317:(VCI). Routing information may be provided to the network nodes during the connection establishment phase, where the VCI is defined in tables in each node. Thus, the actual packet switching and data transfer can be taken care of by fast hardware, as opposed to slower software-based routing. Typically, this connection identifier is a small integer (for example, 10 bits for Frame Relay and 24 bits for ATM). This makes network switches substantially faster.
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313:, all data is sent over the same path during a communication session. Rather than using complete routing information for each packet (source and destination addresses) as in connectionless datagram switching such as conventional IP routers, a connection-oriented protocol identifies traffic flows only by a channel or data stream number, often denoted
222:(SMTP) is an example of a connection-oriented protocol in which, if a message is not delivered, an error report is sent to the sender, making it a reliable protocol. Because they can keep track of a conversation, connection-oriented protocols are sometimes described as stateful.
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mode communication. Due to the packet switching, the communication may suffer from variable bit rate and delay, due to varying traffic load and packet queue lengths. Connection-oriented communication does not necessarily imply
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such as IP, but still achieves in-order delivery of a byte-stream, by means of segment sequence numbering on the sender side, packet buffering and data packet reordering on the receiver side.
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switching mode, where all data packets belonging to the same traffic stream are delivered over the same path, and traffic flows are identified by some
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network layer protocol when it passes data in I-frames, but this combination is rare, and reliable-connectionless is uncommon in modern networks.
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Some connection-oriented protocols have been designed or altered to accommodate both connection-oriented and connectionless data.
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data link layer protocols. Reliable connectionless protocols exist as well, for example
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218:(MPLS) are examples of connection-oriented unreliable protocols.
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communication may also be connection-oriented, which is called
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Connection-oriented communication may be implemented with a
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417:"US Patent Application Publication 2005/0117529 A1"
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206:functions in case of missing or corrupted data.
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415:Ramos-Escano; et al. (June 2, 2005).
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108:Learn how and when to remove this message
390:Transparent Inter-process Communication
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380:Stream Control Transmission Protocol
355:Datagram Congestion Control Protocol
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375:Multiprotocol Label Switching
220:Simple Mail Transfer Protocol
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157:User Datagram Protocol
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449:Internet architecture
247:optical mesh networks
188:connection identifier
138:communication session
285:Connection-oriented
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438:Categories
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322:unreliable
251:bit stream
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243:SONET/SDH
155:(IP) and
98:June 2019
335:Examples
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