lines for business users, require QoS support end-to-end because Internet traffic is unpredictable (bursty by nature, with a high degree of self-similarity [40]). In short, IP-based networks cannot be planned in the same manner as PSTNs, which were developed for a single ToS, the voice (i.e. telephony). Additionally, emerging cloud computing and the Internet of Things may need certain QoS guarantees for specific types of users (business users, industry, etc.). Also, there is a need to guarantee QoS for access to the Internet as a whole. That is not access to particular applications over open Internet access (a particular application can be the Web, Skype, Viber, a social networking application, P2P applications such as BitTorrent, etc.) but to Internet access as a service provided by telecom operators (as ISPs) and used by end-users to access all applications and services available through the public Internet network. IP does not provide QoS mechanisms, but it has defined the ToS field in IPv4 and the DSCP field in IPv6 to specify QoS requirements on precedence, delay, throughput, and reliability, or to provide traffic differentiation. Overall, Internet architecture influences the QoS provisioning end-to-end. ASs are autonomous in every aspect regarding applied routing protocols and traffic management; only inter-AS routing is standardized to go with a single routing protocol (that is BGP-4). Which is the default (and native) QoS in Internet? Well, the default QoS approach is the best-effort approach (i.e. no QoS). That means every IP network gives its best-effort to transfer every IP packet that travels through it, however that is done, without any guarantees about whether the packet will reach its destination and what will be the qual- ity parameters associated with it (such as delay, losses). To introduce QoS in what was initially a no-QoS Internet, the framework included IntServ (as the oldest), DiffServ (most used as a concept), and MPLS-TE (the most used approach for QoS provisioning in transport IP network