ETSI TS 102 460 V1.2.1 (2015-12)

Satellite Earth Stations and Systems (SES); Broadband Satellite Multimedia (BSM); Address Management at the SI-SAP

RTS/SES-00354

General Information

• Status: Published
• Publication Date: 17-Dec-2015
• Technical Committee: SES SCN - Satellite Communications and Navigation
• Current Stage: 12 - Completion
• Due Date: 20-Dec-2015
• Completion Date: 18-Dec-2015

Standards Content (Sample)

TECHNICAL SPECIFICATION
Satellite Earth Stations and Systems (SES);
Broadband Satellite Multimedia (BSM);
Address Management at the SI-SAP

2 ETSI TS 102 460 V1.2.1 (2015-12)

Reference
RTS/SES-00354
Keywords
broadband, interworking, IP, management,
satellite
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3 ETSI TS 102 460 V1.2.1 (2015-12)
Contents
Intellectual Property Rights . 5
Foreword . 5
Modal verbs terminology . 5
Introduction . 5
1 Scope . 6
2 References . 6
2.1 Normative references . 6
2.2 Informative references . 7
3 Definitions and abbreviations . 7
3.1 Definitions . 7
3.2 Abbreviations . 9
4 Scenarios and service requirements. 11
4.0 Introduction . 11
4.1 Address Management (AM) . 11
4.2 Address Management functions . 12
4.2.1 IP layer Address Management functions . 12
4.2.2 BSM_IDs . 13
4.2.3 Access network scenarios . 13
4.3 Service requirements . 14
5 Unicast architecture requirements . 14
5.1 General requirements . 14
5.2 Management of BSM_IDs in an NCC . 15
5.3 Relating BSM_IDs to a BSM Network . 15
5.4 BSM Address Resolution (B-AR) . 16
5.5 BSM Reverse Address Resolution (B-RAR) . 18
5.6 BSM Dynamic ST Port Configuration (B-DSPC) . 18
5.7 Network Address Translation (NAT) . 19
Annex A (informative): Internet access scenarios . 21
A.0 Overview . 21
A.1 Unicast access services . 21
A.2 Routed IP access mode . 22
A.2.1 Service architecture . 22
A.2.2 Service characteristics . 22
A.2.3 Service protocol stack . 23
A.2.4 Customer Premises configurations for Internet Access . 23
A.2.4.1 Multi-computers LAN with its own internal private IP addressing . 23
A.3 Bridged access mode . 24
A.3.1 Service characteristics . 24
A.3.2 Service protocol stacks . 24
A.3.3 Hub configuration. 25
A.3.3.0 Introduction. 25
A.3.3.1 PPP Terminated Aggregation (PTA) model . 25
A.3.3.2 L2TP Access Aggregation (LAA) mode . 25
A.4 PPP router mode . 25
A.5 DHCP router mode . 26
A.5.1 Service presentation . 26
A.5.2 Service characteristics . 26
A.5.3 Service protocol stacks . 26
ETSI
4 ETSI TS 102 460 V1.2.1 (2015-12)
Annex B (informative): Address Management network topology . 28
B.1 Address Management SI-SAP model . 28
B.2 BSM network models . 29
Annex C (informative): Example of a double NAT network topology . 31
C.1 Double NAT network scenario . 31
C.2 Premises network routing . 32
C.2.0 Introduction . 32
C.2.1 Public Routable Networks . 32
C.2.2 Private Non-Routable Network . 32
C.3 Double NAT'ing Requirements . 32
Annex D (informative): RSM-B IP routing . 33
D.1 RSM-B overview . 33
D.2 RSM-B routing . 34
D.3 IP routing and address resolution function . 34
D.4 Default route . 36
Annex E (normative): RSM-A Address Resolution . 37
E.1 Introduction . 37
E.1.0 AR functionalities. 37
E.1.1 AR for customer networks. 37
E.1.1.1 AR at Terrestrial Interface for customer networks . 37
E.1.1.2 AR at Satellite Interface for customer networks . 37
E.1.1.3 Satellite ARP Description . 38
E.2 State diagram . 39
E.3 Procedures . 40
Annex F (normative): Specification of SI-SAP AR Primitives . 41
F.1 C-Plane AR Primitives . 41
F.2 Primitives . 41
F.2.1 SI-C-AR_QUERY . 41
F.2.2 SI-C-AR_INFO . 41
F.3 Parameters . 42
F.3.1 AR query handle . 42
F.3.2 AR info handle . 42
F.3.3 AR info type . 42
F.3.4 Network address . 42
F.3.5 Network address type . 42
F.3.6 Status . 43
F.3.7 BSM_ID . 43
F.3.8 BSM multicast flag . 43
Annex G (informative): Examples of AR function usage . 44
G.1 Suggestion for data stored in AR caches . 44
G.2 SI-C-AR_INFO Function . 44
G.3 SI-C-AR_QUERY . 45
History . 46

ETSI
5 ETSI TS 102 460 V1.2.1 (2015-12)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (http://ipr.etsi.org).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This Technical Specification (TS) has been produced by ETSI Technical Committee Satellite Earth Stations and
Systems (SES).
Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
Introduction
The present document defines scenarios and architectures to provide address management functions for a BSM
network.
ETSI
6 ETSI TS 102 460 V1.2.1 (2015-12)
1 Scope
The present document concerns the address management functions that are required to support interworking of a BSM
network with an IP network, including use as part of the general Internet, in particular the address management
functions related to the BSM SI-SAP.
The SI-SAP is described in the BSM functional architecture [1] and defined in the SI-SAP specification [3]. A key
element in the present document is the BSM_Identifier (BSM_ID) which is the SI-SAP address that identifies a BSM
subnetwork point of attachment (SNPA). A BSM network uses the BSM_ID when sending and receiving data via the
SI-SAP: the BSM_ID is an abstraction of the lower layer address that would otherwise be used.
The present document describes the relationships between IP Addresses and BSM_IDs and also describes how to create,
manage, and query the BSM_IDs for the purpose of sending and receiving user data (in particular IP packets) via the
SI-SAP.
NOTE 1: In some systems, requesting to pass traffic across the network also causes reservation of bandwidth. This
is to be considered out of scope of the present recommendation, but assumptions that a notification (e.g.,
bandwidth allocation) will be sent by a QoS Manager will be made.
The present document divides into two parts:
• address management scenarios and architectures;
• unicast address resolution at the SI-SAP.
Lower layer address management (i.e. management of addresses below the SI-SAP) is beyond the scope of the present
document.
NOTE 2: Examples of lower layer addresses that are out-of-scope include Data Link layer addresses, MAC layer
addresses and Physical layer addresses.
The present document elaborates the details of the address management functions, notably the address resolution
function, as defined in the SI-SAP specification ETSI TS 102 357 [3]. It also builds on several other reports:
• ETSI TR 101 984 [i.1];
• ETSI TR 101 985 [i.2];
• ETSI TR 102 155 [i.7].
2 References
2.1 Normative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
reference document (including any amendments) applies.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
The following referenced documents are necessary for the application of the present document.
[1] ETSI TS 102 292: "Satellite Earth Stations and Systems (SES); Broadband Satellite Multimedia
(BSM) services and architectures; Functional architecture for IP interworking with BSM
networks".
ETSI
7 ETSI TS 102 460 V1.2.1 (2015-12) ®
[2] IEEE 802 (2001): "IEEE Standard for Local and Metropolitan Area Networks: Overview and
Architecture".
NOTE: Available at https://standards.ieee.org/about/get/802/802.html.
[3] ETSI TS 102 357 (V1.1.1): "Satellite Earth Stations and Systems (SES); Broadband Satellite
Multimedia (BSM); Common Air interface specification; Satellite Independent Service Access
Point SI-SAP".
2.2 Informative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
reference document (including any amendments) applies.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
The following referenced documents are not necessary for the application of the present document but they assist the
user with regard to a particular subject area.
[i.1] ETSI TR 101 984: "Satellite Earth Stations and Systems (SES); Broadband Satellite Multimedia
(BSM); Services and architectures".
[i.2] ETSI TR 101 985: "Satellite Earth Stations and Systems (SES); Broadband Satellite Multimedia;
IP over Satellite".
