3 ms·

I'm not sure if only the client does the padding, or if the padding also occurs at intermediate hops, but Tor does randomly pad traffic by default (from manpage

I'm not sure if only the client does the padding, or if the padding also occurs at intermediate hops, but Tor does randomly pad traffic by default (from manpage of torrc): CircuitPadding 0|1 If set to 0, Tor will not pad client circuits with additional cover traffic. Only clients may set this option. This option should be offered via the UI to mobile users for use where bandwidth may be expensive. If set to 1, padding will be negotiated as per the consensus and relay support (unlike ConnectionPadding, CircuitPadding cannot be force-enabled). (Default: 1) ReducedCircuitPadding 0|1 If set to 1, Tor will only use circuit padding algorithms that have low overhead. Only clients may set this option. This option should be offered via the UI to mobile users for use where bandwidth may be expensive. (Default: 0)

londons_explore 4y ago
Padding is always positive. That means every packet will always have its size increased, but never decreased. With a mixture of packet sizes, and flows, it's still only typically ~30 or so packets to identify a flow with this padding. That means a typical user might have anonymity for perhaps 1 additional second using this option... Basically - this option doesn't serve it's intended purpose.