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ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Welcome to the Cisco Networking Professionals Ask the Expert conversation. This is an opportunity to discuss Cisco CallManager Faxes and Modems with Cisco expert David Goodwin. Dave Goodwin is a Technical Assistance Center (TAC) voice escalation engineer. Dave is involved in handling escalation issues and new product testing. He has been working with Cisco's voice product line for more than four years, with a focus on CallManager and associated applications. Remember to use the rating system to let David know if you have received an adequate response.

Dave might not be able to answer each question due to the volume expected during this event. Our moderators will post many of the unanswered questions in other discussion forums shortly after the event. This event lasts through January 16. Visit this forum often to view responses to your questions and the questions of other community members.

41 REPLIES
New Member

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

With respect to "golden bridge" documents, what

current software levels on IOS based gateways,

VG248, and ATA-18x's seem to provide the best

ability to provide fax and modem services?

It would be nice to know of a couple different

preferences as client environments vary.

--- Thanks ---

Cisco Employee

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi Calvin,

One key concept when considering gateways that will be used for fax and/or modem communication is the compatibility (in terms of capabilities and configuration) of the TWO gateways involved at the IP endpoints. For example, one fax machine will always be connected to some type of gateway's FXS port, and the other gateway could either be another gateway's FXS port (for an on-net fax) or more commonly, it would be another gateway's PRI, T1 CAS, analog FXO port, etc.

All the permutations of which gateway, which port type, which protocol (e.g. H.323/MGCP), which version, work with which other gateway with these same attributes, are too many to simply type out a list for you. However, here are some good rules of thumb that I always use as a starting point. Some of the version recommendations are based on ‘Golden Bridge’ and some are from my own and other’s experiences.

1. The Cisco Fax Relay codec can be used with IOS 17xx/26xx/36xx/37xx gateways (H.323/MGCP), VG248, 6608, 6624. CallManager needs to be aware of the codec for Fax Relay, so at this time only Cisco Fax Relay capable gateways are supported, no T.38 at the time of this writing (unless bypassing the CCM).

2. Modem relay is not supported in CCM at this time, so the only way it can work is through bypassing the CCM.

3. ATA18x gateways support fax passthrough and modem passthrough only at this time. Since many customers will use this gateway due to its small size and cost (or may add them later), it would be a good idea to disable fax relay on all other gateways in the network and insure they are set for ‘IOS-mode’ for NSE negotiation.

4. IOS for 17xx/26xx/36xx/36xx = 12.2(15)T8. To configure fax and modem passthrough for H.323, use:

voice service voip

fax protocol pass-through g711ulaw

modem passthrough nse codec g711ulaw

To configure fax and modem passthrough for MGCP, use:

no ccm-manager fax protocol cisco

mgcp modem passthrough voip mode nse

5. VG248 software = 1.2(1). To configure fax passthrough, set the Telephony Port Specific Parameters for each desired port for Fax Relay (disabled). Also set the Telephony Advanced Settings for Passthrough signaling to (IOS mode).

6. ATA18x software = 2.16.1.ms

7. 6608 load = D0040400006, 6624 load = A0020400005. To configure fax passthrough, go to each desired port, uncheck Fax Relay Enable, and set the NSE Type to IOS Gateways.

NOTE: #6 and #7 above will be automatically installed and used as the default firmware load when using Cisco CallManager 3.3(3) sr2 or later. They will work with any version of Cisco CallManager 3.3(x) or later, however, support for previous versions is not present (for the 6608/6624 gateways).

Hopefully this helps give you a good start that you can apply to any customer situation.

New Member

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Have a client (credit union) which still requires modems for some "FED" transacations and remote ATM's. Over 1 year ago we tried to use the vg248 as the device to relay the modem and fax calls to the associated devices. We worked with TAC, but finally abandoned the option and now have dedicated lines for the corporate site. (both dial in and out)

Speed issues, poor negoiations and drops were the norm. I do know they were using a special modem protocols for the bank transactions, but that is the only unique item.

The VG248 is working for analog phones, door keypads, and similar analog device. Are interested in working with the client again to remove dedicated analog lines and try to get workging again. Also have some ATA186's if recomended.

