< draft-lhan-problems-requirements-satellite-net-01.txt   draft-lhan-problems-requirements-satellite-net-02.txt >
Network Working Group L. Han, Ed. Network Working Group L. Han, Ed.
Internet-Draft R. Li Internet-Draft R. Li
Intended status: Informational Futurewei Technologies, Inc. Intended status: Informational A. Retana
Expires: 22 April 2022 19 October 2021 Expires: 17 August 2022 Futurewei Technologies, Inc.
M. Chen
L. Su
China Mobile
N. Wang
University of Surrey
13 February 2022
Problems and Requirements of Satellite Constellation for Internet Problems and Requirements of Satellite Constellation for Internet
draft-lhan-problems-requirements-satellite-net-01 draft-lhan-problems-requirements-satellite-net-02
Abstract Abstract
This document presents the detailed analysis about the problems and This document presents the detailed analysis about the problems and
requirements of satellite constellation used for Internet. It starts requirements of satellite constellation used for Internet. It starts
from the satellite orbit basics, coverage calculation, then it from the satellite orbit basics, coverage calculation, then it
estimates the time constraints for the communications between estimates the time constraints for the communications between
satellite and ground-station, also between satellites. How to use satellite and ground-station, also between satellites. How to use
satellite constellation for Internet is discussed in detail including satellite constellation for Internet is discussed in detail including
the satellite relay and satellite networking. The problems and the satellite relay and satellite networking. The problems and
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This Internet-Draft will expire on 22 April 2022. This Internet-Draft will expire on 17 August 2022.
Copyright Notice Copyright Notice
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Basics of Satellite Constellation . . . . . . . . . . . . . . 6 4. Basics of Satellite Constellation . . . . . . . . . . . . . . 6
4.1. Satellite Orbit . . . . . . . . . . . . . . . . . . . . . 6 4.1. Satellite Orbit . . . . . . . . . . . . . . . . . . . . . 6
4.2. Coverage of LEO and VLEO Satellites and Minimum Number 4.2. Coverage of LEO and VLEO Satellites and Minimum Number
Required . . . . . . . . . . . . . . . . . . . . . . . . 6 Required . . . . . . . . . . . . . . . . . . . . . . . . 6
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5.2. Dynamic Inter-satellite Communication . . . . . . . . . . 12 5.2. Dynamic Inter-satellite Communication . . . . . . . . . . 12
5.2.1. Inter-satellite Communication Overview . . . . . . . 12 5.2.1. Inter-satellite Communication Overview . . . . . . . 12
5.2.2. Satellites on Adjacent Orbit Planes with Same 5.2.2. Satellites on Adjacent Orbit Planes with Same
Altitude . . . . . . . . . . . . . . . . . . . . . . 15 Altitude . . . . . . . . . . . . . . . . . . . . . . 15
5.2.3. Satellites on Adjacent Orbit Planes with Different 5.2.3. Satellites on Adjacent Orbit Planes with Different
Altitude . . . . . . . . . . . . . . . . . . . . . . 17 Altitude . . . . . . . . . . . . . . . . . . . . . . 17
6. Use Satellite Network for Internet . . . . . . . . . . . . . 19 6. Use Satellite Network for Internet . . . . . . . . . . . . . 19
7. Problems and Requirements for Satellite Constellation for 7. Problems and Requirements for Satellite Constellation for
Internet . . . . . . . . . . . . . . . . . . . . . . . . 22 Internet . . . . . . . . . . . . . . . . . . . . . . . . 22
7.1. Common Problems and Requirements . . . . . . . . . . . . 22 7.1. Common Problems and Requirements . . . . . . . . . . . . 22
7.2. Satellite Relay . . . . . . . . . . . . . . . . . . . . . 24 7.2. Satellite Relay . . . . . . . . . . . . . . . . . . . . . 25
7.2.1. One Satellite Relay . . . . . . . . . . . . . . . . . 24 7.2.1. One Satellite Relay . . . . . . . . . . . . . . . . . 25
7.2.2. Multiple Satellite Relay . . . . . . . . . . . . . . 26 7.2.2. Multiple Satellite Relay . . . . . . . . . . . . . . 26
7.3. Satellite Networking . . . . . . . . . . . . . . . . . . 27 7.3. Satellite Networking . . . . . . . . . . . . . . . . . . 28
7.3.1. L2 or L3 network . . . . . . . . . . . . . . . . . . 27 7.3.1. L2 or L3 network . . . . . . . . . . . . . . . . . . 28
7.3.2. Inter-satellite-Link Lifetime . . . . . . . . . . . . 28 7.3.2. Inter-satellite-Link Lifetime . . . . . . . . . . . . 28
7.3.3. Problems for Traditional Routing Technologies . . . . 28 7.3.3. Problems for Traditional Routing Technologies . . . . 29
