ng the day when volume of Internet traffic in that network is highest). So, In this regard, peering and transit agreements of a given operator (i.e. ISP) influence end-to- end QoS and may require regulatory attention to ensure end-to-end QoS performance of services. With the transition of telecom operators' networks to all-IP networks, similar to TDM POI exchanges, IP eXchanges (IPXs) have been established in most countries. However, the IPX connects national telecom operators among themselves (typically with peering agreements) as well as connecting telecom operators with IP transit providers (e.g. with transit agreements). In many cases QoS regulation at the IPX is not present, especially because for transit traffic the IPX is also a "border" between two jurisdictions (e.g. each 7.4 KPIs for Real-Time Services Other IP networks Transit provider 1 Transit provider 2 Bandwidth for flow X = 12 Mbit/s Flow X bottleneck Bandwidth for flow X = 55 Mbit/s Bandwidth for flow X = 87 Mbit/s Data center of Access networks service provider End-user Figure 7.5 Internet interconnection points as possible bottleneck. country has its own jurisdiction over regulation of ICT services on its own territory). However, there are regional and global agreements between national authorities (e.g. NRAs and/or ministries for ICTs) regarding the QoS because overall the IP communi- cation (including public Internet and managed IP networks) is end-to-end and in most cases spans across multiple networks under different ICT jurisdictions. QoS parameters at the IPXs can be regulated and monitored within a country by the NRA. In gen- eral, end-to-end QoS can be achieved only through regional and global harmonization, including the IPXs and the networks attached to them. IP traffic includes also QoS-enabled VoIP, traffic from business users (e.g. VPN ser- vices), as well as IP traffic from IAS and traffic to/from CDNs and other data centers of the global service providers. Regarding the interconnection of different types of IP traf- fic, one shou