X.25 Some DSL modems ATM Ethernet supporting IEEE 802.1Q with Audio Video Bridging and Time-Sensitive Networking Wi-Fi supporting IEEE 802.11e HomePNA home networking over coax and phone wires The G.hn home networking standard provides QoS by means of contention-free transmission opportunities (CFTXOPs) which are allocated to flows which require QoS and which have negotiated a contract with the network controller. G.hn also supports non-QoS operation by means of contention-based time slots. End-to-end quality of service End-to-end quality of service can require a method of coordinating resource allocation between one autonomous system and another. The Internet Engineering Task Force (IETF) defined the Resource Reservation Protocol (RSVP) for bandwidth reservation as a proposed standard in 1997. RSVP is an end-to-end bandwidth reservation and admission control protocol. RSVP was not widely adopted due to scalability limitations. The more scalable traffic engineering version, RSVP-TE, is used in many networks to establish traffic-engineered Multiprotocol Label Switching (MPLS) label-switched paths. The IETF also defined Next Steps in Signaling (NSIS) with QoS signalling as a target. NSIS is a development and simplification of RSVP. Research consortia such as "end-to-end quality of service support over heterogeneous networks" (EuQoS, from 2004 through 2007) and fora such as the IPsphere Forum developed more mechanisms for handshaking QoS invocation from one domain to the next. IPsphere defined the Service Structuring Stratum (SSS) signaling bus in order to establish, invoke and (attempt to) assure network services. EuQoS conducted experiments to integrate Session Initiation Protocol, Next Steps in Signaling and IPsphere's SSS with an estimated cost of about 15.6 million Euro and published a book. A research project Multi Service Access Everywhere (MUSE) defined another QoS concept in a first phase from January 2004 through February 2006, and a second phase from January 2006 through 2007. Another research project named PlaNetS was proposed for European funding circa 2005. A broader European project called "Architecture and design for the future Internet" known as 4WARD had a budget estimated at 23.4 million Euro and was funded from January 2008 through June 2010. It included a "Quality of Service Theme" and published a book. Another European project, called WIDENS (Wireless Deployable Network System), proposed a bandwidth reservation approach for mobile wireless multirate adhoc networks. Limitations Strong cryptography network protocols such as Secure Sockets Layer, I2P, and virtual private networks obscure the data transferred using them. As all electronic commerce on the Internet requires the use of