You're close. There's actually well understood technology for obfuscating the rate and frequency - the field for manipulating these variables is called "traffi

You're close. There's actually well understood technology for obfuscating the rate and frequency - the field for manipulating these variables is called "traffic analysis". One simple technique is to always transmit X packets/sec where Y packets/sec are real and the other packets are dummy packets (Y < X). If the channel is encrypted, it's impossible to distinguish the dummy traffic from the real traffic, and if you're over a VPN, it's difficult to identify the destination. A slightly more sophisticated approach is to vary X over time, to make it shaped like streaming video, for example, to obfuscate the fact that you're using traffic analysis countermeasures.