Paradyne JetFusion 2008, User Manual

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Set Jitter Delay
Inter-arrival jitter is the difference in relative transit time for two packets. It is
the difference between the packet's RTP time-stamp and the receiver's clock at
the time of arrival of the packet.
As shown in the equation below, this is equivalent to the difference in the
relative transit time for two packets: the relative transit time is the difference
between a packet's RTP time-stamp and the receivers clock at the time of
arrival, measured in the same units.
If Si is the RTP time-stamp from packet i and Ri is the time of arrival in RTP
time-stamp units for packet i, then for two packets i and j, D may be
expressed as:
D(ij) = (Rj
−
Ri)
−
(Sj
−
Si) = (Rj
−
Sj)
−
(Ri
−
Si)
The interval jitter is calculated continuously as each data packet i is received
from source SSRC
−
n, using this difference D for that packet and of the
previous packet i
−
1 in order of arrival (not necessarily in sequence),
according to the formula:
J = J + ({D (i
−
l, i)}
−
J)/16
The Jitter Delay should be set only by a Network Administrator. To set jitter
delay (0 to 50 ms
−
default is 0 ms), follow the steps below.
1
Type
“J”
on the Voice Configuration menu (Figure 4.27) to select Set Jitter
Delay. The IAD prompts you to enter the number of milliseconds to delay.
2
Type the delay value and press Enter. The IAD saves the jitter delay and
displays the Voice Configuration menu so you can continue with other
voice path configuration.
Display Jitter Delay
To display the current jitter delay value, type
“D”
on the Voice Configuration
menu (Figure 4.27). The IAD displays the current value.:
Press any key to display the Voice Configuration menu and continue.
Voice Port Settings
To display the Voice Port Configuration Menu (Figure 4.48), type
“P”
on the
Voice Configuration menu (Figure 4.27). Voice port settings should be
changed only under certain circumstances. Please consult your service
representative prior to changing these setups.
Figure 4.48 Voice Port Configuration Menu