I recently wanted to setup an asterisk server using Twilio as the phone provider. There wasn't much resource out there, but from what I did find it wasn't up to date or working.
I found something by Jordan Cook, however it wasn't for chan_pjsip, so I updated it and came up with the following:
[twilio]
type=endpoint
context=from-twilio
from_user=twilio
disallow=all
allow=ulaw
auth=twilio
aors=twilio
[twilio]
type=auth
auth_type=userpass
password=password
username=twilio
[twilio]
type=aor
max_contacts=10
; north american gateways - currently the only ones in use
[twilio-1]
type = identify
endpoint = twilio
match = 107.21.222.153
[twilio-2]
type = identify
endpoint = twilio
match = 107.21.211.20
[twilio-3]
type = identify
endpoint = twilio
match = 107.21.231.147
[twilio-4]
type = identify
endpoint = twilio
match = 54.236.81.101
[twilio-5]
type = identify
endpoint = twilio
match = 54.236.96.128
[twilio-6]
type = identify
endpoint = twilio
match = 54.236.97.29
[twilio-7]
type = identify
endpoint = twilio
match = 54.236.97.135
; south american gateways - not currently used but added for future use
[twilio-8]
type = identify
endpoint = twilio
match = 54.232.85.81
[twilio-9]
type = identify
endpoint = twilio
match = 54.232.85.82
[twilio-10]
type = identify
endpoint = twilio
match = 54.232.85.84
[twilio-11]
type = identify
endpoint = twilio
match = 54.232.85.85
; european gateways - not currently used but added for future use
[twilio-12]
type = identify
endpoint = twilio
match = 54.228.219.168
[twilio-13]
type = identify
endpoint = twilio
match = 54.228.233.229
[twilio-14]
type = identify
endpoint = twilio
match = 176.34.236.224
[twilio-15]
type = identify
endpoint = twilio
match = 176.34.236.247
; asian gateways - not currently used but added for future use
[twilio-16]
type = identify
endpoint = twilio
match = 46.137.219.1
[twilio-17]
type = identify
endpoint = twilio
match = 46.137.219.3
[twilio-18]
type = identify
endpoint = twilio
match = 46.137.219.35
[twilio-19]
type = identify
endpoint = twilio
match = 46.137.219.135
[twilio-20]
type = identify
endpoint = twilio
match = 54.249.244.21
[twilio-21]
type = identify
endpoint = twilio
match = 54.249.244.24
[twilio-22]
type = identify
endpoint = twilio
match = 54.249.244.27
[twilio-23]
type = identify
endpoint = twilio
match = 54.249.244.28
This works for me, so if you spot anything wrong with that I've missed, I'd greatly appreciate a message so I can update it for everyone else. :)