1AA 00014 0004 (9007)A4All rights reserved. Passing on and copying of this document, use and communication of its contents not permitted without written authorization. Dimensioning Rules for CS and PS Traffic with BSS Software Release B11 (TDM transport) Ed MRD 03 Released DMCPTBE3.DOC v 5 3DC 20003 0031 UZZZA 1/47 All rights reserved. Passing on and copying of this document, use and communication of its contents not permitted without written authorization. CONTENTS 1. REFERENCE DOCUMENTS ....................................................................................... 4 2. INTRODUCTION .................................................................................................. 5 3. DEFINITIONS ...................................................................................................... 5 4. AIR INTERFACE ................................................................................................... 6 5. A-BIS INTERFACE................................................................................................. 7 5.1 Number of time-slots available per A-bis Multidrop link ......................................... 7 5.2 Usage of A-bis timeslots ............................................................................... 7 5.3 Transport of Signalling on the A-bis interface ..................................................... 8 5.4 Two A-bis-links per BTS ................................................................................ 9 6. A-TER INTERFACE...............................................................................................11 6.1 Introduction .............................................................................................11 6.2 Specific A-ter timeslots ...............................................................................12 6.3 Mixed A-ter CS/PS links ...............................................................................13 6.4 Sum up of A-ter timslots configuration.............................................................13 7. GB INTERFACE ..................................................................................................15 7.1 Gb Interface over Frame Relay ......................................................................15 7.2 Gb Interface over IP ...................................................................................16 8. BSC DIMENSIONNING RULES...................................................................................18 8.1 BSC equipment overview..............................................................................18 8.2 BSC A-bis connectivity.................................................................................19 8.3 BSC A-ter connectivity ................................................................................23 8.4 BSC Evolution: STM1 connectivity ...................................................................26 8.5 CS Traffic capacity.....................................................................................27 8.6 Signaling on A interface ...............................................................................29 8.7 A signaling over IP......................................................................................30 9. TRANSCODER DIMENSIONING RULES .........................................................................32 9.1 Connection to the G2 TC..............................................................................32 9.2 Connection to the 9125 TC ...........................................................................32 9.3 Minimum number of A/A-ter links ...................................................................33 9.4 Introduction of Wide Band AMR......................................................................33 10. MFS DIMENSIONING RULES ............................................................................34 1AA 00014 0004 (9007)A4 10.1 Common rules for 9130 and 9135 MFS ..............................................................34 10.2 9135 MFS .................................................................................................34 10.3 9130 MFS Evolution ....................................................................................35 Ed MRD 03 Released DMCPTBE3.DOC v 5 3DC 20003 0031 UZZZA 2/47 1AA 00014 0004 (9007)A4 All rights reserved. Passing on and copying of this document, use and communication of its contents not permitted without written authorization. 10.4 Number of GSL channels ..............................................................................39 11. ANNEX 1: BSS STANDARD TRAFFIC MODEL..........................................................40 11.1 BSS traffic model for CS traffic: .....................................................................40 11.2 SS7 LINK DIMENSIONNING .............................................................................41 11.3 BSS traffic model for PS traffic ......................................................................42 12. ANNEX 2: A-BIS INTERFACE CONFIGURATION ......................................................44 12.1 Number of time-slots required with the different Signaling Multiplexing schemes.........44 12.2 Configurations with 2 A-bis links ....................................................................46 Ed MRD 03 Released DMCPTBE3.DOC v 5 3DC 20003 0031 UZZZA 3/47 1AA 00014 0004 (9007)A4 All rights reserved. Passing on and copying of this document, use and communication of its contents not permitted without written authorization. 