?? Is there more history and a proven track record with the "relay" capabilities. I often felt when speaking with TAC I sould not expect perfection with a FAX or modem relay. This is not to say my environment or my own capabilities we not the issue, but my experienc is that this is one area traditional PBX's do well at.

? looking for first steps using the post as a basic guide.

?? Would like to know if you have prefer ATA18x or vc248 for modems

??? Any issues with G3 33.6 Kbps FAX, only able to get 9600 with relay

vg248Version

-----------------------------------------

Software version : 1.2(1)

DSP firmware version : 3.6(20x)

Loader version : 1.0(1)

Cisco Employee

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi John,

Thanks for the detailed information. Firstly, I would recommend against using ATA186s for modem connections, as modems are completely unsupported on that platform; you should use VG248s.

Modem relay is not supported as a codec in Cisco CallManager, nor is it available on the VG248, so to use it, you would need to have two IOS gateways that support modem relay, and configure the dial-peers to bypass the CCM. So I assume this means you would be using modem passthrough.

Another considerations to think about are the network topology. Modems are very sensitive to jitter (changes in delay). So it’s extremely important that QoS with proper marking, treatment, strict priority, and call admission control, are appropriately implemented. A great place to start with that (minus the CAC portion) would be the QoS SRND which can be found at http://www.cisco.com/go/srnd

Finally, you haven’t what the other gateway at the other end of the IP network from the VG248 will be. Without knowing the details, it’s also obviously important to make sure that it’s optimally configured for modem passthrough to handle these calls.

Regarding 33.6kbps Fax calls, this is known as Super G3, and you can think of a call that has been negotiated (or tries to negotiate) as Super G3 as a modem call, because the fax machines actually use the same V.34 that 33.6kbps modems use. The Cisco fax relay codec will allow you to reach up to 9600 or 14400 depending upon the configuration of the originating and terminating gateways involved in the call. If you wish to transmit/receive faxes at higher speeds, you should follow the same guidelines for these machines as if they were modems.

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

I keep seeing references to Golden Bridge documents, what are these and where are they found?

Cisco Employee

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

As far as I am aware, Golden Bridge is a code name for an internal, long-term solution testing project. Cisco internal code names frequently tend to seep out into the public eye, so that's why you've heard about it.

I have sent a note to one of the coordinators of the project to find out if there are plans to externalize any of the resulting documents, or if this is already the case, and I will let you know what I find out.

New Member

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Cisco Employee

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Gary is the man!

Here is the link to all versions of "IP Communications Systems Test Releases" which corresponds to the Golden Bridge code name:

http://www.cisco.com/univercd/cc/td/doc/product/voice/ip_tele/gblink/index.htm

New Member

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

What is the Best way to setup a ATA 186 fax with MGCP and CallManager. Is this possible?

Thanks

Cisco Employee

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi Jason,

Cisco CallManager only supports MGCP gateways for which it has "profiles," or a layout of the possible slot and port types. SCCP (Skinny) is the signaling method of choice to use with an ATA186 to talk directly with CallManager. H.323 is also possible, but SCCP provides a much more feature-rich environment in this case.

An excellent guide for configuring the ATA186 using SCCP exists at:

http://www.cisco.com/univercd/cc/td/doc/product/voice/ata/ataadmn/sccp/index.htm

In particular, the sections "Configuring the Cisco ATA for SCCP" and "Adding the Cisco ATA to the Cisco CallManager" should assist you with the initial setup, and the section "Configuring and Debugging Fax Services" should help with your options for fax and modem passthrough.

By default, fax and modem passthrough should be allowed and is setup to use IOS style NSEs. I would recommend using version 2.16.1.ms as the best image right now for this purpose.

New Member

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hello Sir,

-is it possible to let Cisco ATA186s( insalled in Remote branches ) to talk using H323 Protocol( VoIP and Fax Traffic) to a MultIVOIP device MVP-410G ( from Multi Tech Systems ) ? is there any compatiblity issue between both devices ?

Note : the MutliVOIP is installed in the Headquarter and it is acting as a voice Gateway and a Gatekeeper at the same time ( Gk: in order to route calls between ATAs, Voice Gateway : in order to terminate and initiate calls with the ATAs at the remote Branches).

-i have a 7206 VXR series running the software :c7200-jo3s-mz.122-4.b5.bin ,

how could i check that the Gatekeeper feature is embedded with that software?

Note : once i do show running-config , i am getting in the display the following : gatekeeper

shutdown

is that enough to say that Gatekeeper feature is there?

Regards,

Ali

Cisco Employee

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi Ali,

Yes, seeing:

gatekeeper

 shutdown

in the configuration indicates that the IOS image running includes the GK feature.

Regarding the ATA186 using H.323 to talk with the 3rd party system, I am not familiar with it so I am not sure what it supports and what it does not. We are compatible with the ITU-T’s H.323 specification and its related standards (e.g. H.225.0 and H.245) and anything discovered which is not in line with the requirements of the specification should be considered a defect.

That being said, and assuming there are no H.323 or RAS signaling issues between the ATA186 and 3rd party gateway/gatekeeper, the ATA186 only supports fax passthrough at this time. That means that the other gateway must also support fax passthrough, and it should do this using the standard NSE methods. More information about configuring the ATA186 for fax options while using H.323 can be found here:

http://www.cisco.com/univercd/cc/td/doc/product/voice/ata/ataadmn/ata_h323/h3288apd.htm

In particular, the section called ConnectMode will contain useful information if you must change the NSE payload type to a value other than its default of 100.

New Member

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi Dave,

we are using VG248s (with 1.2.1) for a lot of analogue phone, some faxes and about 20 modems.

Fax and analogue phones are working, but the modems are not (properly).

We are using IOS-mode on VG248 and the above mentioned configuration on 1760-gateways.

We tried to find out which configuration is the optimum for modems and we failed. We have to full fill the following conditions: no changes on modems, make sure every connection attempt will be sucessfully and the minimum speed is about 20 kbit/s.

The tests in our office - we really ftp about 1 MB for three times - shown that we have to configure the modem-port to:

- passthrough = automatic

- fax-relay = disabled

We set all modem ports to that configuration and people, who are using modems for remote-administration (telnet and ftp) complain about it.

In some cases we have to use:

- passthrough = passthrough

- ECAN = enabled

- fax-relay = disabled

- input gain = -2

otherwise connections are not established.

Some connections seem to be unstable, when you transmit more than a few bytes and break after getting slower and slower.

The question is: Is there a configuration which full fills our needs? (no changes on modems, stable connection, transfer-rate about 20 kbit/s)

By the way, we never had trouble with these modems using a traditional PBX.

Thanks in advance,

Axel

Cisco Employee

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi Axel,

Some suggestions and comments:

- fax-relay = disabled is a good idea, but I don’t think it will relate to this issue

- ECAN = If anything, I would expect the enabled setting to actually be more negative than positive. Modem calls should have the ECAN disabled. When the VG248 detects modem tones and goes into modem passthrough mode, it disables the ECAN.

- Input gain –2 will help to resolve any issues where the signal level coming in from the modem to the VG248 is too hot. Changing this setting may be helpful in some environments with some modems.

I think what would also be very enlightening to analyze this issue is the configuration of the other gateway involved in the fax call: the one closest to the other modem. Knowing the IOS version and configuration would be useful; depending on how it’s set up, there are a number of things that should be configured on the IOS side in order to insure proper modem passthrough operation.

Finally, you haven’t mentioned the network topology that covers the entities between the VG248 and IOS gateway. It’s especially important for fax and modem passthrough networks to have QoS properly configured to insure no extra delay or jitter takes place between the two IP endpoints of the call. Each router and switch between these two endpoints should be configured to set the COS and DSCP fields properly, and QoS should be enabled where needed to prioritize the voice (fax/modem too!) packets over any other packets, especially if there are any slower links involved in the network. You can find the QoS design guide at:

http://www.cisco.com/go/srnd

New Member

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi Dave,

we are using two 1760 with IOS 12.2(11)YU and 12.2(15)T.

