SlideShare a Scribd company logo

IETF 118: Starlink Protocol Performance

APNIC
APNIC
APNICAPNIC

APNIC Chief Scientist Geoff Huston presents on Starlink Protocol Performance at IETF 118, held from 4 to 10 November in Prague, Czech Republic.

IETF 118: Starlink Protocol Performance

1 of 22
Download to read offline
Starlink Protocol
Performance
Geoff Huston
APNIC
Low Earth Orbit
• LEO satellites are stationed between 160km and 2,000km in altitude
• High enough to stop them slowing down by “grazing” the denser parts of the earth’s ionosphere
• Not so high that they lose the radiation protection afforded by the Inner Van Allen belt.
• At a height of 550km, the minimum signal propagation delay to reach the satellite and back is 3.7ms, and at
the horizon its 18ms
screenshot from starwatch app
Image - spacex
2
Starlink Constellation
If you use a minimum angle of elevation of 25o then at an
altitude of 550km each satellite spans a terrestrial
footprint of no more than ~900Km radius, or 2M K2
At a minimum, a LEO satellite constellation needs 500
satellites to provide coverage of all parts of the earth’s
surface
For high quality coverage the constellation will need 6x-
20x that number (or more!)
3
Starlink Constellation
• 4,276 in-service operational spacecraft, operating at an altitude of 550km
https://satellitemap.space/
4
Looking Up
Starlink tracks satellites with a minimum
elevation of 25o.
There are between 30 – 50 visible Starlink
satellites at any point on the surface
between latitudes 56o North and South
Each satellite traverses the visible aperture
for a maximum of ~3 minutes
5
Starlink Scheduling
• A satellite is assigned to a user terminal in 15 second time slots
• Tracking of a satellite (by phased array focussing) works across 11
degrees of arc per satellite in each 15 second slot
client
11o
15 seconds
6
Ad

Recommended

RIPE 87: On Low Earth Orbit Satellites (LEOs) and Starlink
RIPE 87: On Low Earth Orbit Satellites (LEOs) and StarlinkRIPE 87: On Low Earth Orbit Satellites (LEOs) and Starlink
RIPE 87: On Low Earth Orbit Satellites (LEOs) and StarlinkAPNIC
 
VNNIC Internet Day 2023: On LEOs and Starlink
VNNIC Internet Day 2023: On LEOs and StarlinkVNNIC Internet Day 2023: On LEOs and Starlink
VNNIC Internet Day 2023: On LEOs and StarlinkAPNIC
 
40th TWNIC OPM: On LEOs (Low Earth Orbits) and Starlink Download
40th TWNIC OPM: On LEOs (Low Earth Orbits) and Starlink Download40th TWNIC OPM: On LEOs (Low Earth Orbits) and Starlink Download
40th TWNIC OPM: On LEOs (Low Earth Orbits) and Starlink DownloadAPNIC
 
mnNOG 2023: On GEOs, LEOs and Starlink
mnNOG 2023: On GEOs, LEOs and StarlinkmnNOG 2023: On GEOs, LEOs and Starlink
mnNOG 2023: On GEOs, LEOs and StarlinkAPNIC
 

More Related Content

Similar to IETF 118: Starlink Protocol Performance

RIPE 80: Buffers and Protocols
RIPE 80: Buffers and ProtocolsRIPE 80: Buffers and Protocols
RIPE 80: Buffers and ProtocolsAPNIC
 
Satellite communication
Satellite communicationSatellite communication
Satellite communicationRashmi Deoli
 
SATELLITE COMMUNICATION AND IT'S APPLICATION IN GPS
SATELLITE COMMUNICATION AND IT'S APPLICATION IN GPSSATELLITE COMMUNICATION AND IT'S APPLICATION IN GPS
SATELLITE COMMUNICATION AND IT'S APPLICATION IN GPSArkaprava Jana
 
O3b sspi vsat_day_presentation_2012
O3b sspi vsat_day_presentation_2012O3b sspi vsat_day_presentation_2012
O3b sspi vsat_day_presentation_2012SSPI Brasil
 
ORBCOMM Satellite System
ORBCOMM Satellite SystemORBCOMM Satellite System
ORBCOMM Satellite SystemAkram Ahmed
 
