SIST ETS 300 458 E1:2003

• Abstract:

  To define the network internal interface for provision of the ISDN fram relay bearer service. The implementation alternative for and the exact location of the interface are to be defined.

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 33.080 - Integrated Services Digital Network (ISDN)
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2003
• Due Date: 01-Dec-2003
• Completion Date: 01-Dec-2003
• Ref Project: ETSI ETS 300 458 ed.1 (1995-10) - Integrated Services Digital Network (ISDN); Specification of the Remote Frame Handler Interface (RFHI)

SIST ETS 300 458 E1:2003 is the Slovenian standard identical to ETS 300 458 Edition 1, published by SIST. It specifies the manufacturer-independent Remote Frame Handler Interface (RFHI) for the Integrated Services Digital Network (ISDN), between the local Connection Related Function (CRF) and the Remote Frame Handler (RFH). In practice, it tells network and equipment designers how frame relay bearer service is accessed, signalled, and administered at that interface.

What does SIST ETS 300 458 E1:2003 specify?

SIST ETS 300 458 E1:2003 specifies the RFHI for ISDN frame mode services, with the RFH treated as remote to the local CRF and accessed through a two-step frame mode call establishment. It supports case A services only, and it allows the RFHI to be used as a network-internal interface, an inter-network interface, or a private-public network interface.

The document focuses on the interface itself and the additional requirements that arise directly from standardizing that interface. It does not define the frame relay services themselves, and it leaves open alternative implementations of a network-internal interface for Frame Relay Bearer Service (FRBS).

The document is organized into these main clauses and annexes:

Clause / annex	What it covers
Clause 1	Scope and applicability
Clause 2	Normative references
Clause 3	Definitions, symbols and abbreviations
Clause 4	Reference configuration and functional model
Clause 5	Access methods supported by the RFHI specification
Clause 6	Numbering, addressing and terminal selection
Clause 7	Interface structure
Clause 8	OA&M
Clause 9	RFHI signalling
Annex A	Requirements on common channel signalling system
Annex B	Bibliography

The combination of the RFHI with the Packet Handler access point Interface (PHI) is outside the scope. The document also states that only the access methods in this ETS are covered, while a subset may be offered in a given implementation.

What are the key requirements of SIST ETS 300 458 E1:2003?

SIST ETS 300 458 E1:2003 ties the RFHI to specific ISDN access methods, channel structures, numbering rules, and signalling behavior. For implementers, the important point is that the RFH and the CRF-F must behave consistently enough that subscribers see the same service whether access is local or remote.

Access methods and service behavior

Clause 5 says the RFHI supports case A access methods to the frame relay services defined elsewhere, and that the subscriber shall see identical services and use the same Q.933 signalling procedures whether the RFHI is local or remote. This matters because the network design can change behind the interface, but the subscriber-facing call behavior must stay the same.

Clause 5 also defines two physical access families:

• access via B-channel, with a transparent 64 kbit/s connection
• access via multiple-rate channel, with a transparent n x 64 kbit/s connection

Each of those can be permanent or on-demand at Layer 1. Permanent Layer 1 means the path is established at subscription time and maintained, while on-demand uses Q.931 procedures as modified by ETS 300 403-1. In practice, that tells the designer whether the access is fixed or call-controlled.

Numbering and terminal selection

Clause 6 uses the ISDN numbering plan for on-demand access connections. The calling and called party number, and optionally the subaddress, identify the TE and the RFH over the RFHI. For terminal selection and compatibility checking, the incoming call must carry the called subaddress and the low layer capability.

This matters because the RFHI has to support call setup decisions that depend on identity and compatibility, not only on the physical channel. Where switched frame mode connections are concerned, numbering and addressing follow Q.933 instead.

Interface structure and channels

Clause 7 states that the RFHI consists of one or more ISDN Primary Rate Accesses (PRAs) for B-channels and n x 64-channels, and that the RFH assumes the user side. The D64-channel is reserved for circuit mode signalling that controls the B-channels and n x 64-channels, while the B-channel and n x 64-channel carry in-channel frame mode signalling and frame transmission.

For permanent Layer 1 access only, no D64-channel signalling is required and a 30 channel Pulse Code Modulation (PCM 30) system may be used instead of a PRA. That is a practical implementation choice: if there is no on-demand control on the access, the signalling channel is not needed in the same way.