[i.3] ETSI TS 102 295: "Satellite Earth Stations and Systems (SES); Broadband Satellite Multimedia
(BSM) services and architectures; BSM Traffic Classes".
[i.4] ETSI TR 102 353: "Satellite Earth Stations and Systems (SES); Broadband Satellite Multimedia
(BSM); Guidelines for the Satellite Independent Service Access Point (SI-SAP)".
[i.5] IETF RFC 1112: "Host extensions for IP Multicasting".
[i.6] ETSI TR 102 157: "Satellite Earth Stations and Systems (SES); Broadband Satellite Multimedia;
IP Interworking over satellite; Performance, Availability and Quality of Service".
[i.7] ETSI TR 102 155: "Satellite Earth Stations and Systems (SES); Broadband Satellite Multimedia;
IP interworking over satellite; Addressing and routing".
[i.8] IETF RFC 3022: "Traditional IP Network Address Translator (Traditional NAT)".
[i.9] IETF RFC 826: "An Ethernet Address Resolution Protocol: or converting network protocol
addresses to 48.bit Ethernet address for transmission on Ethernet hardware".
[i.10] IETF RFC 2131: "Dynamic Host Configuration Protocol".
[i.11] IETF RFC 3046: "DHCP Relay Agent Information Option".
[i.12] IETF RFC 4861: "Neighbor Discovery for IP version 6 (IPv6)".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
Address Resolution (AR): provides a mechanism that associates L2 information with the IP address of a system
NOTE: Many L2 technologies employ unicast AR at the sender: an IP system wishing to send an IP packet
encapsulates it and places it into a L2 frame. It then identifies the appropriate L3 adjacency (e.g. next hop
router, end host) and determines the appropriate L2 adjacency (e.g. MAC address in Ethernet) to which
the frame should be sent so that the packet gets across the L2 link.
ETSI
8 ETSI TS 102 460 V1.2.1 (2015-12)
Address Resolution Protocol (ARP): protocol defined in IETF RFC 826 [i.9] that is used to associate network
protocol addresses to 48 bit Ethernet addresses for transmission on Ethernet hardware
BSM Address Resolution (B-AR): provides a mechanism that associates a BSM_ID with the IP address of a system
BSM Bearer service: transport service from one SI-SAP to one other SI-SAP (unicast service); or from one SI-SAP to
one or more SI-SAPs (multicast service); within the same BSM subnetwork
BSM Subnetwork: infrastructure that provides transport services between STs
NOTE: The boundary of the BSM subnetwork corresponds to the SI-SAP in those STs; hence the BSM
subnetwork includes elements of the STs, the Gateways and the Satellite.
BSM Network: one BSM subnetwork together with the necessary interworking functions that enable that BSM
subnetwork to interwork with one or more attached networks at the STs
BSM_Identity (BSM_ID): SI-SAP address that defines the BSM Subnetwork Point of Attachment (SNPA)
NOTE: The BSM_ID is divided into BSM Unicast IDs (BSM_UID) and BSM Group IDs (BSM_GID).
BSM Subnetwork Point of Attachment (B-SNPA): SI-SAP endpoint of the BSM data transport services
NOTE: The BSM_ID is used to address data sent to and received from the BSM Subnetwork Point of
Attachment.
dynamically assignable: may be reassigned during normal operations
dynamically assigned: assigned at a well-defined point in an operation, such as at log-in
forwarding: process of relaying an IP Packet from a source to a destination through intermediate network segments and
nodes
NOTE: The forwarding decision is based on information that is already available in the routing table. The
decision on how to construct that routing table is the routing decision - see below.
IP datagram (datagram): self-contained, independent entity of data that conforms to the IP protocol
IP Packet (Packet): IP packet is identical to an IP datagram
NOTE: An IP packet contains sufficient information to be routed from the source to the destination computer
without reliance on earlier exchanges between this source and destination computer and the transporting
network.
