Equation: Refer to ETSI TS 102 250-2 V2.2.1 (2011-04), Page 110 Speech Quality (MOS) Definition: The speech quality on call basis is an indicator representing the quantification of the end-to-end speech transmission quality of the mobile telephony service. This parameter computes the speech quality on a sample basis. Equation: The validation of the end-to-end quality is made using MOS scales. These scales describe the opinion of users with speech transmission and its troubles (noise, robot voice, echo, dropouts, etc.) according to ITU -T Recommendation P.862 in conjunction with ITUT Recommendation P.862.1, or according to ITU-T Recommendation P.863. The algorithm used should be reported. The speech quality measurement is taken per sample. An aggregation for measurement campaigns or parts of it should be made on speech sample basis. Listening-quality scale Quality of the speech Score Excellent 5 Good 4 Fair 3 Poor 2 Bad 1 The quantity evaluated from the scores (mean listening-quality opinion score, or simply meanpinion score) is represented by the symbol MOS. Refer to ITU-T RECOMMENDATION P.800 (08/1996) Note 3: The acoustic behaviour of terminals is not part of this speech quality measurement. SMS Service SMS Service Accessibility Definition: The SMS service accessibility denotes the probability that the end-user can access the SMS when requested while it is offered by display of the network indicator on the user equipment. Equation: Where: Regulations for Quality of Service of Cellular Mobile and Fixed Networks Services (Voice, SMS and 3G Data) 12