I believe they use Call Manager.
Here's part of the show run:
voice-port 1/0/0
cptone AR
timeouts interdigit 2
connection plar 2355
station-id name Pater_PHONE
caller-id enable
!
voice-port 1/0/1
cptone AR
timeouts interdigit 4
timeouts ringing infinity
timing hookflash-in 900 400
station-id name Suc_8_Fax
caller-id enable
!
voice-port 1/0/2
cptone AR
timeouts interdigit 4
timeouts ringing infinity
timing hookflash-in 900 400
station-id name Suc_8_Cast
caller-id enable
!
voice-port 1/0/3
cptone AR
timeouts interdigit 4
timeouts ringing infinity
timing hookflash-in 900 400
station-id name Suc_8_ATM
caller-id enable
!
voice-port 1/0/4
cptone AR
timeouts interdigit 4
timeouts ringing infinity
timing hookflash-in 900 400
station-id name Suc_8_Denver
caller-id enable
!
voice-port 1/0/5
cptone AR
timeouts interdigit 4
timeouts ringing infinity
timing hookflash-in 900 400
station-id name Suc_8_Denver
caller-id enable
!
voice-port 1/0/6
cptone AR
timeouts interdigit 4
timeouts ringing infinity
timing hookflash-in 900 400
station-id name Suc_8_Denver
caller-id enable
!
voice-port 1/0/7
cptone AR
timeouts interdigit 4
timeouts ringing infinity
timing hookflash-in 900 400
station-id name Suc_8_Denver
caller-id enable
!
voice-port 1/0/8
trunk-group PSTN
supervisory disconnect dualtone mid-call
supervisory custom-cptone country-ar
cptone AR
timeouts interdigit 4
timeouts call-disconnect 2
shutdown
impedance complex2
description ## LIBRE ##
!
voice-port 1/0/9
trunk-group PSTN
supervisory disconnect dualtone mid-call
supervisory custom-cptone country-ar
cptone AR
timeouts interdigit 4
timeouts call-disconnect 2
shutdown
impedance complex2
description ## LIBRE #
!
voice-port 1/0/10
trunk-group PSTN
supervisory disconnect dualtone mid-call
supervisory custom-cptone country-ar
cptone AR
timeouts interdigit 4
timeouts call-disconnect 2
shutdown
impedance complex2
description ## LIBRE ##
!
voice-port 1/0/11
trunk-group PSTN
supervisory disconnect dualtone mid-call
supervisory custom-cptone country-ar
cptone AR
timeouts interdigit 4
timeouts call-disconnect 2
shutdown
impedance complex2
description ## LINEA3 ##
!
voice-port 1/0/12
trunk-group PSTN
supervisory disconnect dualtone mid-call
supervisory custom-cptone country-ar
cptone AR
timeouts interdigit 4
timeouts call-disconnect 2
impedance complex2
description ## 1348 ##
!
voice-port 1/0/13
trunk-group PSTN
supervisory disconnect dualtone mid-call
supervisory custom-cptone country-ar
cptone AR
timeouts interdigit 4
timeouts call-disconnect 2
impedance complex2
description ## 1074 ##
!
!
!
!
ccm-manager fallback-mgcp
ccm-manager mgcp
ccm-manager music-on-hold
ccm-manager sccp local Loopback2
!
no mgcp package-capability res-package
no mgcp package-capability fxr-package
no mgcp timer receive-rtcp
!
mgcp profile default
!
sccp local Loopback2
sccp ccm 172.25.29.179 identifier 2 version 7.0
sccp ccm 172.31.26.37 identifier 1 version 7.0
sccp
!
sccp ccm group 1
associate ccm 1 priority 1
associate ccm 2 priority 2
associate profile 1 register XCODE_Suc8
associate profile 3 register MTP_Suc8
associate profile 2 register CFB_Suc8
switchback method graceful
!
dspfarm profile 1 transcode
codec pass-through
codec g729r8
codec g729abr8
codec g729ar8
codec g711alaw
codec g711ulaw
maximum sessions 5
associate application SCCP
!
dspfarm profile 2 conference
codec g729br8
codec g729r8
codec g729abr8
codec g729ar8
codec g711alaw
codec g711ulaw
maximum sessions 1
associate application SCCP
!
dspfarm profile 3 mtp
codec pass-through
codec g711ulaw
maximum sessions software 100
associate application SCCP
!
dial-peer cor custom
name PT_Emergencia
name PT_Servicios
name PT_0800
name PT_Locales
name PT_Celulares
name PT_DDN
name PT_DDI
!
!
dial-peer cor list dial-peer
!
dial-peer cor list CSS-Emergencias
member PT_Emergencia
member PT_Servicios
member PT_0800
!
dial-peer cor list CSS-Locales
member PT_Emergencia
member PT_Servicios
member PT_0800
member PT_Locales
!
dial-peer cor list CSS-Celulares
member PT_Emergencia
member PT_Servicios
member PT_0800
member PT_Locales
member PT_Celulares
!
dial-peer cor list CSS-DDN
member PT_Emergencia
member PT_Servicios
member PT_0800
member PT_Locales
member PT_Celulares
member PT_DDN
!
dial-peer cor list CSS-Loc-DDN
member PT_Emergencia
member PT_Servicios
member PT_0800
member PT_Locales
member PT_DDN
!
dial-peer cor list CSS
!
dial-peer cor list CSS-DDI
member PT_Emergencia
member PT_Servicios
member PT_0800
member PT_Locales
member PT_Celulares
member PT_DDN
member PT_DDI
!