Network Access Provider (NAP): provides transmission resources to the Service Providers (SP) for accessing their
subscribers
Network Address Translation (NAT): process of mapping between a set of IP addresses in one IP network to/from
another set of IP addresses in another IP network
NOTE: NAT is defined in IETF RFC 3022 [i.8]. NAT is typically used to map between internal IP addresses and
officially assigned external addresses.
Private IP address: address assigned from one of the IETF defined private addressing blocks
Queue Identifier (QID): SI-SAP parameter that identifies an abstract queue at the SI-SAP
NOTE: The QID is used to identify a specific lower layer resource when sending (submitting) data via the
SI-SAP.
routing: process of selecting paths for packets to take based on a routing table
NOTE: The routing table can be created through different routing protocols, some of which include automatic
discovery.
Satellite Network Operator (SNO): owns and is responsible for maintaining, managing, deploying and operating the
Satellite Network (i.e. the BSM network) excluding terminals (STs and Hubs)
ETSI
9 ETSI TS 102 460 V1.2.1 (2015-12)
SI-SAP Instance (SAPI): specific independent instance of the SI-SAP in one ST
NOTE: A single unicast BSM_ID (UID) is associated with each instance of the SI-SAP (each SAPI). In addition,
one or more group BSM_IDs (GIDs) may be associated with each instance of the SI-SAP.
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
AAA Authorisation, Authentication, and Accounting
AAL5 ATM Adaption Layer 5
AM Address Management
API Application Protocol Interface
AR Address Resolution
ARP Address Resolution Protocol
ATM Asynchronous Transfer Mode
B-AR BSM Address Resolution
BAS Broadband Access Server
B-DSPC BSM Dynamic ST Port Configuration
BGP Border Gateway Protocol
BOOTP Bootstrap Protocol
BSM Broadband Satellite Multimedia
BSM_GID BSM Group Identity
BSM_ID BSM Identity
BSM_UID BSM Unicast Identity
C2P Connection Control Protocol
CHAP Challenge HAndshake Protocol
CPE Customer Premises Equipment
CPN Customer Premises Network
DHCP Dynamic Host Configuration Protocol
DSL Digital Subscriber Loop
DSPC Digital Signal Processing and Control
DVB-RCS Digital Video Broadcasting - Return Channel via Satellite
DVB-S Digital Video Broadcasting - Satellite
FLSS Forward Link SubSystem
GID Group ID
GW Gateway
GW/ST Gateway/ Satellite Terminal
IANA Internet Assigned Numbers Authority
ID IDentity
IP Internet Protocol
IPCP IP Control Protocol
IPoA IP over ATM
IPv4 Internet Protocol version 4
IPv6 Internet Protocol version 6
ISP Internet Service Providers
L2TP Layer 2 Tunnelling Protocol
LAA L2TP Access Aggregation
LAC L2TP Access Concentrator
LAN Local Area Network
LLC Logical Link Control
LNS L2TP Network Server
MAC Medium Access Control
MPE Multi-Protocol Encapsulation
MPEG Moving Picture Experts Group
MS Management Station
NAP Network Access Provider
NAPT Network Address and Port Translation
NAT Network Address Translation
NCC Network Control Centre
ND Neighbour Discovery
NHR Next Hop Router
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10 ETSI TS 102 460 V1.2.1 (2015-12)
NMC Network Management Centre
NOCC Network Operations Control Centre
OBP On-Board Processing
OSPF Open Shortest Path First
PAP Password Authentication Protocol
PC Premises Customer
PPP Point-to-Point Protocol
PPPoA PPP over ATM
PPPoE PPP over Ethernet
PPPoEoA PPP over Ethernet over ATM
PSTN Public Switched Telephone Network
PTA PPP Terminated Aggregation
PVC Permanent Virtual Channel
QID Queue Identifier
QoS Quality of Service
RADIUS Remote Access Dial-In User Service
RAR Reverse Address Resolution
RARP Reverse Address Resolution Protocol
RCST Return Channel Satellite Terminal
RIP Routing Information Protocol
RLSS Return Link SubSystem
RSCT DVB-RSC Terminal
RSGW Regenerative Satellite GateWay
RSM Regenerative Satellite Mesh