OA&M and administration

Clause 8 limits Operations, Administration and Maintenance (OA&M) to the RFHI-related parts that need coordination between CRF-F/S and RFH. The document says these requirements should be kept to a minimum, aligned with PRA OA&M where possible, and supported as separate administrative procedures on each side, with consistency ensured externally.

For administration, the RFHI is treated much like a PABX with PRAs. For operations and maintenance, the document points back to the PRA physical layer, data link layer, and network layer specifications. Accounting for connections over the RFHI is performed by the access network and/or the RFH.

Signalling rules

Clause 9 sets the RFHI-specific Layer 3 rules on the D64-channel and says signalling is based on normal Q.931 procedures, with some option reductions. The RFH always assumes the user side, the CRF-F the network side, and the RFH is responsible for time slot allocation on the PRA.

For outgoing calls from CRF-F to RFH, the SETUP shall include a calling party number with an allowed screening indicator, the channel indication "channel is indicated, no acceptable alternative" is not allowed, and the RFH shall accept a bearer capability coded as in Q.933. For incoming calls from RFH to CRF-F, the SETUP shall include the Called Party Number, and the same channel indication restriction applies. For call clearing, the cause location is set to user, and RFH congestion may be reported with cause 42.

What terms does SIST ETS 300 458 E1:2003 define?

SIST ETS 300 458 E1:2003 defines the main interface roles and access situations used throughout the document. These terms matter because they separate the subscriber side, the RFH side, and the interface itself.

• access channel - The channel used to reach the RFH, either 64 kbit/s or n x 64 kbit/s.
• access network - The set of ISDN CRFs that connect the subscriber to the RFH.
• CRF-F - The CRF physically connected to the RFH.
• CRF-S - The CRF to which subscribers are connected, also called the local CRF.
• local RFHI access - The configuration where CRF-F and CRF-S are the same entity.
• remote RFHI access - The configuration where CRF-F and CRF-S are separate entities.
• RFHI OA&M - The OA&M aspects that require coordination between the CRF-F/S side and the RFH side.
• outgoing call / incoming call - The call direction from CRF-S to RFH, or from RFH to CRF-F.

Who uses SIST ETS 300 458 E1:2003?

SIST ETS 300 458 E1:2003 is used by organizations that design, implement, and operate ISDN frame relay access. It is relevant wherever the RFH may belong to the ISDN itself, to another network, or to a private-public network interface.

In practice, the standard is used by:

• network equipment manufacturers defining RFHI behavior
• ISDN network designers and integrators planning CRF-F and RFH interworking
• access network operators configuring PRAs, numbering, and call setup
• operations and maintenance teams managing RFHI-related administration
• buyers or specifiers checking whether a proposed ISDN frame relay interface matches the RFHI model

Which standards are used with SIST ETS 300 458 E1:2003?

SIST ETS 300 458 E1:2003 depends on a set of numbered references for numbering, signalling, PRA structure, supplementary services, and frame relay behavior. The table below shows what each reference contributes.

Reference	What it contributes
CCITT Recommendation E.164	ISDN numbering plan
CCITT Recommendation E.165	Timetable for numbering plan implementation
CCITT Recommendation I.324	ISDN network architecture and local CRF concept
CCITT Recommendation Q.933	DSS1 signalling for Frame Mode Bearer Service
ETS 300 011	Primary rate user-network interface, Layer 1 specification and test principles
ETS 300 089	Calling Line Identification Presentation (CLIP) service description
ETS 300 090	Calling Line Identification Restriction (CLIR) service description
ETS 300 099	Packet Handler access point Interface (PHI)
ETS 300 399-1	General description of frame relay services
ETS 300 399-2	ISDN frame relay bearer service definition
ETS 300 402-1	DSS1 data link layer, general aspects
ETS 300 402-2	DSS1 data link layer application protocol specification
ETS 300 403-1	DSS1 layer 3 basic call control, protocol specification
ETS 300 403-2	DSS1 layer 3 basic call control, SDL diagrams

What does the SIST ETS 300 458 E1:2003 document contain?

SIST ETS 300 458 E1:2003 contains the RFHI scope, definitions, reference configurations, access methods, numbering rules, interface structure, OA&M rules, and signalling requirements. It also includes figures that show the RFHI as a network-internal interface, an inter-network interface, and at the T reference point, plus a functional model and protocol stack view.

The document is useful for interface design because it identifies the roles of CRF-S, CRF-F, and RFH, and shows how DSS1, SS7, frame mode signalling, and frame transmission fit together. It is also useful for testing and acceptance because Clause 9 gives the required call setup and clearing behavior on the D64-channel.

