Eighteen distinct OC48 ITU 200GHz dense wavelength division multiplexing (DWDM) cards provide the ONS 15454 DWDM channel plan. Each OC-48 DWDM card provides one Telcordia-compliant, GR-253 SONET OC-48 port. The port operates at 2.49 Gbps over a single-mode fiber span. The card carries VT, concatenated, and non-concatenated payloads at STS-1, STS-3c, STS-6c, STS-12c, or STS-48c signal levels.You can install the OC48 ELR 200 GHz cards in any high-speed slot and provision the card as a drop or span card in a two-fiber or four-fiber BLSR, UPSR, or in an ADM (linear) configuration. Each OC48 ELR DWDM card uses extended long reach optics operating individually within the ITU-T 200 GHz grid. The OC48 DWDM cards are intended to be used in applications with long unregenerated spans of up to 200 km (with mid-span amplification). These transmission distances are achieved through the use of inexpensive optical amplifiers (flat gain amplifiers) such as erbium doped fiber amplifiers (EDFAs). Using co-located amplification, distances up to 200 km can be achieved for a single channel (160 km for 8 channels).