Chapter 7 Configuring and Debugging Fax Services

Debugging the Cisco ATA 186/188 Fax Services

Table 7-2 Debug Log Examples

Log event

Description

 

 

 

[ch] Enable encoder <pt>

Voice encoder type pt is enabled for the channel ch, where pt can be 0

 

for G.711µ-law, 4 for G.723.1, 8 for G.711A-law, and 18 for G.729.

 

For example, [0]Enable encoder 4 indicates that the Cisco ATA

 

transmitted G.723.1-encoded voice packets.

 

 

[ch] DPKT 1st:

The first voice packet that the Cisco ATA received was of RTP payload

<timestamp1>

type pt for the channel ch with timestamp of timestamp1, and the local

<timestamp2>, pt <pt>

decoding timestamp was set to timestamp2.

 

For example, [0]DPKT 1st: 1491513359 1491512639, pt 4 indicates

 

that the first RTP packet that the Cisco ATA received was

 

G.723.1-encoded for channel 0.

 

 

[ch] codec: <pt1> => <pt2>

Voice codec switchover occurred. The voice encoder type switched from

 

pt1 to pt2 for the channel ch.

 

For example,

[0]codec: 4 => 0 indicates that the local voice encoder

 

on the Cisco

ATA switched from G.723.1 to G.711µ-law.

 

 

[ch] Rx MPT PT=<NSEpt>

Channel ch received an NSE packet of event with payload type of NSEpt.

NSE pkt <event>

For event, c0XXXXXX indicates a CED tone event, and c1XXXXXX

 

indicates a phase reversal event.

 

For example, [0]Rx MPT PT=100 NSE pkt c0000000 indicates that the

 

Cisco ATA received a CED tone event NSE packet with payload type of

 

100.

 

 

 

[ch] Tx MPT PT=<pt> NSE

Channel ch transmitted an NSE packet of event with payload type of

pkt <event>

NSEpt. For event, c0XXXXXX indicates a CED tone event, and

 

c1XXXXXX indicates a phase reversal event.

 

For example, [0]Tx MPT PT=100 NSE pkt c0000000 indicates that the

 

ATA transmitted a CED tone event NSE packet with payload type of

 

100.

 

 

 

 

Debugging FAX Pass-through Mode

When the Cisco ATA is configured to use fax pass-through mode, the fax call session can be established with an arbitrary voice codec. Once the voice call has been established, fax machines can signal their presence by means of a CED tone or V.21 preamble flag, after which the gateways send NSE packets to initiate switchover.

Note For fax pass-through mode, check the Cisco ATA debug log to verify that it is acting as an originating gateway as well as a terminating gateway.

Terminating-Gateway Example

When the Cisco ATA is used as a terminating gateway for a fax session, make sure the following conditions are true:

The Cisco ATA transmits CED-tone-event NSE packets.

The encoder switchover to G.711 occurs during the NSE-packet transaction.

Cisco ATA 186 and Cisco ATA 188 Analog Telephone Adaptor Administrator’s Guide (H.323)

7-10

OL-4008-01

 

 

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Cisco Systems ATA 188 manual Log event Description, Terminating-Gateway Example

ATA 188 specifications

The Cisco Systems ATA 188 is a versatile Analog Telephone Adapter designed to facilitate the integration of traditional telephone systems with Voice over Internet Protocol (VoIP) networks. This device has been key in bridging the gap between legacy telephony and modern IP-based communication, allowing users to leverage their existing analog phones while enjoying the benefits of digital connectivity.

One of the main features of the ATA 188 is its ability to connect regular analog phones to a VoIP network, enabling users to make and receive calls over the internet. This significantly reduces calling costs, especially for long-distance and international calls. The ATA 188 supports two phone lines, allowing simultaneous voice calls. This dual-line capability makes it a suitable choice for small businesses or home offices that require multiple lines without the need for extensive infrastructure.

The device is equipped with various technologies that enhance its functionality. It supports the Session Initiation Protocol (SIP) and H.323, making it compatible with a wide range of VoIP service providers. Additionally, the ATA 188 features Quality of Service (QoS) settings, which prioritize voice traffic over the internet, ensuring clear voice quality without interruptions or delays. This is essential for maintaining a professional communication experience, especially in business environments.

Another characteristic of the ATA 188 is its user-friendly configuration interface. It allows users to easily set up and manage their devices through a web-based portal. The configuration process is straightforward, with options to adjust settings such as codec selection, call features including call waiting, and call forwarding functionalities.

Security is also a priority for the ATA 188, as it provides robust protocols to protect call data. The device supports Secure Real-time Transport Protocol (SRTP) and Transport Layer Security (TLS) to encrypt voice traffic and manage signaling securely. This ensures that sensitive conversations remain confidential.

Overall, the Cisco Systems ATA 188 is a reliable and efficient solution for users looking to transition from traditional telephony to VoIP. Its dual-line capacity, compatibility with multiple VoIP standards, user-friendly configuration, and built-in security features make it a valuable asset for both personal and professional communication solutions. In an ever-evolving telecommunications landscape, the ATA 188 remains a relevant and practical choice for integrating legacy telephony with modern internet-based services.