This invention provides an image bearing member life detecting method capable of accurately detecting that the life of an image bearing member has expired or will expire soon, an image forming apparatus using the method, and a cartridge detachably attachable to the image forming apparatus. The circuit board includes an insulating layer and a wiring layer. In parallel with this active current generator, a stochastic process current generator is provided. The power reception device includes a load circuit. Mounting the fitting to the retainer can be accomplished by inserting posts of the retainer through holes of the fitting, or by mounting the fitting within a channel defined by mounting structures integral to the retainer. The security device acts as a conventional Firewall, NAT and PAT to isolate SIP User Agents on the private network from SIP User Agents on the public network and to Blacklist undesired callers.