  Altermagnetic ruthenium oxide RuO$_{2}$ crystallizes with P4$_{2}$/mnm
symmetry. Here we discuss the lattice dynamics of this structure. We show and
discuss the phonon dispersion and density of states. The phonon dispersion
curves contain several Dirac nodal lines and highly degenerate Dirac points. We
present the characteristic frequencies and their irreducible representations at
the $\Gamma$ point. Theoretically obtained frequencies of the Raman active
modes nicely reproduce the ones reported experimentally.
