This is a static archive of our old Q&A Site. Please post any new questions and answers at

Analyze roaming voip traffic


Hi all,

I am having trouble to analyze VOIP in roaming mode. What is the link between the original number anf the one used for roaming. Example: If my sim card is Swiss and I go abroad to Germany. If I call another number in Switzerland I can see a German number used. How to link that roaming number to my Swiss number.


asked 10 Oct '17, 03:55

zmaktouf's gravatar image

accept rate: 0%

How is VoIP related with a SIM card? Do you use VoLTE? And where do you capture the signalling traffic?

What often happens is that mobile operators use 3rd party services for international calls, and these often change the calling party number to evade regulatory requirements. So the mapping between your Swiss calling number and the calling number which the called party can see is nothing predictable. In the cost-cutting world we live in these days, it is a small holiday if the called party can see the real number of the calling party in an international call.

(11 Oct '17, 04:40) sindy