RSM-A Regenerative Satellite Mesh - A
RSM-B Regenerative Satellite Mesh - B
SAP Service Access Point
SAPI SI-SAP Instance
SCN Satellite Communication Network
SD Satellite Dependent
SDAF Satellite Dependent Adaptation Functions
SDU Service Data Unit
SI Satellite Independent
SIAF Satellite Independent Adaptation Functions
SI-SAP Satellite Independent Service Access Point
SLA ID Site-Level Aggregation IDentifier
SLA Service Level Agreement
SME Small and Medium Enterprise
SNHA Satellite Next Hop Address
SNMP Simple Network Management Protocol
SNO Satellite Network Operator
SNPA Subnetwork Point of Attachment
SOHO Small Office - Home Office
SP Service Provider
SPC ST Port Configuration
ST Satellite Terminal
ST/GW Satellite Terminal/ Gateway
TSS-A Transparent Satellite Star - A
UID Unicast ID
UP Upper Protocols
VC Virtual Channel
VPN Virtual Private Network
WAN Wide Area Network
ETSI
11 ETSI TS 102 460 V1.2.1 (2015-12)
4 Scenarios and service requirements
4.0 Introduction
The task of an ST is to forward IP packets over a BSM network to the next hop node as part of the process of
forwarding the IP packet to the final destination Host for which the IP packet is intended. There may be alternative
routes over the satellite network to provide link diversity or to increase the overall capacity of the satellite link.
The unicast scenario concerns a point-to-point link, either one-way or two way. The associated BSM Bearer Service
topology can be a mesh such that two STs exchange user data directly, or a star such that the user data passes via a
gateway.
Control and management information, corresponding to the C and M planes of the SI-SAP, would normally pass
through a Network Control Centre (NCC) even if the user data is passed directly between STs. Systems with distributed
control and management systems, i.e. where C and M plane data does not pass through the NCC, can be built but this
architecture is not considered further in the present document.
4.1 Address Management (AM)
By definition (see ETSI TR 102 155 [i.7]) a BSM network is designed to transport IP packets and provides, as a
minimum, the address management services required to support IP forwarding from a source BSM network node (or
ingress ST) to a destination BSM network node (or egress ST).
The present document focuses on unicast address management, but some of these functions may also be applicable to
multicast address management.
This clause specifies the IP address management services required in different scenarios. In a satellite network, IP
address management services are closely associated with resource management (see ETSI TR 102 155 [i.7]) and
excessive traffic over the satellite network should be avoided.
NOTE 1: In the context of the present document, address management does not include any routing functions and
IP routing protocols (e.g. RIP, OSPF, and BGP) are not considered further in the present document.
It is assumed that protocol layers are independent and thus layer 2 addresses may be managed independently of layer 3
addresses.
NOTE 2: Layer 2 addresses may be derived from the layer 3 addresses in some cases. For example,
IETF RFC 1112 [i.5] defines how layer 2 group addresses may be directly derived from Layer 3 multicast
addresses.
BSM Identity (BSM_ID) is a general term that includes both Unicast and Group Identities. Above the SI-SAP,
BSM_IDs are associated with IP (Layer 3) addresses and below the SI-SAP BSM_IDs are typically associated with
MAC (Layer 2) addresses. More specifically, the BSM Unicast ID (BSM_UID) is associated with Unicast addresses
while the BSM Group Identity (BSM_GID) is associated with multicast addresses.
As shown in figure 4.1, Address Management is used to coordinate the requirements for managing the addresses that
are used for transporting user data between the ISP/Customer, Network Access Provider and Satellite Operator.
