ANM (Answer Message)

An Answer Message, commonly known as ANM, is a message sent by a device to indicate that it has received and is ready to accept an incoming call from another device. ANM is an important signal that facilitates call setup and connection between two devices in a communication network. In this article, we will explore the various aspects of ANM and its role in establishing successful voice and data calls.

ANM is one of the messages defined in the Signaling System 7 (SS7) protocol used in Public Switched Telephone Networks (PSTN) and Integrated Services Digital Networks (ISDNs). SS7 is a set of signaling protocols used for call setup and management in telecommunication networks. ANM is sent by the called party's exchange or network node to the calling party's exchange or network node in response to an incoming call request.

ANM carries important information that enables the calling party's exchange to connect the call to the appropriate channel and route it to the called party's device. ANM is sent after the called party's device has completed a range of activities, including ringing the phone, waiting for the called party to answer, and establishing the necessary signaling and bearer channels for voice or data transmission.

ANM is a positive acknowledgment message that indicates to the calling party's device that the called party's device is ready to accept the call. ANM signals the successful completion of call setup activities and prepares the devices for voice or data transmission. ANM is a crucial component in establishing a successful call connection and ensuring high-quality voice and data transmission.

ANM contains various fields that convey important information about the call setup status and the capabilities of the called party's device. The following are some of the important fields in ANM:

• Called party number: This field contains the phone number or network address of the called party's device. This field is used by the calling party's device to route the call to the appropriate channel and exchange.
• Call reference number: This field contains a unique identifier assigned to the call by the calling party's device. This identifier is used by both parties' devices to track the call's progress and status.
• Call setup status: This field indicates the status of the call setup process. ANM carries a range of status codes that convey information about the success or failure of call setup activities.
• Called party capabilities: This field contains information about the capabilities of the called party's device. This information includes the supported audio codecs, data transmission rates, and signaling protocols.

ANM is a critical component of the call setup process in telecommunication networks. ANM enables the calling party's device to determine whether the called party's device is ready to accept the call and establish the necessary channels for voice or data transmission. ANM also ensures that the devices are synchronized and configured correctly to enable high-quality voice and data transmission.

In addition to ANM, telecommunication networks use a range of other signaling messages and protocols to establish and manage voice and data calls. These messages include the Initial Address Message (IAM), Call Proceeding (CPD), and Connect (CON) messages. IAM is used by the calling party's device to initiate a call and provide the called party's phone number or network address. CPD is sent by the called party's device to indicate that it has received the IAM and is processing the call setup request. CON is sent by the called party's device to indicate that it has completed the call setup process and is ready to transmit voice or data.

In conclusion, ANM is a crucial signaling message used in telecommunication networks to establish and manage voice and data calls. ANM enables the calling party's device to determine whether the called party's device is ready to accept the call and establish the necessary channels for voice or data transmission. ANM contains important information that facilitates call setup activities and ensures high-quality voice and data transmission. ANM is just one of many signaling messages used in telecommunication networks, and it works in conjunction with other messages such as IAM, CPD, and CON to establish and manage voice and data calls.

ANM is a fundamental component of the call setup process, and it plays a critical role in ensuring that calls are successfully connected and transmitted. Without ANM, the calling party's device would not be able to determine whether the called party's device is ready to accept the call, and the call setup process would fail.