Switching Systems and Call Centers
IMG95
VoIP IVR
IMG95 is a VoIP device belonging to a family of IMG devices.
All IMG family devices are developed for use in NGN (Next Generation Network).
IMG95 is the first domestic VoIP device from Iritel.
Application
- IMG95 is used to support service 95 (exact time speaking service) in Telekom Srbija
- IMG95 is a contemporary IVR (Integrated Voice Response) system with adequate number of voice channels (VoIP channels to IVR channels ratio is 1:1)
- IMG95 is connected to NGN via SIP protocol
- Media transfer is performed using RTP/RTCP protocol
- Exact time is established using NTP protocol
Configuration
Exact time speaking function is supplied by Exact Time System – STV which consists of two IMG95 devices and two switches connected in order to increase the reliability of a system. STV is working in active/stand-by mode and fulfils the "no single point of failure" criteria. STV is maintained from IT network by computer NU.
IMG95 contains printed boards:
- IMG – basic board with embedded Linux
- PFC – DSP processors for voice packing
- VMU – voice machine unit
Basic technical data
| ITEM | DATA |
| Traffic | 86 Erl (up to147 Erl) |
| Number of VoIP channels | 120 (up to 200) |
| BHCA (Busy Hour Call Attempts) | around 10.000 (17.000) |
| Connection to IP/MPLS network | 4 x 100 BaseTx Fast Ethernet IEEE 802.3u |
| Codec's | G.711, G.729 |
| VQE (Voice Quality Enhancements) | EC, VAD, PLC, CNG,AJBM |
| Power supply | internal converter 220 V~ to 48V= |
| Dimensions | rack 19'' wide, 1 U high, 300 mm deep |
| Weight | around 2 kg |
IP/MPLS network connections:
- ETH – IT network connection (maintenance, ntp)
- SIGN – SIP signalization
- DATA – RTP/RTCP media transfer
- VMU – voice machine unit control
VQE techniques are:
- EC – echo cancelation
- VAD – voice activity detection
- PLC – packet loss concealment
- CNG – comfort noise generation
- AJBM – adaptive jitter buffer manager
Operation and maintenance
Operation and maintenance is executed from IT network by computer NU.
NU functions are:
- statistics – data on number of calls, duration, etc. is gathered every 15 minutes
- alarms – heavy, medium and light alarms are gathered and displayed
- archives – all gathered data are archived in daily reviews (15 min. statistics, from-until statistics, alarms)
- web – IMG95 devices have their own web pages with configuration data
- docs – help documentation