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 32 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 33
9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 32 9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 33
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 32 10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 33
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 32 11. References . . . . . . . . . . . . . . . . . . . . . . . . . 33
11.1. Normative References . . . . . . . . . . . . . . . . . . 32 11.1. Normative References . . . . . . . . . . . . . . . . . . 33
11.2. Informative References . . . . . . . . . . . . . . . . . 33 11.2. Informative References . . . . . . . . . . . . . . . . . 34
Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 35 Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 36
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 35 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 36
1. Introduction 1. Introduction
Satellite constellation for Internet is emerging. Even there is no Satellite constellation for Internet is emerging. Even there is no
constellation network established completely yet at the time of the constellation network established completely yet at the time of the
publishing of the draft (June 2021), some basic internet service has publishing of the draft (June 2021), some basic internet service has
been provided and has demonstrated competitive quality to traditional been provided and has demonstrated competitive quality to traditional
broadband service. broadband service.
This memo will analyze the challenges for satellite network used in This memo will analyze the challenges for satellite network used in
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(Figure 11). (Figure 11).
3. The local network access Internet through satellite relay 3. The local network access Internet through satellite relay
(Figure 12 for one satellite relay, Figure 13 for multiple (Figure 12 for one satellite relay, Figure 13 for multiple
satellite relay). satellite relay).
4. The local network access Internet through inter-satellite- 4. The local network access Internet through inter-satellite-
networking networking
(Figure 14). (Figure 14).
5. The End user terminal or local network access Internet through
satellite network and Mobile Access Network, From mobile access
network to satellite network or From satellite network to mobile
access network, Satellite network includes inter satellite network
and relay network
(Figure 15 for mobile access network to satellite network,
Figure 16 for satellite netowk to mobile access network).
S1----\ /-----------\ S1----\ /-----------\
/ \ / \ / \ / \
T---GW--GS1--S2--GS2-------PE Internet + T---GW--GS1--S2--GS2-------PE Internet +
\ / \ / \ / \ /
\---S3/ \-----------/ \---S3/ \-----------/
Figure 9: End user terminal access Internet through one satellite Figure 9: End user terminal access Internet through one satellite
relay relay
S1----\ S4----\ /-----------\ S1----\ S4----\ /-----------\
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/-----------\ S1-----S2-----S3---\ /------\ /-----------\ S1-----S2-----S3---\ /------\
/ \ / \ / \ / \ / \ / \
+ Local network CE------GS1--S4----S5---S6---GS2-------PE Internet+ + Local network CE------GS1--S4----S5---S6---GS2-------PE Internet+
\ / \ / \ / \ / \ / \ /
\-----------/ \---S7----S8----S9/ \------/ \-----------/ \---S7----S8----S9/ \------/
Figure 14: Local network access Internet through inter-satellite- Figure 14: Local network access Internet through inter-satellite-
networking networking
In above Figure 9 to Figure 14, the meaning of symbols are as +--------------+ +-------------+ +---------+ +--------+
| T or | |Mobile Access| |Satellite| |Internet|
| Local network+----+ Network +----+ Network +----+ |
+--------------+ +-------------+ +---------+ +--------+
Figure 15: End user terminal or local network access Internet
through Mobile Access Network and Satellite Network
+--------------+ +---------+ +-------------+ +--------+
| T or | |Satellite| |Mobile Access| |Internet|
| Local network+---+ Network +---+ Network +---+ |
+--------------+ +---------+ +-------------+ +--------+
Figure 16: End user terminal or local network access Internet
through Satellite Network and Mobile Access Network
In above Figure 9 to Figure 16, the meaning of symbols are as
follows: follows:
T The end user terminal T The end user terminal
GW Gateway router GW Gateway router
GS1, GS2, GS3 Ground station with L2/L3 routing/switch GS1, GS2, GS3 Ground station with L2/L3 routing/switch
functionality. functionality.