Annex A summarizes the common channel signalling system requirements derived from the user-network interface, including the bearer service, bearer type, and supplementary services that affect the connection. Annex B gives background references for further study.

SLOVENSKI STANDARD
01-december-2003
Digitalno omrežje z integriranimi storitvami (ISDN) – Specifikacija vmesnika
oddaljenega blokovnega strežnika (RFHI)
Integrated Services Digital Network (ISDN); Specification of the Remote Frame Handler
Interface (RFHI)
Ta slovenski standard je istoveten z: ETS 300 458 Edition 1
ICS:
33.080 Digitalno omrežje z Integrated Services Digital
integriranimi storitvami Network (ISDN)
(ISDN)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN ETS 300 458
TELECOMMUNICATION October 1995
STANDARD
Source: ETSI TC-NA Reference: DE/NA-023212
ICS: 621.395
ISDN, interface
Key words:
Integrated Services Digital Network (ISDN);
Specification of the Remote Frame Handler Interface (RFHI)
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
F-06921 Sophia Antipolis CEDEX - FRANCE
Postal address:
650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
Office address:
c=fr, a=atlas, p=etsi, s=secretariat - [e-mail]
X.400: Internet:
Tel.: [phone] - Fax: [phone]
Copyright Notification: No part may be reproduced except as authorized by written permission. The copyright and the
foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 1995. All rights reserved.
New presentation - see History box

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ETS 300 458: October 1995
Whilst every care has been taken in the preparation and publication of this document, errors in content,
typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to
"ETSI Editing and Committee Support Dept." at the address shown on the title page.

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ETS 300 458: October 1995
Contents
Foreword .5
1 Scope .7
2 Normative references.8
3 Definitions, symbols and abbreviations.9
3.1 Definitions .9
3.2 Abbreviations .9
4 Reference configuration and functional model.10
4.1 RFHI applications.10
4.1.1 RFHI as network-internal interface.10
4.1.2 RFHI as inter-network interface .10
4.1.3 RFHI at T reference point.11
4.2 Reference configuration.11
4.2.1 Network configuration.11
4.2.2 Access network configuration .11
4.3 Functional model.13
5 Access methods supported by the RFHI specification.14
5.1 Services and access methods.14
5.2 Access via B-channel.14
5.2.1 Layer 1 permanent .14
5.2.2 Layer 1 on-demand .14
5.3 Access via multiple-rate channel .14
5.3.1 Permanent layer 1 .14
5.3.2 On-demand layer 1.15
6 Numbering, addressing and terminal selection.15
6.1 Numbering and addressing.15
6.2 Terminal selection and compatibility checking.15
7 Interface structure .15
7.1 General .15
7.2 RFHI channel types .15
7.2.1 D64-channel .16
7.2.2 B-channel and n x 64-channel.16
8 OA&M.17
8.1 General .17
8.1.1 OA&M scope .17
8.1.2 Principles.17
8.2 RFHI administration .17
8.3 RFHI operations and maintenance .17
8.4 RFHI accounting .17
9 RFHI signalling .18
9.1 General .18
9.2 Essential requirements .18
9.2.1 General.18
9.2.2 Outgoing call (CRF-F to RFH).18
9.2.3 Incoming call (RFH to CRF-F).19
9.2.4 Call clearing.19
9.3 Signalling reductions.19

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ETS 300 458: October 1995
Annex A (informative): Requirements on common channel signalling system . 20
Annex B (informative): Bibliography . 21
History. 22

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ETS 300 458: October 1995
Foreword
This European Telecommunication Standard (ETS) has been produced by the Network Aspects (NA)
Technical Committee of the European Telecommunications Standards Institute (ETSI).
Transposition dates
Date of adoption of this ETS: 31 October 1995
Date of latest announcement of this ETS (doa): 31 January 1996
Date of latest publication of new National Standard
or endorsement of this ETS (dop/e): 31 July 1996
Date of withdrawal of any conflicting National Standard (dow): 31 July 1996