Satellite communication
Satellite communicationSatellite communication
Satellite communicationaditi sehgal
 
PRESENTATION ON SATELLITE COMMUNICATION
PRESENTATION ON SATELLITE COMMUNICATIONPRESENTATION ON SATELLITE COMMUNICATION
PRESENTATION ON SATELLITE COMMUNICATIONVarun Gangishetty
 
Satellite communication
Satellite communicationSatellite communication
Satellite communicationNeeda Multani
 
IP based communications over satellites
IP based communications over satellitesIP based communications over satellites
IP based communications over satellitesBektaş Şahin
 
AROSAT_updated-spacesegment_presentation_NO_loghi
AROSAT_updated-spacesegment_presentation_NO_loghiAROSAT_updated-spacesegment_presentation_NO_loghi
AROSAT_updated-spacesegment_presentation_NO_loghiStefano Coltellacci
 
Telecom lect 8
Telecom lect 8Telecom lect 8
Telecom lect 8Shiraz316
 
APPLICATION OF MECHATRONICS IN DEFENCE
APPLICATION OF MECHATRONICS IN DEFENCE APPLICATION OF MECHATRONICS IN DEFENCE
APPLICATION OF MECHATRONICS IN DEFENCE Swapnil Shahade
 
Julie.webster
Julie.websterJulie.webster
Julie.websterNASAPMC
 

Similar to IETF 118: Starlink Protocol Performance (20)

Satellite1
Satellite1Satellite1
Satellite1
 
satellite.ppt
satellite.pptsatellite.ppt
satellite.ppt
 
Satellite
SatelliteSatellite
Satellite
 
RIPE 80: Buffers and Protocols
RIPE 80: Buffers and ProtocolsRIPE 80: Buffers and Protocols
RIPE 80: Buffers and Protocols
 
Satellite communication
Satellite communicationSatellite communication
Satellite communication
 
SATELLITE COMMUNICATION AND IT'S APPLICATION IN GPS
SATELLITE COMMUNICATION AND IT'S APPLICATION IN GPSSATELLITE COMMUNICATION AND IT'S APPLICATION IN GPS
SATELLITE COMMUNICATION AND IT'S APPLICATION IN GPS
 
Lecture 10.ppt
Lecture 10.pptLecture 10.ppt
Lecture 10.ppt
 
O3b sspi vsat_day_presentation_2012
O3b sspi vsat_day_presentation_2012O3b sspi vsat_day_presentation_2012
O3b sspi vsat_day_presentation_2012
 
ORBCOMM Satellite System
ORBCOMM Satellite SystemORBCOMM Satellite System
ORBCOMM Satellite System
 
Satellite communication
Satellite communicationSatellite communication
Satellite communication
 
PRESENTATION ON SATELLITE COMMUNICATION
PRESENTATION ON SATELLITE COMMUNICATIONPRESENTATION ON SATELLITE COMMUNICATION
PRESENTATION ON SATELLITE COMMUNICATION
 
Satellite communication
Satellite communicationSatellite communication
Satellite communication
 
IP based communications over satellites
IP based communications over satellitesIP based communications over satellites
IP based communications over satellites
 
AROSAT_updated-spacesegment_presentation_NO_loghi
AROSAT_updated-spacesegment_presentation_NO_loghiAROSAT_updated-spacesegment_presentation_NO_loghi
AROSAT_updated-spacesegment_presentation_NO_loghi
 
Satellite systems
Satellite systemsSatellite systems
Satellite systems
 
Telecom lect 8
Telecom lect 8Telecom lect 8
Telecom lect 8
 
Poster- QCS
Poster- QCSPoster- QCS
Poster- QCS
 
APPLICATION OF MECHATRONICS IN DEFENCE
APPLICATION OF MECHATRONICS IN DEFENCE APPLICATION OF MECHATRONICS IN DEFENCE
APPLICATION OF MECHATRONICS IN DEFENCE
 
