Embodiments of the present prevention disclose a service processing method, a communication system, and relevant devices to enable the user to more conveniently set ring tones and improve system security. The method includes: a management client located in a user terminal obtains a ring tone setting processing request of a user; and the management client sends the ring tone setting processing request to a service server through a mobile network so that the service server can perform corresponding processing according to the ring tone setting processing request. A communication system and the relevant devices are also disclosed in the embodiments of the present prevention. The embodiments of the present invention can enable the user to conveniently set the tone, reduce unnecessary network traffic, and improve system security.