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ETS 300 458: October 1995
Blank page
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ETS 300 458: October 1995
1 Scope
Applicability to frame mode services
The Remote Frame Handler (RFH) is an Integrated Services Digital Network (ISDN) frame handler, as
defined in CCITT Recommendation Q.933 [4]:
- which is assumed to be remote with respect to the local connection-related function (refer to CCITT
Recommendation I.324 [3]); and
- which is accessed by its subscribers via a two-step frame mode call establishment (CCITT
Recommendation Q.933 [4], case A).
This European Telecommunication Standard (ETS) defines a manufacturer-independent interface
between the local Connection Related Function (CRF) and the RFH, supporting a specific set of services.
This interface is called the Remote Frame Handler Interface (RFHI).
The RFHI can operate:
a) as an ISDN network-internal interface, in case the RFH belongs to the ISDN;
b) as an inter-network interface, in case the RFH belongs to another network;
c) as a private-public network interface.
However, the existence of this specification does not preclude alternative implementations of a network-
internal interface for Frame Relay Bearer Service (FRBS) provided by a RFH.
Scope reduction
This ETS specifies the interface between the local CRF and the RFH. It defines those additional
requirements that are a direct result of standardizing this interface. Requirements to the ISDN and
particularly to the RFH which are inherent to the provisioning of frame relay services by the ISDN/RFH
and, therefore, are not a direct result of this interface, are specified in other standards. For such
requirements this ETS makes reference to those standards.
Combination of the RFHI with the Packet Handler access point Interface (PHI), as specified in
ETS 300 099 [8] is outside the scope of this ETS.
Supported ISDN frame mode services and conformance statement
The RFHI specification supports all case A services as defined in ETS 300 399-2 [10]; see clause 5 for
details. No other services are supported by the RFHI specification.
The RFHI may be used to offer a subset of the frame relay services supported by the RFHI specification.
Conformance to the RFHI specification is ensured by conforming to the sections of the specification that
are relevant for the support of the subset of frame relay services to be offered with the RFHI.

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ETS 300 458: October 1995
2 Normative references
This ETS incorporates by dated and undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text and the publications are listed
hereafter. For dated references, subsequent amendments to or revisions of any of these publications
apply to this ETS only when incorporated in it by amendment or revision. For undated references the latest
edition of the publication referred to applies.
[1] CCITT Recommendation E.164: "Numbering plan for the ISDN era".
[2] CCITT Recommendation E.165: "Timetable for coordinated implementation of
the full capability of the numbering plan for the ISDN era (Recommendation
E.164)".
[3] CCITT Recommendation I.324: "ISDN Network Architecture".
[4] CCITT Recommendation Q.933 (1992): "Digital Subscriber Signalling System
No 1 (DSS1) - Signalling specification for Frame Mode Bearer Service".
[5] ETS 300 011 (1992): "Integrated Services Digital Network (ISDN); Primary rate
user-network interface; Layer 1 specification and test principles".
[6] ETS 300 089 (1992): "Integrated Services Digital Network (ISDN): Calling Line
Identification Presentation (CLIP) supplementary service; Service description".
[7] ETS 300 090 (1992): "Integrated Services Digital Network (ISDN): Calling Line
Identification Restriction (CLIR) supplementary service; Service description".
[8] ETS 300 099 (1992): "Integrated Services Digital Network (ISDN); Specification
of the Packet Handler access point Interface (PHI)".
[9] ETS 300 399-1 (1995): "Frame relay services; Part 1: General description".
[10] ETS 300 399-2 (1995): "Frame relay services; Part 2: Integrated Services Digital
Network (ISDN); Frame relay bearer service; Service definition".
[11] ETS 300 402-1: "Integrated Services Digital Network (ISDN); Digital Subscriber
Signalling System No. one (DSS1); User-network interface data link layer;
Part 1: General aspects [ITU-T Recommendation Q.920 (1993), modified]".
[12] ETS 300 402-2: "Integrated Services Digital Network (ISDN); Digital Subscriber
Signalling System No. one (DSS1); User-network interface data link layer;
Part 2: General application protocol specification [ITU-T Recommendation
Q.921 (1993), modified]".
[13] ETS 300 403-1: "Integrated Services Digital Network (ISDN); Digital Subscriber
Signalling System No. one (DSS1); User-network interface layer 3 specification
for basic call control; Part 1: Protocol specification [ITU-T Recommendation
Q.931 (1993), modified]".
[14] ETS 300 403-2: "Integrated Services Digital Network (ISDN); Digital Subscriber
Signalling System No. one (DSS1); User-network interface layer 3 specification
for basic call control; Part 2: Specification and Description Language (SDL)
diagrams".
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ETS 300 458: October 1995
3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of this ETS, the following definitions apply:
access channel: The channel used to access the RFH. This may be a 64 kbit/s or n x 64 kbit/s multiple-
rate (see ETS 300 289) bearer channel.
access network: The set of ISDN CRFs providing the connection of the access channel between a
subscriber and the RFH.
administrative procedures: These RFHI Operations, Administration and Maintenance (OA&M)
procedures are separately activated on both sides of the interface. Synchronisation is not automated, i.e.
consistency has to be ensured externally. No signalling on the RFHI is involved.
CRF-F: CRF physically connected to the RFH.
CRF-S: CRF to which subscribers are connected. Synonym for "local CRF" as defined in CCITT
Recommendation I.324 [3].
incoming call: Call in the direction from RFH to CRF-F (CRF-S).
local RFHI access: The configuration where the ISDN subscriber accessing frame mode services is
directly connected to the CRF-F, i.e. CRF-F equal to CRF-S.
outgoing call: Call in the direction from CRF-S (CRF-F) to RFH.
remote RFHI access: The configuration where the ISDN subscriber accessing frame mode services is
connected to the CRF-F via a CRF-S, different from the CRF-F.
RFHI OA&M: The RFHI specification deals only with those RFHI related OA&M aspects, that require the
coordination of CRF-F/S and RFH. These aspects are called "RFHI OA&M". OA&M requirements that are
local to the CRF-F/S side or the RFH side of the RFHI are not within its scope.
RFHI: The interface between the access network and the RFH.
3.2 Abbreviations
For the purposes of this ETS, the following abbreviations apply:
CLIP Calling Line Identification Presentation
CLIR Calling Line Identification Restriction
CRF Connection Related Function
CRF-F CRF at RFH side
CRF-S CRF at Subscriber side
DSS1 Digital Subscriber Signalling System No. one
FM Frame Multiplexer
FRBS Frame Relay Bearer Service
OA&M Operations, Administration and Maintenance
PCM 30 30 channel Pulse Code Modulation
PRA Primary Rate Access
PVC Permanent Virtual Circuit
RFH Remote Frame Handler
RFHI Remote Frame Handler Interface
SS7 Signalling System No. 7
SVC Switched Virtual Call
TE Terminal Equipment
UUS1 User-to-User Signalling, service 1