Julie.webster
Julie.websterJulie.webster
Julie.webster
 
Intd to Sat Commn
Intd to Sat CommnIntd to Sat Commn
Intd to Sat Commn
 

More from APNIC

APAN 57: APNIC Report at APAN 57, Bangkok, Thailand
APAN 57: APNIC Report at APAN 57, Bangkok, ThailandAPAN 57: APNIC Report at APAN 57, Bangkok, Thailand
APAN 57: APNIC Report at APAN 57, Bangkok, ThailandAPNIC
 
AINTEC 2023: Networking in the Penumbra!
AINTEC 2023: Networking in the Penumbra!AINTEC 2023: Networking in the Penumbra!
AINTEC 2023: Networking in the Penumbra!APNIC
 
CNIRC 2023: Global and Regional IPv6 Deployment 2023
CNIRC 2023: Global and Regional IPv6 Deployment 2023CNIRC 2023: Global and Regional IPv6 Deployment 2023
CNIRC 2023: Global and Regional IPv6 Deployment 2023APNIC
 
AFSIG 2023: APNIC Foundation and support for Internet development
AFSIG 2023: APNIC Foundation and support for Internet developmentAFSIG 2023: APNIC Foundation and support for Internet development
AFSIG 2023: APNIC Foundation and support for Internet developmentAPNIC
 
AFNOG 1: Afghanistan IP Deployment Status
AFNOG 1: Afghanistan IP Deployment StatusAFNOG 1: Afghanistan IP Deployment Status
AFNOG 1: Afghanistan IP Deployment StatusAPNIC
 
AFSIG 2023: Internet routing and addressing
AFSIG 2023: Internet routing and addressingAFSIG 2023: Internet routing and addressing
AFSIG 2023: Internet routing and addressingAPNIC
 
AFSIG 2023: APNIC - Registry & Development
AFSIG 2023: APNIC - Registry & DevelopmentAFSIG 2023: APNIC - Registry & Development
AFSIG 2023: APNIC - Registry & DevelopmentAPNIC
 
Afghanistan IGF 2023: The ABCs and importance of cybersecurity
Afghanistan IGF 2023: The ABCs and importance of cybersecurityAfghanistan IGF 2023: The ABCs and importance of cybersecurity
Afghanistan IGF 2023: The ABCs and importance of cybersecurityAPNIC
 
IDNIC OPM 2023: IPv6 deployment planning and security considerations
IDNIC OPM 2023: IPv6 deployment planning and security considerationsIDNIC OPM 2023: IPv6 deployment planning and security considerations
IDNIC OPM 2023: IPv6 deployment planning and security considerationsAPNIC
 
IDNIC OPM 2023 - Internet Number Registry System
IDNIC OPM 2023 - Internet Number Registry SystemIDNIC OPM 2023 - Internet Number Registry System
IDNIC OPM 2023 - Internet Number Registry SystemAPNIC
 
PacNOG 32: Resource Public Key Infrastructure (RPKI) in 30 minutes or less
PacNOG 32: Resource Public Key Infrastructure (RPKI) in 30 minutes or lessPacNOG 32: Resource Public Key Infrastructure (RPKI) in 30 minutes or less
PacNOG 32: Resource Public Key Infrastructure (RPKI) in 30 minutes or lessAPNIC
 
40th TWNIC Open Policy Meeting: APNIC PDP update
40th TWNIC Open Policy Meeting: APNIC PDP update40th TWNIC Open Policy Meeting: APNIC PDP update
40th TWNIC Open Policy Meeting: APNIC PDP updateAPNIC
 
40th TWNIC Open Policy Meeting: A quick look at QUIC
40th TWNIC Open Policy Meeting: A quick look at QUIC40th TWNIC Open Policy Meeting: A quick look at QUIC
40th TWNIC Open Policy Meeting: A quick look at QUICAPNIC
 
HKNOG 12.0: RPKI Actions Required by HK Networks
HKNOG 12.0: RPKI Actions Required by HK NetworksHKNOG 12.0: RPKI Actions Required by HK Networks
HKNOG 12.0: RPKI Actions Required by HK NetworksAPNIC
 
KHNOG 5: RPKI Status Update
KHNOG 5: RPKI Status UpdateKHNOG 5: RPKI Status Update
KHNOG 5: RPKI Status UpdateAPNIC
 
KHNOG 5: APNIC Services
KHNOG 5: APNIC ServicesKHNOG 5: APNIC Services
KHNOG 5: APNIC ServicesAPNIC
 