The Advanced Settings on the VG248 are:

Allow last good configuration (enabled) |

| SRST policy (disabled) |

| SRST provider () |

| Call preservation (enabled: no timeout) |

| Media receive timeout (disabled) |

| Busy out off hook ports (disabled) |

| DTMF tone duration (default: 100ms) |

| Echo cancelling policy (default: use SLIC) |

| Hook flash timer () |

| Hook flash reject period (none) |

| Passthrough signaling (IOS mode) |

| Fax relay payload size (default: 20) |

| Fax relay maximum speed (default: 14400 bps) |

| Fax relay playout delay (default: 300)

The configuration on IOS-Gateways are:

dial-peer voice 45721 voip

preference 1

destination-pattern 4572...

progress_ind setup enable 3

translate-outgoing calling 1

translate-outgoing called 2

modem passthrough nse codec g711ulaw

session target ipv4:

codec g711ulaw

ip qos dscp cs5 media

no vad

!

Both gateway are in the same subnet, same vlan are connected with 100full to one of two 6509 Switches and a 4 GBit/s trunk between those. We have no QoS in our LAN. We have no trouble with IP-phones! Do you think there is a need for QoS? Normally max. jitter on 7960 is about 3.

Do you need more information?

Thanks in advance,

Axel

Cisco Employee

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi Axel,

Based on the information you have provided, I would say that your configuration is sound, as well as the network topology, even without QoS on the switches, as I doubt this would be required on a 4Gbps trunk.

I would suggest you work with Cisco TAC on getting this resolved. If they are unable to find any existing software defects relating to modem passthrough in the versions you are running (it's quite possible there are from the versions you told me), then they can open a new defect, and providing them with sniffer traces which show the entire failed or unacceptable modem call from start to finish may assist them in this endeavor. Good luck!

New Member

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Is there a list of approved fax, multi-purpose,

fax-modem, and modem brands/models available from

Cisco showing compatability with AVVID?

In troubleshooting fax/modem problems, there seems

to be brands and makes which work fairly easily,

and then there are those which make implementations

quite difficult.

Or if there is no official approved list, is there an

unofficial list that talks to non-compatability? (grin)

--- Thanks ---

Cisco Employee

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi Calvin,

As far as I am aware, there is unfortunately no actual list of supported brands/models of fax machines and modems. As I'm sure you are aware, the market is flooded with thousands of different makes and models of each, some of them still being made and some not.

What I can tell you from experience is that when we experience issues communicating with a fax machine or modem, we do our utmost to troubleshoot the communication problem all the way to root cause. If it's our problem, we fix it. If it's their problem, we try to compel them to fix it. If they are not around anymore or are not willing to fix it, we do our best to come up with a reasonable solution for the customer. I know that's not the answer you were looking for, but hopefully it helps.

New Member

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi Dave, Looking at the previous conversations & my own experiences with modems particularly, there seems no foolproof/supported hardware available from Cisco that fits in with the AVVID model. Are there any moves within Cisco to address this as I would have thought that support for these analogue items would be a necessity for a good migration from old to new technologies?

Thanks

Paul

Cisco Employee

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi Paul,

Cisco does do extensive fax and modem testing against our products which support passthrough and relay technologies, and this testing is done with a good variety of different vendors and models, as well as with test equipment capable of simulating different types of equipment.

However, no such list is available at this time.

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hello Dave. I wanted to get your thoughts on feasability before I trucked 500 miles to a remote site.

Remote site= IP Phone--->VPN3002--->PIX--->2651XM--T1

Central Site= T1-->3640(1)---VPN3005-->LAN--3640(2)-->PRI--PSTN

CCM3.3 at central site

I want to put an ATA18x behind the VPN3002 at the remote site with a fax machine plugged into it. At first glance it seems like it would work. AM I missing something that would make Analog FAX over VPN not feasable? I am already aware of the lack of QoS over the Internet but I am already runing the VoIP over VPN w/o any problems due to a good deal of planning beforehand. Thanks in advance!!

