548:. Given red data to send, the last segment of the red data is marked with an “end of red data” flag and a timer is started for that segment. Absent green data to send, the “end of block” flag is set, otherwise the green data is transmitted and the last segment of this part gets marked with the “end of block” flag. The receiver issues a report segment for the sender once it received the “end of red data” segment and all data is complete. Once the report segment has been transmitted, a timer is started. Upon arrival of the report segment, the sender cancels its timer, queues a report-acknowledgement for the receiver and informs the application that all red data has been successfully transmitted. Once the receiver receives the report-acknowledgement it cancels its timer and the transmission of the red data is completed. The transmission is completed if the “end of block” segment has arrived.
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481:(UDP), e.g. if used in a sensor network, in a private network (where bandwidth contestation isn’t an issue), or for software debug purposes. Therefore, it does not address issues like routing or congestion control. It was originally designed to support “long-haul” transmission in an interplanetary network; its design is based on experiences with the
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The LTP engine stores data in a queue, checks whether the link towards the destination is available and if so, starts the transmission. If the link is not available, the data remains in queue and transmission starts as soon as a so-called “link state cue” arrives, either from an underlying link layer
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part: It contains data that has to be transported reliably, has to be acknowledged by the receiver, and has to be held available until acknowledged. This could, e.g., be a header that contains important information to decode the following data, and whose corruption would render all following data
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It needs to be informed about link layer availability, round-trip time and communication schedules, basically requiring a management information base (MIB). LTP is highly stateful.
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part. It contains data that does not require reliable transport. Since reception of this data is not acknowledged, it can be discarded after transmission.
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LTP is designed to run directly over a data link layer (e.g. the
Advanced Orbiting Systems (AOS) Space Data Link Protocol). It can also run on the
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is a point to point protocol for use in deep space links. LTP is commonly seen as the standard underlying convergence layer protocol for the
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Unidirectional transmission sessions, circumvent high round-trip times or the inability of a peer communication node to transmit
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Scapy: the Python-based interactive packet manipulation program & library. Supports Python 2 & Python 3.: secdev/scapy
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Energy efficiency, as it only transmits if a link is available and distinguishes between important and unimportant data.
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Its timers work together with communication schedules and can be suspended whenever a scheduled link outage occurs.
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No exchange of messages to perform negotiation. The protocol avoids this process to avoid delays due to high
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Unreliable data transport for less important data (such as image pixels—a damaged pixel can be overcome)
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The application divides its data to send into two parts (either part may have a size of 0):
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Reliable data transport for important data (such as a file header)
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has an LTP contrib module, contributed by the MITRE Corporation.
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RFC 5327: Licklider
Transmission Protocol—Security Extensions
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Developed for space communication, its features are:
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LTP is named in honor of
American computer scientist
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408:but its sources remain unclear because it lacks
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439:Learn how and when to remove this message
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502:. It also avoids link underutilisation.
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452:Licklider Transmission Protocol
616:"AOS SPACE DATA LINK PROTOCOL"
1:
467:Joseph Carl Robnett Licklider
483:CCSDS File Delivery Protocol
546:management information base
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725:Transport layer protocols
571:Jet Propulsion Laboratory
569:ION, written in C by the
563:reference implementations
557:Reference implementations
580:LTPlib, written in C by
394:This article includes a
705:ION, University of Ohio
582:Trinity College, Dublin
423:more precise citations.
23:Internet protocol suite
16:Point to point protocol
710:LTPlib Trinity College
479:User Datagram Protocol
589:Other implementations
669:, SecDev, 2019-03-05
653:. 18 November 2021.
573:and maintained at
396:list of references
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415:Please help
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421:introducing
673:2019-03-05
602:References
544:or from a
429:March 2019
312:Link layer
719:Category
629:13 March
561:The two
539:Protocol
527:useless.
485:(CFDP).
645:"Scapy"
625:. CCSDS
417:improve
342:more...
326:Tunnels
302:more...
235:more...
185:more...
174:TLS/SSL
129:ONC/RPC
66: (
650:GitHub
473:Design
169:Telnet
68:HTTP/3
619:(PDF)
595:Scapy
532:green
402:, or
296:IPsec
74:HTTPS
631:2022
291:IGMP
271:ICMP
229:QUIC
224:RSVP
219:SCTP
214:DCCP
179:XMPP
159:SNMP
154:SMTP
139:RTSP
114:OSPF
104:NNTP
99:MQTT
94:MGCP
89:LDAP
79:IMAP
64:HTTP
44:DHCP
524:red
336:MAC
331:PPP
321:ARP
286:ECN
281:NDP
209:UDP
204:TCP
164:SSH
149:SIP
144:RIP
134:RTP
124:PTP
119:POP
109:NTP
84:IRC
59:FTP
54:DNS
39:BGP
721::
647:.
621:.
530:a
522:a
469:.
406:,
398:,
275:v6
264:v6
259:v4
254:IP
48:v6
633:.
584:.
577:.
458:(
442:)
436:(
431:)
427:(
413:.
370:e
363:t
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273:(
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50:)
46:(
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.