ATA 186 auto registration

To disable auto registration for any of the port set Sid 0 or Sid1 to 0 or empty. This will disable the port and not attempt a registration with CM. If you want to manually add the port in CM, put Sid0 or Sid1 as the mac-address of the appropriate port.

ATA – Technology Prefix

To have the ATA prepend Tech prefix for outgoing calls, do the following

1. AutMethod = 0x00000004

2. PWD0 = 1#

ATA and Voice VLAN

New ATA’s support trunking and understand Voice VLAN via CDP. So you can configure the ports like IP Phone ports

MGCP IOS gateway and ATA 186 in H323 mode – Fax Passthrough configuration

1. Configure MGCP gateway as usual (with FXS ports).

2. Give the following commands

     no ccm-manager fax protocol   — disables cisco fax relay

     mgcp modem passthrough voip mode nse  — enables modem passthrough

     mgcp modem passthrough voip codec g711ulaw

MGCP default NSE payload types

Output of "Sh mgcp"

MGCP media bind :DISABLED
MGCP Upspeed payload type for G711ulaw: 0,  G711alaw: 8 (You may opt to match this up with ATA NSE payload type)
MGCP Dynamic payload type for G.726-16K codec
MGCP Dynamic payload type for G.726-24K codec

3. Optionally you may want to disable T38 fax relay for MGCP (which is enabled by default)

mgcp fax t38 inhibit. (Useful if you want to just have passthrough enabled, and disable t38 fax on the gateway)

ATA 186 Fax modes (H323)

Fax pass through – Set audio mode to 0x00150015

Fax mode – (Use direct g711 only, it doesn't do any codec upspeed.) – Set audiomode to 0x00120012

12 – corresponds to 0001 0010

bit 1 – set to 1 for g711 only

bit 2 – set to 0 to disable CED

DSCP settings for H323 and MGCP gateways

The setting below applies to packets generated by teh router itself.

For H323 gateways

Default for signaling is af31 (26). Need to change this to cs3 (24).

dial-peer voice 1500 voip
ip qos dscp cs3 signaling 

For MGCP gateways

mgcp ip qos dscp cs3 signaling

IOS gateways – faxing – three steps

To enable fax passthrough in a H323 IOS gateway: (This can be given under a dial peer or globally under voice service voip mode)

Global mode:

1.  modem passthrough nse [payload-type number] codec {g711ulaw|g711alaw} [redundancy] [maximum-sessions <value>]

* Payload-type default : 100 for IOS gateways (Set this to same for all other gateways)

* Codec should be g711ulaw for fax sent over a t1 trunk or g711alaw for fax sent over a e1 trunk

* redundancy – enables fax redundancy. Set this parameter to be same at both ends

* max sessions – defines how many fax calls can occur simultaneously. Default is 16. Valid values 1 – 26.

2. Disable Fax relay – Fax relay is enabled by default and takes precedence over Passthrough.

fax rate disable

3. If you gave the modem passthrough setting under voice service voip mode, then you need to give the following command in dial-peer mode.

dial-peer voice 1 voip

modem passthrough system

Dial-peer mode: (2 steps)

 If you choose not to apply the modem passthrough settings in global mode, dial-peer voice 1 voip

fax rate disable

modem passthrough nse codec g711ulaw

To enable Fax passthrough in a Cisco IOS MGCP gateway

no ccm-manager fax protocol cisco

mgcp modem passthrough voip mode nse

mgcp modem passthrough voip codec g711ulaw|g711alaw.