  Compact canonical quantization on the light cone (DLCQ) is examined in the
limit of infinite periodicity lenth L. Pauli Jordan commutators are found to
approach continuum expressions with marginal non causal terms of order
$L^{-3/4}$ traced back to the handling of IR divergence through the elimination
of zero modes. In contrast direct quantization in the continuum (CLCQ) in terms
of field operators valued distributions is shown to provide the standard causal
result while at the same time ensuring consistent IR and UV renormalization.