PITA Strategy Forum 2023: Internet resilience
PITA Strategy Forum 2023: Internet resiliencePITA Strategy Forum 2023: Internet resilience
PITA Strategy Forum 2023: Internet resilienceAPNIC
 
SANOG 40: DDoS in South Asia
SANOG 40: DDoS in South AsiaSANOG 40: DDoS in South Asia
SANOG 40: DDoS in South AsiaAPNIC
 
SANOG 40: RPKI in South Asia
SANOG 40: RPKI in South AsiaSANOG 40: RPKI in South Asia
SANOG 40: RPKI in South AsiaAPNIC
 
RenasCON 2023: Learning from honeypots
RenasCON 2023: Learning from honeypotsRenasCON 2023: Learning from honeypots
RenasCON 2023: Learning from honeypotsAPNIC
 

More from APNIC (20)

APAN 57: APNIC Report at APAN 57, Bangkok, Thailand
APAN 57: APNIC Report at APAN 57, Bangkok, ThailandAPAN 57: APNIC Report at APAN 57, Bangkok, Thailand
APAN 57: APNIC Report at APAN 57, Bangkok, Thailand
 
AINTEC 2023: Networking in the Penumbra!
AINTEC 2023: Networking in the Penumbra!AINTEC 2023: Networking in the Penumbra!
AINTEC 2023: Networking in the Penumbra!
 
CNIRC 2023: Global and Regional IPv6 Deployment 2023
CNIRC 2023: Global and Regional IPv6 Deployment 2023CNIRC 2023: Global and Regional IPv6 Deployment 2023
CNIRC 2023: Global and Regional IPv6 Deployment 2023
 
AFSIG 2023: APNIC Foundation and support for Internet development
AFSIG 2023: APNIC Foundation and support for Internet developmentAFSIG 2023: APNIC Foundation and support for Internet development
AFSIG 2023: APNIC Foundation and support for Internet development
 
AFNOG 1: Afghanistan IP Deployment Status
AFNOG 1: Afghanistan IP Deployment StatusAFNOG 1: Afghanistan IP Deployment Status
AFNOG 1: Afghanistan IP Deployment Status
 
AFSIG 2023: Internet routing and addressing
AFSIG 2023: Internet routing and addressingAFSIG 2023: Internet routing and addressing
AFSIG 2023: Internet routing and addressing
 
AFSIG 2023: APNIC - Registry & Development
AFSIG 2023: APNIC - Registry & DevelopmentAFSIG 2023: APNIC - Registry & Development
AFSIG 2023: APNIC - Registry & Development
 
Afghanistan IGF 2023: The ABCs and importance of cybersecurity
Afghanistan IGF 2023: The ABCs and importance of cybersecurityAfghanistan IGF 2023: The ABCs and importance of cybersecurity
Afghanistan IGF 2023: The ABCs and importance of cybersecurity
 
IDNIC OPM 2023: IPv6 deployment planning and security considerations
IDNIC OPM 2023: IPv6 deployment planning and security considerationsIDNIC OPM 2023: IPv6 deployment planning and security considerations
IDNIC OPM 2023: IPv6 deployment planning and security considerations
 
IDNIC OPM 2023 - Internet Number Registry System
IDNIC OPM 2023 - Internet Number Registry SystemIDNIC OPM 2023 - Internet Number Registry System
IDNIC OPM 2023 - Internet Number Registry System
 
PacNOG 32: Resource Public Key Infrastructure (RPKI) in 30 minutes or less
PacNOG 32: Resource Public Key Infrastructure (RPKI) in 30 minutes or lessPacNOG 32: Resource Public Key Infrastructure (RPKI) in 30 minutes or less
PacNOG 32: Resource Public Key Infrastructure (RPKI) in 30 minutes or less
 
40th TWNIC Open Policy Meeting: APNIC PDP update
40th TWNIC Open Policy Meeting: APNIC PDP update40th TWNIC Open Policy Meeting: APNIC PDP update
40th TWNIC Open Policy Meeting: APNIC PDP update
 