ETSI
IP subnet C4
IP subnet C3
Ethernet/ Other
IP subnet C2
IP subnet C1
IP subnet B4
IP subnet B3
IP subnet B2
IP subnet B1
IP subnet A4
IP subnet A3
IP subnet A2
IP subnet A1 Ethernet/ Other
12 ETSI TS 102 460 V1.2.1 (2015-12)
IP LAYER
ISP &
customer
IP to IP associations (routing/ bridging tables)
SIAF: IP to BSM_ID association
BSM_IDBSM_IDss
network access
BSMBSM_ID_ID BSM_IDBSM_ID BSM_IDBSM_ID
provider
ssububnetnet 1 1 ssububnetnet 2 2 ssuubnebnet 3t 3
Map Map Map
subnet 1 subnet 2 subnet 3
SDAF: BSM_ID to MAC association
satellite network
SATELLITE DEPENDENT IDs (SDIDs)
operator
e.g. MAC_Add; PIDs; Channel_ID

Figure 4.1: BSM Address Management layers
4.2 Address Management functions
4.2.1 IP layer Address Management functions
Figure 4.2 shows the BSM network as the middle network of three concatenated IP networks (A, B, C). In this example,
the IP networks A and C are external local area networks or wide area networks, and the IP network B is the BSM
Network. The IP networks A and C could be the Internet, a corporate internet, corporate intranet, a SOHO network or
any enterprise network that needs to use the BSM network as an access network. Address Management will support
functions consistent with IP forwarding between IP networks A and C via the BSM network.
ST1 ST2
IP Interworking IP Interworking
Router or bridge Router or bridge
IP network A IP network B IP network C
with with
(LAN-WAN) (BSM) (LAN-WAN)
optional NAT optional NAT
SIAF SIAF
SI-SAP SI-SAP
SDAF SDAF
KEYKEY
IP fuIP funncctiotionn
AAddaappttaattiionon f fuunctnctiionon
SD SD
Satellite
SSDD f funcuncttiionon
function function
payload
LAN/ WAN BSM NETWORK LAN/ WAN
Figure 4.2: A BSM network and interworking with other IP networks
ETSI
13 ETSI TS 102 460 V1.2.1 (2015-12)
The present document considers two different cases of IP interworking within the ST:
a) ST/ Router: In this case, the ST interconnects the networks at the IP layer and routes IP packets between the
different attached networks.
b) ST/ Bridge: In this case, the ST interconnects the networks at the subnetwork interface level and forwards
frames between these interfaces.
NOTE: A bridge is independent of the higher layer protocol: i.e. transparent to the IP packets.
These different cases are described in more detail in annex A for the Access Network scenario.
Both customer facing and satellite facing interfaces can use either private IP addresses or globally unique IP addresses.
In general, the customer facing and satellite facing ports of a given ST will have different network address ranges and to
accommodate this, NAT may be required as part of the ST IP layer.
NAT can be used as part of the ST/Router case to translate between different address ranges. For example, NAT could
be used to allow IP network A and/or IP network C to operate with private addresses. As a second example, NAT can
allow IP network A and IP network C to have the same network addresses and may also be required because of a
customer's privacy requirements as illustrated in annex D. There are several potential problems when using NAT
(see for example the problems described in IETF RFC 3022 [i.8] and these problems may apply in the BSM network.
Thus the BSM Address Management IP layer services that may be required are:
• Address Resolution (AR): finding the next hop BSM_ID that is associated with a given next hop IP address;
• Reverse Address Resolution (RAR): finding the next hop IP address that is associated with a given next hop
BSM_ID;
• ST Port Configuration (SPC): providing some autoconfiguration of the ST satellite facing port;
• Network Address Translation (NAT): mapping of IP addresses within the ST.
The infrastructure needed to support these four AM services is addressed hereafter in the rest of the document.
4.2.2 BSM_IDs
The BSM_ID is an SI-SAP address that identifies the BSM subnetwork point of attachment (SNPA).
Each ST in the system will have one BSM_UID, associated with the SI-SAP. STs that provide a gateway function, and
the Hub ST in a star network, may have multiple SI-SAP instances and can therefore have one or more BSM_UIDs (one
per SI-SAP). In all cases, the BSM_UID will be associated with one IP address above the SI-SAP and with a MAC
address below the SI-SAP. Each SI-SAP may also be associated with zero or more BSM_GIDs.
The SI-SAP [3] specifies that the format for the BSM_ID shall be a 48 bit address (6 octets) that conforms to the
IEEE 802 [2] specification for LAN MAC addresses.
4.2.3 Access network scenarios
The present document is concerned with access network scenarios. In this case, a BSM network allows the user host
equipment to be directly connected to a ST or indirectly connected to a ST via a private LAN. The BSM network then
acts as an Access network to provide:
• Access to one or more Internet Service Providers (ISP) network, which in turn will provide access to the
Internet.
