UDPTL Port range

Asterisk Asterisk Fax
1

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.

2

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

3

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

4

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

5

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

6

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

1 Like
7

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