The fixed-satellite service (FSS) plays an important role in providing reliable international digital communications. Because of the integration with the terrestrial facilities, a satellite link should be designed to fulfil requirements that are compatible with terrestrial systems. ITU-T Recommendation G.828 specifies performance parameters and objectives for international synchronous digital paths which are intended to carry synchronous digital hierarchy (SDH) and asynchronous transfer mode (ATM) traffic. In response to those objectives, this Recommendation gives guidance on bit-error probability (BEP) or bit-error rate (BER) design masks which can fully comply with the requirements of ITU-T Recommendation G.828.