AllowedAddresses filter on SIP Trunk

Nestor Morales
Fri, 10 Apr 2026 15:08:13 +0000
Telephony

Hello,

I’m trying to increase security for my SIP trunk so I just allow receiving calls coming from a specific IP. My understanding is that I can use the AllowedAddresses field for that.

So I have the following:
$ lk sip inbound list
Using default project [******]
┌─────────────────┬───────┬───────────────────────────────────────────────┬──────────────────┬────────────────┬────────────────┬────────────┬─────────┬──────────┐
│ SipTrunkID │ Name │ Numbers │ AllowedAddresses │ AllowedNumbers │ Authentication │ Encryption │ Headers │ Metadata │
├─────────────────┼───────┼───────────────────────────────────────────────┼──────────────────┼────────────────┼────────────────┼────────────┼─────────┼──────────┤
│ ST_****** │ Tests │ +34*********,*********,+34*********,********* │ 1.2.3.4/32 │ │ │ DISABLE │ │ │
└─────────────────┴───────┴───────────────────────────────────────────────┴──────────────────┴────────────────┴────────────────┴────────────┴─────────┴──────────┘

With this configuration, I would expect a call to be rejected, but I am still receiving it. Am I doing anything wrong?

5 posts - 3 participants