Performance: ipsec tranport mode over GRE or ipsec in tunnel mode?

[probie]

Anyone know which method is better for performance/throughput?

[cmb]

Not likely to be a measurable difference.

[rancor]

Transport is the preferred method and it saves you 20 bytes but since the recommended MTU size is 1400 on both GRE + IPsec (Transport mode) = 1440 and GRE + IPsec (Tunnel mode) = 1420 there is no bigger difference between them.

Just don't forget to set MTU on GRE interface or you will lose data

// rancor