40th TWNIC Open Policy Meeting: A quick look at QUIC
40th TWNIC Open Policy Meeting: A quick look at QUIC40th TWNIC Open Policy Meeting: A quick look at QUIC
40th TWNIC Open Policy Meeting: A quick look at QUIC
 
HKNOG 12.0: RPKI Actions Required by HK Networks
HKNOG 12.0: RPKI Actions Required by HK NetworksHKNOG 12.0: RPKI Actions Required by HK Networks
HKNOG 12.0: RPKI Actions Required by HK Networks
 
KHNOG 5: RPKI Status Update
KHNOG 5: RPKI Status UpdateKHNOG 5: RPKI Status Update
KHNOG 5: RPKI Status Update
 
KHNOG 5: APNIC Services
KHNOG 5: APNIC ServicesKHNOG 5: APNIC Services
KHNOG 5: APNIC Services
 
PITA Strategy Forum 2023: Internet resilience
PITA Strategy Forum 2023: Internet resiliencePITA Strategy Forum 2023: Internet resilience
PITA Strategy Forum 2023: Internet resilience
 
SANOG 40: DDoS in South Asia
SANOG 40: DDoS in South AsiaSANOG 40: DDoS in South Asia
SANOG 40: DDoS in South Asia
 
SANOG 40: RPKI in South Asia
SANOG 40: RPKI in South AsiaSANOG 40: RPKI in South Asia
SANOG 40: RPKI in South Asia
 
RenasCON 2023: Learning from honeypots
RenasCON 2023: Learning from honeypotsRenasCON 2023: Learning from honeypots
RenasCON 2023: Learning from honeypots
 

Recently uploaded

Modern Red Teaming - subverting mature defenses on a budget
Modern Red Teaming - subverting mature defenses on a budgetModern Red Teaming - subverting mature defenses on a budget
Modern Red Teaming - subverting mature defenses on a budgetmatt806068
 
Earn 3000 dollars per month
Earn 3000 dollars per monthEarn 3000 dollars per month
Earn 3000 dollars per monthplaycorea108
 
UGBINTERNETBANKING FACILITY LAUNCHED.pptx
UGBINTERNETBANKING FACILITY LAUNCHED.pptxUGBINTERNETBANKING FACILITY LAUNCHED.pptx
UGBINTERNETBANKING FACILITY LAUNCHED.pptxRiteshsahu101
 
[Hackersuli]Privacy on the blockchain
[Hackersuli]Privacy on the blockchain[Hackersuli]Privacy on the blockchain
[Hackersuli]Privacy on the blockchainhackersuli
 
history of tau gamma architect.1968.....
history of tau gamma architect.1968.....history of tau gamma architect.1968.....
history of tau gamma architect.1968.....josephiigo
 

Recently uploaded (8)

Modern Red Teaming - subverting mature defenses on a budget
Modern Red Teaming - subverting mature defenses on a budgetModern Red Teaming - subverting mature defenses on a budget
Modern Red Teaming - subverting mature defenses on a budget
 
Earn 3000 dollars per month
Earn 3000 dollars per monthEarn 3000 dollars per month
Earn 3000 dollars per month
 
B1 Evaluation.docx
B1 Evaluation.docxB1 Evaluation.docx
B1 Evaluation.docx
 
Riesgos online
Riesgos onlineRiesgos online
Riesgos online
 
INTERNET
INTERNETINTERNET
INTERNET
 
UGBINTERNETBANKING FACILITY LAUNCHED.pptx
UGBINTERNETBANKING FACILITY LAUNCHED.pptxUGBINTERNETBANKING FACILITY LAUNCHED.pptx
UGBINTERNETBANKING FACILITY LAUNCHED.pptx
 
[Hackersuli]Privacy on the blockchain
[Hackersuli]Privacy on the blockchain[Hackersuli]Privacy on the blockchain
[Hackersuli]Privacy on the blockchain
 
history of tau gamma architect.1968.....
history of tau gamma architect.1968.....history of tau gamma architect.1968.....
history of tau gamma architect.1968.....
 

