An optical fiber cable for installation in a subterranean formation, where the temperature could be in excess of 150 degrees C. The optical fiber cable has an outer metallic jacket defining an elongated conduit with an internal elongated channel that receives an optical fiber. The optical fiber has two strands joined by a splice. A splice protector has a body with a passageway receiving the splice. The body has an outer region configured to be joined by a fusion weld to the outer metallic jacket.