S1 to S9 Satellites S1 to S9 Satellites
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From the examples shown in Table 4 to Table 7, we can see that the From the examples shown in Table 4 to Table 7, we can see that the
lifetime of inter-satellite communication for the different group of lifetime of inter-satellite communication for the different group of
orbit planes are from couple of hundred seconds to about 18 hours. orbit planes are from couple of hundred seconds to about 18 hours.
This fact will impact the routing technologies used for satellite This fact will impact the routing technologies used for satellite
network and will be discussed in Section 7.3.3. network and will be discussed in Section 7.3.3.
7.3.3. Problems for Traditional Routing Technologies 7.3.3. Problems for Traditional Routing Technologies
When the satellite network is integrated with Internet by traditional When the satellite network is integrated with Internet by traditional
routing technologies, following provisioning and configuration (see routing technologies, following provisioning and configuration (see
Figure 15) will apply: Figure 17) will apply:
1. The ground stations connected to local network and internet are 1. The ground stations connected to local network and internet are
treated as PE router for satellite network (called PE_GS1 and treated as PE router for satellite network (called PE_GS1 and
PE_GS2 in the following context), and all satellites are treated PE_GS2 in the following context), and all satellites are treated
as P router. as P router.
2. All satellites in the network and ground stations are configured 2. All satellites in the network and ground stations are configured
to run IGP. to run IGP.
3. The eBGP is configured between PE_GS and its peered network's PE 3. The eBGP is configured between PE_GS and its peered network's PE
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* The local network routes are redistributed from IGP to eBGP * The local network routes are redistributed from IGP to eBGP
running on PE_GS2, and eBGP will advertise them to Internet. running on PE_GS2, and eBGP will advertise them to Internet.
/--------\ S1---S2----S3----\ /------\ /--------\ S1---S2----S3----\ /------\
/ \ / IGP domain \ / \ / \ / IGP domain \ / \
+ Local net CE--eBGP--PE_GS1---S4---S5---PE_GS2--eBGP--PE Internet + + Local net CE--eBGP--PE_GS1---S4---S5---PE_GS2--eBGP--PE Internet +
\ / \ / \ / \ / \ / \ /
\--------/ \---S6---S7---S8/ \------/ \--------/ \---S6---S7---S8/ \------/
Figure 15: Local access Internet through inter-satellite-networking Figure 17: Local access Internet through inter-satellite-networking
Local access Internet through inter-satellite-networking Local access Internet through inter-satellite-networking
On PE-GS1, due to the fact that IGP link between PE_GS1 and satellite On PE-GS1, due to the fact that IGP link between PE_GS1 and satellite
is not steady; this will lead to following routing activity: is not steady; this will lead to following routing activity:
1. When one satellite is connecting with PE_GS1, the satellite and 1. When one satellite is connecting with PE_GS1, the satellite and
PE_GS1 form a IGP adjacency. IGP starts to exchange the link PE_GS1 form a IGP adjacency. IGP starts to exchange the link
state update. state update.
skipping to change at line 1619 skipping to change at page 37, line 11
United States of America United States of America
Email: lhan@futurewei.com Email: lhan@futurewei.com
Richard Li Richard Li
Futurewei Technologies, Inc. Futurewei Technologies, Inc.
2330 Central Expy 2330 Central Expy
Santa Clara, CA 95050, Santa Clara, CA 95050,
United States of America United States of America
Email: rli@futurewei.com Email: rli@futurewei.com
Alvaro Retana
Futurewei Technologies, Inc.
2330 Central Expy
Santa Clara, CA 95050,
United States of America
Email: alvaro.retana@futurewei.com
Meiling Chen
China Mobile
32, Xuanwumen West
BeiJing 100053
China
Email: chenmeiling@chinamobile.com
Li Su
China Mobile
32, Xuanwumen West
BeiJing 100053
China
Email: suli@chinamobile.com
Ning Wang
University of Surrey
Guildford
Surrey, GU2 7XH
United Kingdom
Email: n.wang@surrey.ac.uk
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