ETSI ETS 300 215 ed.1 (1992-12)

Network Aspects (NA); Metropolitan Area Network (MAN); Physical layer convergence procedure for 139,264 Mbit/s

DE/NA-053029

Omrežni vidiki (NA) – Velemestno omrežje (MAN) – Konvergenčni postopek na fizični plasti za hitrost 139,264 Mbit/s

General Information

• Status: Published
• Publication Date: 09-Dec-1992
• Technical Committee: NA 5 - Broadband Networks
• Current Stage: 12 - Completion
• Due Date: 04-Dec-1992
• Completion Date: 10-Dec-1992
• Ref Project: SIST ETS 300 215 E1:2003 - Network Aspects (NA); Metropolitan Area Network (MAN); Physical layer convergence procedure for 139,264 Mbit/s

Standards Content (Sample)

SLOVENSKI STANDARD
SIST ETS 300 215 E1:2003
01-december-2003
2PUHåQLYLGLNL1$±9HOHPHVWQRRPUHåMH0$1±.RQYHUJHQþQLSRVWRSHNQD
IL]LþQLSODVWL]DKLWURVW0ELWV
Network Aspects (NA); Metropolitan Area Network (MAN); Physical layer convergence
procedure for 139,264 Mbit/s
Ta slovenski standard je istoveten z: ETS 300 215 Edition 1
ICS:
35.110 Omreževanje Networking
SIST ETS 300 215 E1:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

SIST ETS 300 215 E1:2003

---------------------- Page: 2 ----------------------

SIST ETS 300 215 E1:2003
EUROPEAN ETS 300 215
TELECOMMUNICATION December 1992
STANDARD
Source: ETSI TC-NA Reference: DE/NA-053029
ICS: 33.040
Key words: Network, access, MAN
Network Aspects (NA);
Metropolitan Area Network (MAN)
Physical layer convergence procedure for
139,264 Mbit/s
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
Postal address: F-06921 Sophia Antipolis CEDEX - FRANCE
Office address: 650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
X.400: c=fr, a=atlas, p=etsi, s=secretariat - Internet: [e-mail]
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 1992. All rights reserved.

---------------------- Page: 3 ----------------------

SIST ETS 300 215 E1:2003
Page 2
ETS 300 215: December 1992
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.

---------------------- Page: 4 ----------------------

SIST ETS 300 215 E1:2003
Page 3
ETS 300 215: December 1992
Contents
Foreword .5
1 Scope .7
2 Normative references.7
3 Definitions.7
4 Symbols and abbreviations .7
1)
5 Physical Layer Convergence Procedure (PLCP) for(E4 based systems .8
5.1 Introduction .8
5.1.1 E4 relationship to the PLCP .8
5.2 The PLCP frame format.8
5.3 PLCP field definitions.9
5.3.1 Framing octets (A1, A2) .9
5.3.2 Path overhead identifier (P0.P36) .10
5.3.3 PLCP path overhead octets .10
5.3.3.1 PLCP path user channel (F1) .10
5.3.3.2 Bit Interleaved Parity - 8 (B1).10
5.3.3.3 PLCP path status (G1) .11
5.3.3.4 DQDB layer management information octets (M1, M2) .11
5.3.3.5 Stuffing (octet C1).12
5.3.3.6 Growth octets (Z1.Z31).12
5.3.4 Trailer octets.12
5.4 PLCP behaviour during faults .12
5.5 PLCP behaviour during DQDB layer out of service .13
5.6 PLCP framing .14
5.6.1 Link status signal operations table .15
5.6.2 Physical layer frame timing operations table.16
History.17

---------------------- Page: 5 ----------------------

SIST ETS 300 215 E1:2003
Page 4
ETS 300 215: December 1992
Blank page

---------------------- Page: 6 ----------------------

SIST ETS 300 215 E1:2003
Page 5
ETS 300 215: December 1992
Foreword
This European Telecommunication Standard (ETS) has been prepared by the Network Aspects (NA)
Technical Committee of the European Telecommunications Standards Institute (ETSI).
This ETS details the physical layer convergence procedure for an European Metropolitan Area Network
(MAN) based on the Distributed Queue Dual Bus (DQDB) access method as defined in IEEE Standard
802.6 [6] operating at a transmission rate of 139,264 Mbit/s in accordance with CCITT Recommendation
G.751 [1].

