This paper describes the implementation of order-wire functionality in NG-SDH devices ODS2G5 and OTS622 IRITEL. The paper also describes the operation of order-wire in networks with arbitrary topologies. as well as the configuration of order-wire functionality by using network management software SUNCE. The presented solution for order-wire functionality is compared with VoIP solutions. https://thebrickes.shop/product-category/mixer-attachment/