$\forall$${\it the\_w}$:World.
\\[0ex]FairFifo
\\[0ex]$\Rightarrow$ ($\forall$$m$:$\mathbb{N}$, $l$:IdLnk, $t$:$\mathbb{N}$. ($m$ $\leq$ $\parallel$snds($l$;$t$)$\parallel$) $\Rightarrow$ ($\exists$${\it t'}$:$\mathbb{N}$. (($t$ $\leq$ ${\it t'}$) \& ($m$ $\leq$ $\parallel$rcvs($l$;${\it t'}$)$\parallel$))))