01 i.e. 10-3 Label H <0.0005 i.e. 5 x 10-4 Label M <40 or N/S <50 or N/S <0.0005 i.e. 5 x 10-4 Label L <0.001 i.e. 10-3 FD, one-way frame delay; MFD, mean frame delay; N/S, not specified; IFDV, inter-frame delay variation; FDR, frame delay range; FLR, frame loss ratio. End-to-End QoS Network Design QoS is always an end-to-end requirement. For the end-user, it is important that the QoS satisfies their needs and provides high user experience. Of course, that refers humans as end-users (regarding the end-user experience). For machine-to-machine (M2M) communication, the QoE has no meaning, but QoS has an end-to-end meaning and it is equally important as in the cases of human-to-human (e.g. telephony) or human-to-machine (e.g. Web browsing) communication. In general, services in telecommunications including IP-based platforms and NGNs are performed using two models [32]: Vertical model. This consists of three layers: lower protocol layers (physical and data-link layers as part of the network interfaces), the IP layer, and higher protocol layers (transport protocols such as UDP and TCP, up to the applications on the top). Horizontal model. This refers to horizontal configuration and interconnection of IP-based networks, which is primarily composed of two types of sections: network section and exchange links. The IP network components include source and desti- nation hosts, routers, and links (link is a P2P physical or virtual connection used for transporting IP packets between a pair of end hosts, which operates below the IP protocol layer). 4 QoS for Fixed Ultra-Broadband Understanding the performance features of both the horizontal and vertical model aspects is required for identifying service performance. The vertical model reflects the design of the application and the os of the given host or router (as network node) as well as connection of os with applications through the API via the sockets and connection to the network interfaces on the given machine below. Regarding the vertical model, QoS depends also on the 