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Answer-seizure ratio

Answer-seizure ratio definition

The answer-seizure ratio (ASR) is a key performance metric used in telecommunication networks to evaluate the efficiency of a telephony system. The ratio is calculated by dividing the number of successfully answered calls by the total number of calls attempted (seized), typically presented as a percentage. ASR is a standard metric used worldwide, however, the benchmarks differ between networks and regions. Generally, an ASR of 40-50% is considered acceptable in the industry.

See also: call detail record

How answer-seizure ratio is calculated

Formula: ASR = (number of successfully answered queries) / (total number of queries)

When a call is initiated, it is “seized” by the network and an attempt is made to establish the connection. If the call is answered, it counts towards the numerator of the ASR ratio. If the call fails to connect, is dropped, or goes unanswered, it does not contribute to the numerator, but still contributes to the denominator (total calls attempted). Hence, the ASR provides insight into the network's ability to effectively connect calls.

Advantages of calculating ASR

ASR serves as a valuable tool in assessing the health and efficiency of a telecommunication network. It helps network operators identify issues, like network congestion, faulty equipment, or problematic routes, and implement timely fixes. A higher ASR generally indicates better network performance and customer satisfaction.

Disadvantages of calculating ASR

Although a useful tool, ASR should not be the only metric used to assess network performance. It does not account for call quality or duration, both of which are important for overall user experience. Additionally, a high ASR can sometimes mask issues like frequent short calls or call drops post connection, which might indicate other underlying network problems.