• VPP SIP Ladder Diagram
    VPP SIP Ladder Diagram
  • VoIP & VoLTE Quality Testing
    VoIP & VoLTE Quality Testing
  • Analog to SIP Voice Quality Testing
    Analog to SIP Voice Quality Testing
  • VoLTE Quality Test using Anritsu MD8475A Emulator
    VoLTE Quality Test using Anritsu MD8475A Emulator

voip & volte nodes

VPP - VoIP behavior in test and live networks

VoxPort Packet (VPP) is a new generation SIP end-point providing VoIP signal generation and measurement capabilities within the IP domain or between the IP domain and the analog domain.

Managed by MultiDSLA Controller software, VPP brings standard based voice quality testing methods to VoFi, VoIP or VoLTE networks.

VPP acts a reference VoIP end-point designed to help Enterprise Network Managers, Product Developers, Voice Engineers validate, troubleshoot, analyze and report on the Quality of Experience delmivered to their customers and users.



Detect, Reproduce, and Analyze VoIP behavior in both test and live networks

VPP generates real voice calls over a VoIP network, analyzing voice quality and other parameters affecting users’ perception of performance. Optional built-in packet impairment generation and managed codec rate changes combine to make VPP+ (VoxPort Packet+) a simple and effective way to understand, manage and even reproduce VoIP network behavior.

Test calls can be made with or without SIP server registration.

The VPP encodes and transmits real speech samples. It also receives and decodes the speech. All codecs that matter are supported, including EVS.

MultiDSLA Controller manages the configuration, runs the test call plan and stores the measurements for reporting and analysis.

VPP is highly flexible and can be configured in many ways to address specific test requirements.

With VoxPort Packet you have the tools to examine, understand and even reproduce VoIP network behavior.

Discover your true MOS
Try MultiDSLA... free !

Better validate or predict your Voice Quality of Experience

Overlays are a unique way to easily reproduce and understand voice quality impairment.

VPP+ has two overlay modes:

The Packet Impairment Overlay defines a precise pattern of packet impairments.

The Rate Change Overlay defines transmit rate changes or Codec Mode Requests (CMR) synchronised to speech transmissions.

Both of these overlays may be constructed by the user with a graphical overlay designer.

Alternatively, the Packet Impairment Overlay may be based on a capture from a live network.


Title/Description Download
MultiDSLA Nodes Spec Sheet - English
List and descriptions of MultiDSLA Nodes Specs

2.1 MB


VPP Technical Specifications

Technical Specs

VoxPort Packet


VoxPort Packet+


MultiDSLA Controller Compatibility v5.0 and above
Codec support

G.711, G.729, G.729A, G.729B, G.723.1, G.722, G.726, iLBC, Opus*, AMR NB & WB with DTX, GSM EFR*, 8k, 16k, 32k linear pcm

Frame sizes 5, 10, 20, 30, 40, 50, 60ms
according to codec

User defined static jitter buffer

Call capacity


10, 20 or 30

Network interface defnable for each call
IPv4 & IPv6 support
SIP Port definable
SIP call setup and teardown: RFC 3261
RTP: RFC 3550
SDP: RFC 4566
Digest Authentication: RFC 2617
SIP-less – Call established to user defined IP address and ports
Impairment generation

Random packet loss %

User defined packet loss

Random jitter within range

User defined jitter 

AMR codec rate changes within call
Packet capture

Controls Signalling


 Test signal generation

Normal - Voice file only

Complex - Voice + background noise files

 Operating System support

64 or 32 bit

Windows 8 & 10 Professional

Windows 2012 R2 and 2016 Servers

(Run as Windows Service)


Floating or Static

Transferable within MultiDSLA Controller