The Forward Error Correction (FEC) Framework (or FECFRAME) (RFC 6363) has been defined by the FECFRAME IETF WG to enable the use of FEC Encoding with real-time flows in a flexible manner. The original FECFRAME specification only considers the use of block FEC codes, wherein the input flow(s) is(are) segmented into a sequence of blocks and FEC encoding performed independently on a per-block basis. This document discusses an extension of FECFRAME in order to enable a sliding (potentially elastic) window encoding of the input flow(s), using convolutional FEC codes for the erasure channel, as an alternative to block FEC codes. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress."