ith different geographic distance between different pairs of Els and that has a significant influence on the frame delay (the longer the distance between the EIs, the larger the delay). The defined implementa- tion agreement (IA), according to the MEF terminology, is created to provide guidance to service providers, telecom operators, and subscribers by specifying five sets of CPOs called performance tiers (PTs), given in Table 4.6. Each set includes objectives for seven performance metrics for P2P and multi-point CPOs. An example of bandwidth profiles for mobile backhaul (e.g. for 4G) is given in Figure 4.8. The extension of the Carrier Ethernet QoS is via the usage of bandwidth profiles and traffic management techniques, based on quantification of delay, delay variation, Ethernet frame loss ratio, network availability, and SO on. The CoS models give the possibility to define the SLA at the UNI. The MEF defines three particular CoS names, which are also noted as CoS labels: H (High) label. This is targeted to applications which are very sensitive to delay, delay variation, and losses, such as mobile backhaul control traffic and VoIP. M (Medium) label. This is targeted to applications which are less sensitive (i.e. more tolerant) to delay and/or delay variation, but are sensitive to losses. These are critical data applications and near real-time ones. L (Low) label. This is targeted to non-critical applications, which are more tolerant to delay, delay variation, and losses. In Carrier Ethernet there is a CoS frame set (CoS FS) which is defined as association of a CoS name and a set of ordered end-point pairs (OEPPs). The CoS EF represents all Ethernet frames which traverse between a particular set of EVC/OVC endpoints within a particular CoS. Each of the CoS FSs within a given EVC or OVC should be associated Table 4.6 Performance tiers for Carrier Ethernet. Performance Performance tier (PT) number tier (PT) name Distance, delay PT0.3 City PT <75km, 0.6 ms Metro PT <250 km, 2 ms Regional PT <1200 km, 8 ms Continen