Caller ID said Viper Networks. Silence when I said hello. Said hello again, man with accent (Indian?) tried to pronounce my name. I kept asking, What does this call concern? Man said, How are you today? .What is this about? I asked again. Man: Are you diabetic? I asked if he was aware I'm on the do-not-call list. Silence. I said it again, then: Do you understand? Hung up.