---------------------- Page: 7 ----------------------

SIST ETS 300 215 E1:2003
Page 6
ETS 300 215: December 1992
Blank page

---------------------- Page: 8 ----------------------

SIST ETS 300 215 E1:2003
Page 7
ETS 300 215: December 1992
1 Scope
This European Telecommunication Standard (ETS) defines the physical layer convergence procedure at
139,264 Mbit/s for use in the context of a subnetwork of a Metropolitan Area Network (MAN). Additional
slot mappings for use in transit networks and use of methods defined in this ETS for other purposes are
outside the scope of this ETS.
Methods of testing will be the subject of separate arrangements.
2 Normative references
This ETS incorporates, by dated or 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 G.751 (1988): "Digital multiplexing equipments
operating at the third order bit rate of 34 368 kbit/s and the fourth order bit rate
of 139 264 kbit/s and using positive justification".
[2] CCITT Recommendation G.703 (1991): "Physical/electrical characteristics of
hierarchical digital interfaces".
[3] CCITT Recommendation G.707 (1991): "Synchronous digital hierarchy bit
rates".
[4] CCITT Recommendation G.708 (1991): "Network node interface for the
synchronous digital hierarchy".
[5] CCITT Recommendation G.709 (1991): "Synchronous multiplexing structure".
[6] IEEE Standard 802.6 (1990): "Distributed Queue Dual Bus (DQDB) Subnetwork
of a Metropolitan Area Network (MAN)".
3 Definitions
For the purposes of this ETS, the definitions as defined in IEEE Standard 802.6 [6] shall apply.
4 Symbols and abbreviations
For the purposes of this ETS, the symbols and abbreviations as defined in IEEE Standard 802.6 [6] shall
apply.

---------------------- Page: 9 ----------------------

SIST ETS 300 215 E1:2003
Page 8
ETS 300 215: December 1992
1)
5 Physical Layer Convergence Procedure (PLCP) for(E4 based systems
5.1 Introduction
This ETS provides a convergence procedure in which the Distributed Queue Dual Bus (DQDB) layer is
mapped into a standard transmission system according to CCITT Recommendations G.751 [1] and
G.703 [2] operating at 139,264 Mbit/s as used in public networks. Beyond the provisions of CCITT
Recommendations G.751 [1] and G.703 [2], a 125 μs framing period is provided to support n x 64 kbit/s
channels based on octets.
5.1.1 E4 relationship to the PLCP
The rate, format, electrical characteristics and other attributes of the E4 signal shall be as defined in
CCITT Recommendations G.751 [1] and G.703 [2]. The first 2 octets of each CCITT Recommendation
G.751 [1] frame shall not be used for the PLCP. They are left for E4 synchronisation (i.e. frame alignment)
and overhead bits compatible with existing equipment.
NOTE 1: The coding of the two octets shall be (111110100000 A NNN), where A means the
alarm indication to the remote end bit and NNN are three bits reserved for national
use. The "sliding" of the 2 octets through the 125 μs frame shall be done via full octets.
Therefore, the net bit rate available to the PLCP is 138,503 Mbit/s. The nominal frame rate is 47,563 kHz.
NOTE 2: The PLCP shall provide sufficient buffering or other provisions to accommodate the
"jump" resulting from the passing of the 2 unavailable octets.
The 125 μs frame is not in any way aligned with the 21,0247 μs (47,563 kHz) frame of the transmission
system. The E4 payload slots are only octet aligned to the E4 overhead octets.
5.2 The PLCP frame format
A frame duration of 125 μs is chosen to easily accommodate n x 64 kbit/s channels based on octets. 4
octets shall be added to each DQDB slot of 53 octets to provide framing and overhead functions so that
each row contains 57 octets. 37 of these rows are placed into one 125 μs frame. 55 to 57 octets (nominal)
shall be left as a trailer depending on whether 5 or 6 E4 overhead double octets occurred during the 125
μs frame. The complete frame structure is shown in figure 1. Each row of bits in the PLCP frame format
illustrated in figure 1 shall be transmitted in order from left to right, top to bottom.

1)
The designation E4 is used for a 139,264 Mbit/s transmission system according to CCITT Recommendation G.751 [1]. It is
the 4th level of the plesiochronous digital hierarchy.