• Access to a Corporate Network (this includes linking sections of a corporate network).
Table 4.1 summarizes the types of services that can be offered based on unicast access.
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14 ETSI TS 102 460 V1.2.1 (2015-12)
Table 4.1: Types of services for consumers and SME/SOHO
Type of User Internet Access Corporate Access
Consumer and SOHO Any Internet based services Teleworking
Corporate Intranet access
Corporate Any Internet based services Central Office access
Corporate Intranet access
The network reference architecture is shown in figure A.1. It should be noted that the same network architecture
supports connections to both ISP and Corporate Networks. The central element of this architecture is an Access Router
or Broadband Access Server (BAS) which interconnects the Hub with external networks. The Satellite Network
provides the following access services:
• IP Routing architectures:
- Routed IP mode.
- PPPoA router mode.
- DHCP router mode.
• IP Bridging architectures:
- Bridged mode.
See annex A for detailed examples illustrating this topic.
4.3 Service requirements
It is assumed that:
1) an ST has at least two IP addresses, one facing the customer network and one used in the BSM Network;
2) these IP addresses (i.e. both the customer facing IP address and the satellite IP address) can be either private IP
addresses or globally unique IP addresses;
3) the ST satellite IP address shall be unique within the BSM network;
4) the IP addresses of the ST can be static and fixed through an ST internal configuration or dynamic and
allocated when the ST starts;
5) NAT may be used in the ST, gateway or both.
5 Unicast architecture requirements
5.1 General requirements
A common architecture is essential for all BSM STs (see ETSI TR 102 157 [i.6]) in order to ensure their
interoperability. This architecture shall support the AM services discussed in clause 4. The address management
functional architecture shall conform to both the BSM functional architecture [1] and the SI-SAP specification [3].
The architecture requirements include:
• the need for AM services to function by passing Address Management Primitives across the SI-SAP, thus
forming an API, and messages between the BSM client and server as defined in the BSM architecture [1];
• the use of a client server architecture to provide scalability and integration into existing management
structures;
• the need to interwork with IP functions dealing with address management at or below the network layer; this
will ensure that the BSM function will evolve with IP protocols;
ETSI
15 ETSI TS 102 460 V1.2.1 (2015-12)
• the need to minimize the address management related traffic over the satellite link to avoid wasting satellite
resources and the effects of the satellite link delay.
The unicast AM services should support all types of unicast IP packet forwarding:
• Host via ST, via BSM Network, to host via gateway.
• Host via ST, via BSM Network, to host via ST.
• Host via gateway, via BSM Network, to host via ST.
In addition, some distributed AM services may be required. To support this, the architecture should support the
following elements:
• storage of AR tables (i.e. next-hop neighbour AR caches) at each ST;
• transfer of AR tables between the AR Server and the AR Clients;
• optional NAT at each ST (this includes both user/access STs and gateway STs).
5.2 Management of BSM_IDs in an NCC
The management of BSM_IDs involves at least two parties, a Satellite Network Operator (SNO) and a Network Access
Provider (NAP) as defined in the BSM Services and Architectures (see ETSI TR 101 984 [i.1]). An SNO owns and is
responsible for maintaining, managing, deploying and operating the BSM network excluding STs and gateways. A NAP
provides transmission resources to the Service Providers (SP) for accessing their subscribers.
Adopting this model, the following rules apply:
1) The SNO shall have responsibility for BSM_ID management over the entire BSM Network and shall therefore
set the policy for allocation of BSM_IDs. In particular, the SNO shall be responsible for ensuring that the
uniqueness rule is met.
2) The NAP shall be responsible for BSM_ID management over its subset of the BSM Network. The NAP shall
allocate individual BSM_IDs to STs and shall also define the rules for managing the associated satellite
network IP addresses.
5.3 Relating BSM_IDs to a BSM Network
Some address management functions could be implemented above, below or both above and below the SI-SAP. For
reference, the BSM protocol stack, reproduced from ETSI TS 102 295 [i.3], is shown in figure 5.1. Address Resolution
primitives pas
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