Encontré este artículo que me pareció interesantisimo..
Se mencionan los fundamentos porque el encapsulamiento de tcp sobre tcp es una mala idea, habla de los tiempos en una capa con respecto a la otra (la del encapsulado); es un artículo de lectura recomendada…
Why TCP Over TCP Is A Bad Idea
A frequently occurring idea for IP tunneling applications is to run a protocol like PPP, which encapsulates IP packets in a format suited for a stream transport (like a modem line), over a TCP-based connection. This would be an easy solution for encrypting tunnels by running PPP over SSH, for which several recommendations already exist (one in the Linux HOWTO base, one on my own website, and surely several others). It would also be an easy way to compress arbitrary IP traffic, while datagram based compression has hard to overcome efficiency limits.

Unfortunately, it doesn’t work well. Long delays and frequent connection aborts are to be expected. Here is why.

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