signaling
As well as transmitting and receiving voice band data, FXS and FXO can
communicate using out-of-band signals.
Call Progress Tones
The IES-1248-51V can provide the following tones to connected telephones:
Table 1 Out-of-Band POTS Signaling
SIGNAL DESCRIPTION
Off Hook FXO intends to start a call
On Hook FXO terminates the call
Flash Short on-hook “tap” for special call functions.
Pulse Dial Dialing method using an interrupted signal.
Ring AC power signal from FXS port indicating a phone call attempt
from remote party.
Tip/Ring Reversal FXS port reverses the voltage between the tip and the ring
Metering Tone FXS port sends a 12 /16kHz out-of-band sine wave for payphone
use.
Table 2 Supported Tones
TONE INDICATION
Dial tone A line is available for use.
Busy tone The dialed number is unreachable.
Congestion tone There are not enough resources to handle a call.
Ringback tone The remote party’s phone is ringing.