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ETS 300 458: October 1995
4 Reference configuration and functional model
4.1 RFHI applications
4.1.1 RFHI as network-internal interface
If the ISDN itself provides the FRBS with CCITT Recommendation Q.933 [4] case A procedures, the RFHI
may be used as a network-internal interface, e.g. when the ISDN is implemented with different physical
equipment and in a multi-vendor environment. This RFHI application is illustrated in figure 1.
RFHI
S/T
RFH
ISDN providing
case A FRBS
Figure 1: RFHI as network-internal interface
4.1.2 RFHI as inter-network interface
Frame relay services may also be provided by networks (e.g. public data networks) other than the ISDN
the subscriber is connected to. CCITT Recommendation Q.933 [4] case A procedures may be used to
access such services of other networks. This specification may therefore be used as an inter-network
interface between the ISDN and another network providing frame relay services to the ISDN subscriber.
This RFHI application is illustrated in figure 2.
RFHI
S/T
RFH
Network providing
ISDN
case A FRBS
Figure 2: RFHI as inter-network interface

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ETS 300 458: October 1995
4.1.3 RFHI at T reference point
The RFHI may coincide with the T reference point, in either of the two previous applications. This
application is illustrated in figure 3.
T/RFHI
S
RFH
Netw ork providing
private ISDN
case A FRBS
Figure 3: RFHI at T reference point
4.2 Reference configuration
4.2.1 Network configuration
With respect to frame relay services provided by a RFH, the network consists of two parts:
- the RFH;
- the CRFs between the subscriber and the RFH: the access network.
The RFH is a functional entity providing FRBSs remotely for a number of ISDN subscribers. FRBS in an
ISDN may be provided by more than one of such RFHs, each serving a subset of ISDN subscribers
identified by a CCITT Recommendation E.164 [1] number. A situation where complete CRF-Ss are served
by the same RFH is a special case of this.
4.2.2 Access network configuration
Within the access network, some CRFs are identified as having special relevance within the network
configuration for frame relay, with respect to a certain ISDN subscriber:
- CRF-S: CRF to which the subscriber is connected (local CRF as defined in CCITT
Recommendation I.324 [3]);
- CRF-F: CRF physically connected to the RFH serving the subscriber;
- Transit CRF: CRF between CRF-S and CRF-F, switching the subscribers access cha
...