  This paper considers insertion and deletion channels with the additional
assumption that the channel input sequence is implicitly divided into segments
such that at most one edit can occur within a segment. No segment markers are
available in the received sequence. We propose code constructions for the
segmented deletion, segmented insertion, and segmented insertion-deletion
channels based on subsets of Varshamov-Tenengolts codes chosen with
pre-determined prefixes and/or suffixes. The proposed codes, constructed for
any finite alphabet, are zero-error and can be decoded segment-by-segment. We
also derive an upper bound on the rate of any zero-error code for the segmented
edit channel, in terms of the segment length. This upper bound shows that the
rate scaling of the proposed codes as the segment length increases is the same
as that of the maximal code.