IETF 118: Starlink Protocol Performance

  • 2. Low Earth Orbit • LEO satellites are stationed between 160km and 2,000km in altitude • High enough to stop them slowing down by “grazing” the denser parts of the earth’s ionosphere • Not so high that they lose the radiation protection afforded by the Inner Van Allen belt. • At a height of 550km, the minimum signal propagation delay to reach the satellite and back is 3.7ms, and at the horizon its 18ms screenshot from starwatch app Image - spacex 2
  • 3. Starlink Constellation If you use a minimum angle of elevation of 25o then at an altitude of 550km each satellite spans a terrestrial footprint of no more than ~900Km radius, or 2M K2 At a minimum, a LEO satellite constellation needs 500 satellites to provide coverage of all parts of the earth’s surface For high quality coverage the constellation will need 6x- 20x that number (or more!) 3
  • 4. Starlink Constellation • 4,276 in-service operational spacecraft, operating at an altitude of 550km https://satellitemap.space/ 4
  • 5. Looking Up Starlink tracks satellites with a minimum elevation of 25o. There are between 30 – 50 visible Starlink satellites at any point on the surface between latitudes 56o North and South Each satellite traverses the visible aperture for a maximum of ~3 minutes 5
  • 6. Starlink Scheduling • A satellite is assigned to a user terminal in 15 second time slots • Tracking of a satellite (by phased array focussing) works across 11 degrees of arc per satellite in each 15 second slot client 11o 15 seconds 6
  • 7. Starlink Scheduling • Latency changes on each satellite switch • If we take the minimum latency on each 15 second scheduling interval, we can expose the effects of the switching interval on latency • Across the 15 second interval there will be a drift in latency according to the satellite’s track and the distance relative to the two earth points • Other user traffic will also impact on latency, and also the effects of a large buffer in the user modem
  • 8. Starlink Spot Beams • Each spacecraft 2,000 MHz of spectrum for user downlink and splits it into 8x channels of 250 MHz each • Each satellite has 3 downlink antennas and 1 uplink antennas, and each can do 8 beams x 2 polarizations, for a total of 48 beams down and 16 up. 8 “Unveiling Beamforming Strategies of Starlink LEO Satellites” https://people.engineering.osu.edu/sites/default/files/2022-10/Kassas_Unveiling_Beamforming_Strategies_of_Starlink_LEO_Satellites.pdf
  • 9. Starlink’s reports $ starlink-grpc-tools/dish_grpc_text.py -v status id: ut01000000-00000000-005dd555 hardware_version: rev3_proto2 software_version: 5a923943-5acb-4d05-ac58-dd93e72b7862.uterm.release state: CONNECTED uptime: 481674 snr: seconds_to_first_nonempty_slot: 0.0 pop_ping_drop_rate: 0.0 downlink_throughput_bps: 16693.330078125 uplink_throughput_bps: 109127.3984375 pop_ping_latency_ms: 49.5 Alerts bit field: 0 fraction_obstructed: 0.04149007424712181 currently_obstructed: False seconds_obstructed: obstruction_duration: 1.9579976797103882 obstruction_interval: 540.0 direction_azimuth: -42.67951583862305 direction_elevation: 64.61225128173828 is_snr_above_noise_floor: True 9
  • 10. Reported Capacity & Latency 10
  • 11. Reported Capacity & Latency 11
  • 12. Reported Capacity & Latency • This is going to present some interesting issues for conventional TCP • TCP uses ACK pacing which means it attempts to optimize its sending rate over multiple RTT intervals • The variation in latency and capacity occurs at high frequency, which means that TCP control is going to struggle to optimise 12
  • 13. How well does all this work? Speedtest measurements: We should be able to get ~120Mbps out of a starlink connection. Right? 13
  • 16. TCP Flow Control Algorithms “Ideal” Flow behaviour for each protocol 16
  • 17. iperf3 – cubic, 60 seconds CUBIC Loss 17
  • 18. Qperf – quic (with cubic) QUIC/CUBIC Loss 18
  • 21. Protocol Considerations • Starlink services have two issues for transport protocols: • Very high jitter rates • High levels of micro-loss • Loss-based flow control algorithms will over-react and pull back the sending rate • Short transactions work well • Paced connections (voice, zoom) tend to work well most of the time • Bulk data transfer not so much • It’s better to use a conventional TCP control with a large SACK window or use loss-insensitive flow control algorithms, such as BBR, to get high transfer rate performance out of this service 21