Technical data

Technical Data HG 3570/3575
EN4442EN00EN_0001
© 2007 Siemens AG
Siemens
46
● Jitter Buffer - fixed size, adjustable between 0 and 210 ms
● Network Management Support
● SNMP Agent, SNMP Version 2, MIB2, Private MIB for Audio Stream Control
● Voice delay (mouth to ear)
The delay is made up of the following components:
● Time for filling the voice packet (SampleSize, Encoding Time):
Sample size - possible values: 20, 30, 40, 60 ms
● Implementation-specific delay on the transmission end
● Delay caused by the transmission between the HG 3500/75 gateways in the IP
network
● Size of active Jitter Buffer:
Jitter Buffer
● In legacy mode the average delay corresponds to the value set.
The actual value is within the range [0 .. set value + 40 ms]
If fax/modem signals or ISDN data are being transmitted, the average delay
corresponds to the set value + 30 ms.
The actual value is within the range [0 .. set value + 70 ms]
● In static mode the network jitter to be compensated is configured. An additional 13
ms jitter buffer depth is added to compensate for the system’s own jitter. In other
words, the average delay corresponds to the set value + 13 ms.
The actual value is within the range [0 .. set maximum value + 13 ms]
● In adaptive mode it is best to take the set start/average value + 13 ms to calculate
the average delay.
The actual value is within the range [0 .. set maximum value + 13 ms]
● Implementation-specific delay on the receiving end
The implementation-specific delay on the sending and receiving ends is represented as a total
value. This value depends on the codec type used (G.711/G.729) and, in the case of G.711, it
depends on whether voice, fax/modem signals or ISDN data is being transmitted. The values
are average values from a sequence of measurements. The actual values can be up to 5 ms
lower or higher than the average.
These values may change in the course of fault correction and functional expansion. This does
not always lead to a preliminary announcement or an immediate update of the manual.