encryption would prevent the modem from seeing it when someone sends it, but such a short string will inevitably appear once in a while in ciphertext too. so, it would actually make it disconnect at random times instead :)
(edit: actually at seven bytes i guess it would only occur once in every 72PB on average…)
These articles were stolen, by the paywall operators. Elbakyan rescued them from the thieves. 🎉