Hello,

I have a requirement to normalise a number to an international E164 inside Kamailio.

In my scenario I’m receiving a call from “a platform”, and then making a call out to the same platform. I’m then adding some services to that call (e.g. recording it) on the way through.

The problem is that sometimes the number I receive in the FROM field in the initial invite from “A platform” has 44 at the front, but no +. “A Platform” is then rejecting the call back in from myself, because the FROM field isn’t formatted correctly.

Scenario 1 – WORKS FINE – sometimes we see this.

PSTN -> FROM:07700900000 -> A PLATFORM -> FROM:07700900000 -> ME

Call Centre <- A PLATFORM <- FROM:07700900000  <- ME

Scenario 2 DOES NOT WORK – sometimes we see this.

PSTN -> FROM:447700900000 -> A PLATFORM -> FROM:447700900000 -> Aeriandi

Call Centre <- A PLATFORM <- FROM:447700900000 <- Aeriandi

Scenario 3 WORKS by fixing up the number by adding a +

PSTN -> FROM:447700900000 -> A PLATFORM -> FROM: 447700900000 -> Aeriandi

Call Centre <- A PLATFORM <- FROM:+447700900000 <- Aeriandi (ADD a PLUS)

So I’m investigating if it’s possible to fix up the number and add the + in Kamailio. Clearly I could detect if the number starts with 44 and change this to +44, but this seems very brittle (what about other international numbers) – it there a proper way to do this, or a standard module?

Unfortunately asking “A platform” to send me the “FROM” in a consistent format is not an option.

Many Thanks,

Daniel