anisms (the Web is using the HTTP/TCP/IP protocol stack) directly depend upon the RTT. Additionally, shorter dis- tances between clients and servers (which is provided globally by distributed CDNs) provides lower delay and jitter budget due to fewer network nodes and network links that IP packets traverse from the source to the destination (both ways, from client to server, and vice versa, since TCP-based Internet traffic is fully duplex). 6.6.2 Traffic Management Approaches Although there are different scheduling and buffering mechanisms, in fact all traffic management is based on a decision and an intervention. For example, decision basis traffic management is control upon exceeding a weekly or monthly usage allowance for a given user. Then the intervention is the response of cutting the bitrate (lowering or stopping it) according to predefined policies (specified also in the SLA between the telecom operator and the end-user). Overall, one may distinguish among three common decision inputs: user QoS profile, which defines the QoS package that should be used for the given user; 6.6 QoS for Internet Access Service and Over-the-Top Data Services usage cap (e.g. daily, weekly, monthly, annual data allowance in MB, GB, or TB), which is usually set by the user's tariff (e.g. expensive tariffs have higher allowance, i.e. data caps, than cheaper ones); concrete traffic type (voice, video, Web, etc.). For traffic management purposes, in telecom operators' networks traffic management interventions [25] typically are used, which belong to two main types: IP packet prioritization. The queues of IP packets normally occur in network nodes (e.g. switches, routers, gateways), and in such cases higher priority traffic will be served with priority over lower priority traffic (which can be delayed or may suffer packet loss in cases of packet dropping due to buffer overflow). Packet prioritization is applied today in the core and transport networks. However, it is likely in future to move closer to the ultra-broadband access netwo