!
dial-peer voice 1 voip
description ## Ruta internos 4 digitos - CUCM Activo ##
preference 1
destination-pattern [*1-9]...
session target ipv4:172.31.26.37
voice-class codec 1
voice-class h323 1
dtmf-relay h245-signal h245-alphanumeric
fax-relay ecm disable
fax rate 7200
no vad
!
dial-peer voice 2 voip
description ## Ruta internos 4 digitos - CUCM Backup ##
preference 2
shutdown
destination-pattern [*1-9]...
session target ipv4:172.31.86.14
voice-class codec 1
voice-class h323 1
dtmf-relay h245-signal h245-alphanumeric
fax-relay ecm disable
fax rate 7200
no vad
!
dial-peer voice 100 voip
description ## Ruta Preatendedor WAN ##
service macro
incoming called-number *100
codec g711ulaw
!
dial-peer voice 101 pots
trunkgroup PSTN
corlist outgoing CSS-Locales
description Locales
destination-pattern 0[3-7].....
!
dial-peer voice 102 pots
trunkgroup PSTN
corlist outgoing CSS-Celulares
description Celulares 8 Digitos
destination-pattern 015......
prefix 15
!
dial-peer voice 103 pots
trunkgroup PSTN
corlist outgoing CSS-DDN
description Larga Distancia Nacional
destination-pattern 00[1-3].........
forward-digits 11
!
dial-peer voice 104 pots
trunkgroup PSTN
corlist outgoing CSS-DDI
description DDI
destination-pattern 00T
prefix 00
!
dial-peer voice 105 pots
trunkgroup PSTN
corlist outgoing CSS-Locales
description 0800
destination-pattern 008T
prefix 08
!
dial-peer voice 106 pots
trunkgroup PSTN
corlist outgoing CSS-Emergencias
description Servicios
destination-pattern 01[^5].
forward-digits 3
!
dial-peer voice 107 pots
trunkgroup PSTN
corlist outgoing CSS-Emergencias
description Servicios
destination-pattern 1[^5].
forward-digits 3
!
dial-peer voice 108 pots
trunkgroup PSTN
corlist outgoing CSS-Emergencias
description 911
destination-pattern 0911
forward-digits 3
!
dial-peer voice 109 pots
trunkgroup PSTN
corlist outgoing CSS-Emergencias
description 911
destination-pattern 911
forward-digits 3
!
dial-peer voice 110 pots
trunkgroup PSTN
description Larga Distancia Nacional Celulares
destination-pattern 00[1-3].15........
forward-digits 13
!
dial-peer voice 111 pots
trunkgroup PSTN
description Celulares 6 digitos
destination-pattern 00[1-3]...15......
forward-digits 13
!
dial-peer voice 112 pots
trunkgroup PSTN
description Celulares 7 digitos
destination-pattern 00[1-3]..15.......
forward-digits 13
!
dial-peer voice 200 pots
destination-pattern 18799999
port 1/0/0
!
dial-peer voice 201 pots
service stcapp
port 1/0/1
!
dial-peer voice 202 pots
service stcapp
port 1/0/2
!
dial-peer voice 203 pots
service stcapp
port 1/0/3
!
dial-peer voice 204 pots
service stcapp
port 1/0/4
!
dial-peer voice 205 pots
service stcapp
port 1/0/5
!
dial-peer voice 206 pots
service stcapp
port 1/0/6
!
dial-peer voice 207 pots
service stcapp
port 1/0/7
!
dial-peer voice 208 pots
service macro
shutdown
incoming called-number .
port 1/0/8
!
dial-peer voice 209 pots
service macro
shutdown
incoming called-number .
port 1/0/9
!
dial-peer voice 210 pots
service macro
shutdown
incoming called-number .
port 1/0/10
!
dial-peer voice 211 pots
service macro
incoming called-number .
port 1/0/11
!
dial-peer voice 212 pots
service macro
incoming called-number .
port 1/0/12
!
dial-peer voice 213 pots
service macro
incoming called-number .
port 1/0/13
!
dial-peer voice 23551 voip
description ## Ruta HotLine - CUCM Activo ##
preference 1
destination-pattern 2355
session target ipv4:172.31.26.37
voice-class codec 1
voice-class h323 1
dtmf-relay h245-signal h245-alphanumeric
fax-relay ecm disable
fax rate 7200
no vad
!
dial-peer voice 23552 pots
trunkgroup PSTN
description ## Pater Phone en modo SRST ##
translation-profile outgoing HOTLINE
preference 5
destination-pattern 2355
!
!
!
!
gatekeeper
shutdown
!
!
call-manager-fallback
secondary-dialtone 0
max-conferences 3 gain -6
transfer-system full-consult
ip source-address 172.25.29.179 port 2000
max-ephones 100
max-dn 96 dual-line
