Archive for the ‘Analog’ Category

ATA 186 auto registration

Posted: July 10, 2006 by sankar in Analog, ATA186

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.

MGCP & H323 IOS gateway and T38 faxing

Posted: May 28, 2006 by sankar in Analog, Fax

MGCP gateways and T38 

1. mgcp fax t38 ls_redundancy 0  OR

    mgcp fax t38 hs_redundancy 0

ls_redundancy set to 0 disables mgcp from sending redundant packets. The value can be set from  0  – 5 or 7 packets

hs_redundancy set to 0 disables mgcp from sending redundant packets for high speed fax m/c v.17, v27, v29 T.4 or T.6 fax machine. Default is 0, Can be configured up to 2 or 3.  0 disables redundancy.

Optional commands:

mgcp fax t38 gateway force  – This command forcest38 fax relay using NSE's eve if T38 and NSE's cannot be negotiated by the MGCP call agent at call setup time

mgcp fax t38 inhibit – Disables MGCP T38 fax relay.

mgcp tse payload <value>  – TSE is for Telephony signalling event. This command specifies payload value during fax and modem passthrough. Default is 100.

mgcp fax rate <rate>|voice  (Default rate is 7200 bps)

H323 gateways and T38

dial-peer voice 1 voip

fax rate voice

fax protocol t38 ls_redundancy 0

options available are : 

force – forces use of NSE;s to switch to T38 fax relay

fallback pass-through  g711ulaw | g711alaw – A fallback mode if T38 could not be negotiated.

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)

Posted: May 28, 2006 by sankar in Analog, ATA186, Fax

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

Posted: May 28, 2006 by cciestudy in Analog, ATA186, Fax, QOS

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

Posted: May 27, 2006 by sankar in Analog, ATA186, Fax

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.

Audiomode – 0x00150015

0000 0000 0001 0101 (last 4 hex digits represents phone 1)

Bit 0 – 1 enables VAD

Bit 2 – 1 enables fax CED tone detection

Connect mode : 0x90000400

1001 0000 0000 0000 0000 0100 0000 0000

Bits 12 – 8 represent NSE payload type offset. Default NSE payload type is 100 for ATA which means the offset is set to 4 (00100). IOS H323/SIP gateways use NSE payload type 100. Most MGCP gateways using 6608 uses NSE payload type 101. So set the offset to 5 (00101) if setting up fax between ATA and 6608 (older versions)

Bits 13 – default 0 – represents fax pass through codec. 0 means g711ulaw, 1 means g711alaw.

To use fax in countries other than US, set

Connect mode : 0x90002400
**** key things to remember about interoperability of various AVVID fax components******

If a VG248, Cisco IOS router, MGCP gateway and ATA 186 is involved in faxing. Then set the NSE payload type to 100 (IOS Mode) in all devices. In VG248 set to IOS mode. In router by default NSE payload type is 100 (for modem passthrough). In MGCP IOS gateway (need to check). In 6608 set the mode to IOS mode. In ATA 186, default NSE payload type is 96 + offset of 4 = 100.