Cisco Employee

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi Travis,

Yes you should be able to get it to work. Since no guarantees are available over the Internet without a special SLA from the provider(s), no guarantees can be made for consistent and successful fax performance, just like none can be made for a regular voice call. That being said, I have done all of the above with no problem, with much less bandwidth than T1.

In any case, it would be a very good idea to insure that IPSec packets between the 3640(1) and 2651XM are marked with DSCP ef, and that you are doing LLQ on that T1 link as well, to insure these IPSec packets are prioritized over any other traffic, if it exists.

I would also recommend you read the SRND for Voice and Video enabled IPSec VPN (V3PN) which can also be found on the SRND page at http://www.cisco.com/go/srnd

New Member

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

I have a problem using T37 Store and Forward fax. I have an AS 5300 running IOS 12.2 (have tried 12.3) and have been using T37 fax for about 2 years. I have never encountered any problems until recently.

95% of off-ramp faxing works fine. The remaining 5% of faxing doesn't work because of the failure of DIS/DCS handshake. The call is released without any transmission of the data. See trace:

WORKING FAX

Jan 7 11:13:02.150: 0:D (214) 73430150 fr-entered (10ms)

Jan 7 11:13:02.262: 0:D (214) 73430260 fr-pkt-loss 2

Jan 7 11:13:08.753: 0:D (214) 73436740 fr-msg-det NSF

Jan 7 11:13:09.314: 0:D (214) 73437300 fr-msg-det CSI

Jan 7 11:13:10.035: 0:D (214) 73438020 fr-msg-det DIS

Jan 7 11:13:10.784: 0:D (214) 73438770 fr-msg-tx TSI

Jan 7 11:13:12.058: 0:D (214) 73440040 fr-msg-tx DCS

Jan 7 11:13:18.845: 0:D (214) 73446820 fr-msg-det CFR

Jan 7 11:13:27.411: 0:D (214) 73455370 fr-msg-tx EOP

Jan 7 11:13:31.446: 0:D (214) 73459400 fr-msg-det MCF

Jan 7 11:13:31.899: 0:D (214) 73459850 fr-msg-tx DCN

NOT WORKING

Jan 7 11:07:26.691: 0:D (207) 73890580 fr-entered (10ms)

Jan 7 11:07:26.799: 0:D (207) 73890690 fr-pkt-l

Jan 7 11:07:33.710: 0:D (207) 73897590 fr-msg-det NSF

Jan 7 11:07:34.784: 0:D (207) 73898660 fr-msg-det CSI

Jan 7 11:07:35.473: 0:D (207) 73899350 fr-msg-det DIS

Jan 7 11:07:36.014: 0:D (207) 73899890 fr-msg-tx TSI

Jan 7 11:07:37.288: 0:D (207) 73901160 fr-msg-tx DCS

Jan 7 11:07:42.605: 0:D (207) 73906470 fr-msg-det NSF

Jan 7 11:07:43.678: 0:D (207) 73907540 fr-msg-det CSI

Jan 7 11:07:44.368: 0:D (207) 73908230 fr-msg-det DIS

Jan 7 11:07:44.900: 0:D (207) 73908760 fr-msg-tx TSI

Jan 7 11:07:46.171: 0:D (207) 73910030 fr-msg-tx DCS

Jan 7 11:07:51.491: 0:D (207) 73915340 fr-msg-det NSF

Jan 7 11:07:52.561: 0:D (207) 73916410 fr-msg-det CSI

Jan 7 11:07:53.254: 0:D (207) 73917100 fr-msg-det DIS

Jan 7 11:07:53.795: 0:D (207) 73917640 fr-msg-tx TSI

Jan 7 11:07:55.065: 0:D (207) 73918910 fr-msg-tx DCS

Jan 7 11:08:00.386: 0:D (207) 73924220 fr-msg-det NSF

Jan 7 11:08:01.447: 0:D (207) 73925280 fr-msg-det CSI

Jan 7 11:08:02.149: 0:D (207) 73925980 fr-msg-det DIS

Jan 7 11:08:02.677: 0:D (207) 73926510 fr-msg-tx DCN

Jan 7 11:08:04.773: %ISDN-6-DISCONNECT: Interface Serial0:30 disconnected from

Jan 7 11:08:04.781: %LAPP_OFF-6-LAPP_OFF_CAUSE_ABNORMAL: Call aborted

Cisco Employee

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi Vik,

Is there a fax number where the problem can be consistently reproduced?

