The Packet Transport Network(PTN) technology includes Transport Multi-Protocol Label Switching(T-MPLS) and Provider Backbone Transport(PBT).T-MPLS is the simplified and reformed Multi-Protocol Label Switching(MPLS).It...The Packet Transport Network(PTN) technology includes Transport Multi-Protocol Label Switching(T-MPLS) and Provider Backbone Transport(PBT).T-MPLS is the simplified and reformed Multi-Protocol Label Switching(MPLS).It drops MPLS’connectionless features and its transport-unrelated forwarding processing,but adds the network model of the transport layer,protection switching and Operation,Administration and Maintenance(OAM) functionality.PBT enforces both OAM and protection functions,adds Time Division Multiplexing(TDM) business simulation and clock functions,and strengthens multi-service support capability.But PBT has no functions of traditional Ethernet address learning,address broadcast and Spanning Tree Protocol(STP).Both T-MPLS and PBT can well satisfy the requirements of packet transport.Compared to PBT,T-MPLS has better OAM functions.展开更多
The Metro Ethernet Forum(MEF) put forward the concept of Carrier Ethernet(CE) to improve Ethernet technology and make it a transmission convergence layer solution for Next Generation Network(NGN).Provider Backbone Tra...The Metro Ethernet Forum(MEF) put forward the concept of Carrier Ethernet(CE) to improve Ethernet technology and make it a transmission convergence layer solution for Next Generation Network(NGN).Provider Backbone Transport(PBT) is the result of the enhancement and improvement of the early Ethernet technologies and it is the new version of CE implementation technology and standard which is promising.Through studying the PBT-related technologies,PBT network structure,PBT advantages as the transmission convergence layer solution and its trend of future development,it is concluded that PBT can be used as the preferred technology of the transmission convergence layer in the NGN,though there are some problems to be solved for PBT.展开更多
The world has entered an era featured with fast transportation, instant communication, and prompt technological revolution, the further advancement of which all relies fundamentally, yet, on the development of cost-ef...The world has entered an era featured with fast transportation, instant communication, and prompt technological revolution, the further advancement of which all relies fundamentally, yet, on the development of cost-effective energy resources allowing for durable and high-rate energy supply. Current battery and fuel cell systems are challenged by a few issues characterized either of insufficient energy capacity or of operation instability and, thus, are not ideal for highly-demanded applications, such as electrical vehicles and portable electronic devices. Inefficient mass transfer in energy conversion/storage devices has been the key factor leading to these aforementioned challenges.展开更多
文摘The Packet Transport Network(PTN) technology includes Transport Multi-Protocol Label Switching(T-MPLS) and Provider Backbone Transport(PBT).T-MPLS is the simplified and reformed Multi-Protocol Label Switching(MPLS).It drops MPLS’connectionless features and its transport-unrelated forwarding processing,but adds the network model of the transport layer,protection switching and Operation,Administration and Maintenance(OAM) functionality.PBT enforces both OAM and protection functions,adds Time Division Multiplexing(TDM) business simulation and clock functions,and strengthens multi-service support capability.But PBT has no functions of traditional Ethernet address learning,address broadcast and Spanning Tree Protocol(STP).Both T-MPLS and PBT can well satisfy the requirements of packet transport.Compared to PBT,T-MPLS has better OAM functions.
文摘The Metro Ethernet Forum(MEF) put forward the concept of Carrier Ethernet(CE) to improve Ethernet technology and make it a transmission convergence layer solution for Next Generation Network(NGN).Provider Backbone Transport(PBT) is the result of the enhancement and improvement of the early Ethernet technologies and it is the new version of CE implementation technology and standard which is promising.Through studying the PBT-related technologies,PBT network structure,PBT advantages as the transmission convergence layer solution and its trend of future development,it is concluded that PBT can be used as the preferred technology of the transmission convergence layer in the NGN,though there are some problems to be solved for PBT.
文摘The world has entered an era featured with fast transportation, instant communication, and prompt technological revolution, the further advancement of which all relies fundamentally, yet, on the development of cost-effective energy resources allowing for durable and high-rate energy supply. Current battery and fuel cell systems are challenged by a few issues characterized either of insufficient energy capacity or of operation instability and, thus, are not ideal for highly-demanded applications, such as electrical vehicles and portable electronic devices. Inefficient mass transfer in energy conversion/storage devices has been the key factor leading to these aforementioned challenges.
