UDPTL Port range

Hello Everyone,

My customer got a requirement for T38-UDP ports range needs to be in between 10000 and 20000 range.
On Asterisk, the default UDPTL port range was UDP ports 4000-4999. I have modified this Port range through Asterisk’s udptl.conf file.
However, Asterisk still use the 4000 range for T38-UDP packets.
Is there any other configuration change is requires to take new port range effective? Please confirm.

Have you confirmed that the port settings took effect using “udptl show config”? If so what does the SDP look like?

I did not check before. It looks like, the port range is still the same:
UDPTL Global options

udptlstart: 4000
udptlend: 4999
udptlfecentries: 0
udptlfecspan: 0
use_even_ports: No
udptlchecksums: Yes

Did you restart or reload Asterisk after the change? What is the contents of the config file?

yes, I did service restart and then core reload. Still the port range did not change. Please find the snippet from my udptl.conf file:

; DEFAULTS:
;
; UDPTL start and UDPTL end configure start and end addresses
;
udptlstart=10000
udptlend=19999
;
; Whether to enable or disable UDP checksums on UDPTL traffic
;
; udptlchecksums=no
;
; The number of error correction entries in a UDPTL packet
;
; udptlfecentries = 3
;
; The span over which parity is calculated for FEC in a UDPTL packet
;
; udptlfecspan = 3
;
; Some VoIP providers will only accept an offer with an even-numbered
; UDPTL port. Set this option so that Asterisk will only attempt to use
; even-numbered ports when negotiating T.38. Default is no.
;
; use_even_ports = no

[general]
#include udptl_custom.conf

You do not have them in the general section, so they would not apply.

1 Like

Many Thanks Joshua! Applied it in custom file and got it working now.