If so, can you explain the full topology between the two fax endpoints? This is important, because from the T30 messaging seen in the failed call is almost always due to a timing issue on the network. So it would be useful to know if there are any IP clouds or international hops, etc. between the AS5300 and the called fax machine.

I would recommend that to solve this issue you should raise a Cisco TAC case at http://www.cisco.com/cgi-bin/front.x/case_tools/caseOpen.pl

What will be important to get to the bottom of the problem is one or more numbers where the problem is reproducible. We can then attempt to reproduce the problem from the lab with both an AS5300 off-ramp as well as a standard fax machine, and we have the ability to insert a fax analysis tool between the machines to find out what is going wrong.

Gold

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Dave,

Is T.38 fax relay support on the roadmap for CallManager? It's one of those small things that sometimes forces us to configure gateways as H.323 rather than MGCP. For instance, the XMediusFAX fax server product (which also happens to interoperate with Unity's fax support) requires T.38.

While we're on the subject, is modem relay on the roadmap?

Blue

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Dave,

In an earlier post you stated the commands below were for H.323 gateways. I am little confused becuase some of the commands are mgcp related. I typically use these commands in an MGCP environment and it has significantly helped with faxing:

4. IOS for 17xx/26xx/36xx/36xx = 12.2(15)T8. To configure fax and modem passthrough for H.323, use:

voice service voip

fax protocol pass-through g711ulaw

modem passthrough nse codec g711ulaw

To configure fax and modem passthrough for MGCP, use:

no ccm-manager fax protocol cisco

mgcp modem passthrough voip mode nse

Cisco Employee

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi ,

You are correct, some of those commands are in fact MGCP related. Maybe I should have split up that suggestion into two different items, but if you look closely, you can see in there I have:

H.323:

voice service voip

 fax protocol...

 modem passthrough...

To configure fax and modem passthrough for MGCP, use:

no ccm-manager...

mgcp modem...

So in #4 I was actually pointing out H.323 related commands, and then MGCP related commands. Hope that clears it up.

Cisco Employee

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi Jason,

Sorry it took me so long to respond to your question; I wanted to get my facts straight before answering.

Yes, T.38 fax relay support is on the roadmap for Cisco CallManager. It has not yet been committed, but is currently slated to be released in a future version later this year (not CCM 4.0). When it is released, there *may* be some restrictions on its use initially, e.g. MGCP vs. H.323, fast start vs. slow start. None of this is set in stone yet, and I cannot provide any more concrete dates yet, so you'll need to stay tuned to this.

As far as I'm aware, modem relay is not yet on the roadmap for Cisco CallManager support.

For both T.38 and modem relay, you can certainly still utilize both features with Cisco gateways that support this protocol, however as you mentioned, you must continue to bypass the CallManager (route calls around it) until these relay protocols are supported in CCM.

New Member

Re: ASK THE EXPERT- CALLMANAGER FAXES AND MODEMS

Hi all,

I have Cisco 3640 attached to a modem bank. The objective is to

connect from Windows platform clinet to this modem and establish a PPP

connection to the network.

I have configured the routes as below:-

Current configuration:

!

version 11.3

service timestamps debug uptime

service timestamps log uptime

service password-encryption

!

aaa new-model

aaa authentication ppp default local

!

interface Serial2/0

physical-layer async

description **dial-ppp port Tel #

ip address 10.1.1.7 255.255.255.252

encapsulation ppp

ip tcp header-compression passive

async mode interactive

no snmp trap link-status

peer default ip address 10.1.1.6

no cdp enable

ppp authentication chap

The problem is when I use dial up on Win2K with a after dial terminal,

it got:

username challage, and after I entered the correct username and

password, I got the router> prompt and I typed PPP at the prompt and

pressed done.

After that I will get Window pop out of veryfing username and password

and disconnect.

Please help, and many thanks in advance

rgds,

Zulfikri

1004
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