---------------------- Page: 10 ----------------------

SIST ETS 300 215 E1:2003
Page 9
ETS 300 215: December 1992
1 1 1 1 53 octets
A1 A2 P36 Z31 First DQDB Slot
A1 A2 P35 Z30 DQDB Slot
A1 A2 P6 Z1 DQDB Slot
A1 A2 P5 F1 DQDB Slot
A1 A2 P4 B1 DQDB Slot
A1 A2 P3 G1 DQDB Slot
A1 A2 P2 M2 DQDB Slot
A1 A2 P1 M1 DQDB Slot 55 to 57 octets
A1 A2 P0 C1 Last DQDB Slot Trailer
125 μs
A1,A2: framing octets.
P0.P36: path overhead identifier octet.
C1: cycle stuff counter.
M1,M2: DQDB layer management information octets.
G1: PLCP path status.
B1: Bit Interleaved Parity-8 (BIP-8).
F1: PLCP path user channel.
Z1.Z31: growth octets.
Figure 1: PLCP frame format
5.3 PLCP field definitions
(Refer to figure 1). The values of fields are described as bit patterns. The leftmost bit of each octet is the
most significant.
5.3.1 Framing octets (A1, A2)
The first two columns (A1, A2) may be used to provide slot delineation. The encoding of the A1 and A2
octets is
A1 A2
11110110 00101000
These codes are the same patterns as used in the Synchronous Digital Hierarchy (SDH) (CCITT
Recommendations G.707 [3], G.708 [4] and G.709 [5]). Alternatively, slot delineation based on the Header
Check Sequence (HCS) of the DQDB header may be used.

---------------------- Page: 11 ----------------------

SIST ETS 300 215 E1:2003
Page 10
ETS 300 215: December 1992
5.3.2 Path overhead identifier (P0.P36)
The third column identifies the PLCP overhead octets contained in the fourth column of figure 1. The
leftmost 6 bits of these octets provide numbering of the 32 rows. The 7th bit is reserved and the rightmost
bit Least Significant Bit (LSB) is a parity bit. The reserved bit shall be set to (0). The parity bit provides odd
parity over this field.
Table 1 defines the codes P0.P36, which shall be generated by the PLCP at each node. All other codes
shall be invalid. A code shall also be considered invalid if the parity bit contained in the LSB is not correct.
The response to invalid codes is described in subclause 5.6.
Table 1: Path overhead indentifier codes
P36 100 100 0 1
:: :
:: :
P7 000 111 0 0
P6 000 110 0 1
P5 000 101 0 1
P4 000 100 0 0
P3 000 011 0 1
P2 000 010 0 0
P1 000 001 0 0
P0 000 000 0 1
5.3.3 PLCP path overhead octets
The PLCP path is defined between two adjacent peer PLCP entities. The F1, B1, G1 and C1 PLCP path
overhead octets are related to PLCP operation and shall be terminated/generated at each PLCP on the
subnetwork. The M1 and M2 octets are provided for the transport of DQDB layer management information
octets and shall not be processed by the PLCP sublayer.
5.3.3.1 PLCP path user channel (F1)
The F1 octet is the user channel, which is allocated for user communication purposes between adjacent
PLCPs. The use of this octet in DQDB subnetworks is for further study. The default code for this octet
shall be (00000000).
5.3.3.2 Bit Interleaved Parity - 8 (B1)
One octet is allocated for PLCP path error monitoring. This function shall be a Bit Interleaved Parity —
8 (BIP-8) code using even parity. The PLCP path BIP-8 is calculated over the 37 x 54 octet structure
(columns 4 to 57, 1 PLCP path overhead octet and 53 DQDB slot octets per row) of the previous PLCP
frame and inserted into the B1 octet of the current PLCP frame.
A BIP-8 is an 8 bit code in which the first bit represents even parity calculated over the first bit of each
octet in the 37 x 54 octet structure, the second bit represents even parity over the second bit of each octet
in the 37 x 54 octet structure, etc. Therefore, the BIP-8 code provides for 8 separate even parity codes
covering the corresponding bit of each octet in the 37 x 54 octet structure.

---------------------- Page: 12 ----------------------

SIST ETS 300 215 E1:2003
Page 11
ETS 300 215: December 1992
5.3.3.3 PLCP path status (G1)
The G1 octet is allocated to convey the received PLCP status and performance back to the transmitting
PLCP. This octet permits the status of the full duplex PLCP path to be monitored at either PLCP entity.
The G1 octet shall consist of:
- 4 bits for the Far End Block Error (FEBE) code;
- 1 bit for the Alarm Signal (AS);
- 3 bits for a Link Status Signal (LSS).
This is illustrated in figure 2.
FEBE (4) AS (1) LSS (3)
Figure 2: PLCP path status (G1)
The first four bits of the G1 octet are the FEBE code which may be used to convey the count of
interleaved-bit blocks that have been detected to be in error by the BIP-8 code in the preceding frame. If
implemented, this count shall have nine legal codes, namely zero (0000) to eight (1000) errors. If not
implemented, the code shall be (1111). The remaining six possible codes (100
...