1. REFERENCE DOCUMENTS [1] 3DC 21006 0003 TQZZA Use of Moderation Factor for BSS traffic assessment [2] 3DC 21016 0003 TQZZA 9120 Base Station Controller Product Description [3] 3DC 21016 0005 TQZZA 9135 MFS Product Description [4] 3DC 21034 0001 TQZZA G2 Transcoder Product Description [5] 3DC 21016 0007 TQZZA 9125 Compact Transcoder Product Description [6] 3DC 21150 0348 TQZZA GSM/GPRS/EDGE Radio Network Design Process For AlcatelLucent BSS Release B11 [7] 3DC 21019 0007 TQZZA 9130 BSC/MFS Evolution Product Description [8] 3DC 21144 0063 TQZZA Packet transmission feature in release B9 [9] 3DC 21144 0120 TQZZA Functional Feature Description: Gb over IP In Release B10 [10] 3DC 20003 0029 UZZA Network Engineering guidelines for IP transport in the BSS [11] 3DC 21144 0122 TQZZA Functional Feature Description: STM-1 connectivity in the BSS Ed MRD 03 Released DMCPTBE3.DOC v 5 3DC 20003 0031 UZZZA 4/47 for wording simplification purpose. [3]. One GCH uses one A-bis and one A-ter nibble. A-ter and Gb interface. . . [5].Within the MFS: .“BSC” refers to both 9120 BSC and 9130 BSC Evolution. and [7].All rights reserved. 3.The GPU board is the GPRS processing board in the 9135 MFS. [4]. A-bis. . 9135 MFS and 9130 BSC/MFS Evolution equipments with the BSS release B11 When not explicitly otherwise mentioned. . 1AA 00014 0004 (9007)A4 In this document. A 16 kbit/s channel on the A-bis interface is called an A-bis nibble. DEFINITIONS A 64 kbit/s channel on the A-bis interface is called an A-bis timeslot. use and communication of its contents not permitted without written authorization. A 16 kbit/s transmission channel established for carrying (E)GPRS traffic is called a GCH (GPRS channel). EDGE may be used instead of E-GPRS. 2.“BTS” refers to 9100 BTS.DOC v 5 3DC 20003 0031 UZZZA 5/47 . Ed MRD 03 Released DMCPTBE3. [6]. .“MFS” refers to both 9135 MFS and 9130 MFS Evolution. The reader must have some knowledge of the BSS architecture to understand this document.The GP board is the GPRS processing board in the 9130 MFS Evolution. Then it provides dimensioning rules of the 9120 (G2) BSC. INTRODUCTION This document first provides the rules to dimension the interfaces in the BSS: Air. more details about Alcatel Lucent BSS can be found in documents ref [2]. Passing on and copying of this document. use and communication of its contents not permitted without written authorization. - At least one static SDCCH (SDCCH/4 or SDCCH/8) must be positioned on the BCCH TRX for recovery purpose. - All TRX can be declared as Full rate or Dual Rate TRX. - Maximum number of TRX per cell: 16. SDCCH) per TRX is 4. except on G3 TRX (non Edge) on which it is 3. - With one CCCH. - There are one or two CCCH timeslots devoted to CCCH per cell. 4. - With 2 CCCH. These SDCCH timeslot can be static or dynamic. all SDCCH are in the outer zone. 1AA 00014 0004 (9007)A4 . - The maximum number of signaling time slots (BCCH. - In a concentric cell.All rights reserved. - The maximum number of SDCCH timeslots per TRX is 3 (24 SDCCH). up to 22 SDCCH time slots can be configured (176 SDCCH). AIR INTERFACE General / CS traffic: - Maximum number of TRX per BTS: 24. - When BCCH is combined. 2nd CCCH.In a concentric cell. the whole packet traffic is in the primary band of the cell. a second CCCH cannot be configured. the whole packet traffic is in the outer zone. up to 11 SDCCH timeslots can be configured per cell (88 SDCCHs). - In a multiband cell.In a multiband cell. Packet traffic: Max number of TRX supporting GPRS per cell 16 Max PDCH per TRX 8 Max MS in DL packet transfer mode per PDCH 10 Max MS in UL packet transfer mode per PDCH 6 Max MS in packet transfer mode per PDCH 16 Max TS allocated to a MS in packet transfer mode 61 . Ed MRD 03 Released DMCPTBE3. all SDCCH are in the primary band of the cell. . Passing on and copying of this document. 1 The “support of multi-slot class 30-33” feature in B10 has allowed to increase this figure from 5 (B9) to 6 (B10).In case of cell split over two BTS. Mixture of DR TRX and FR TRX are supported. the packet traffic of a cell is supported by only one BTS.DOC v 5 3DC 20003 0031 UZZZA 6/47 . The type of the multidrop link: Closed Loop or Open Chain. then the time-slot used for transmission supervision can be saved (because the OML of 9100 BTS supports also the transmission supervision information) 5. This makes sense when CS3/CS4 or EDGE has been activated. use and communication of its contents not permitted without written authorization. One timeslot on the air interface is mapped on one basic 16kbit/s nibble on the A-bis interface. The table below indicates the number of time-slots available per PCM link according to the possible choices: OPEN CHAIN MULTIDROP CLOSED LOOP MULTIDROP 31 (**) 29 31 30 WITH TS0 TRANSPARENCY TS0 USAGE (*) Number of Time Slots available per A-bis link (*): TS0 usage is not possible with BSC Evolution.All rights reserved. If the cell transports voice and GPRS up to CS-2 only.Whether time-slot zero (TS0) transparency2 is used or not. and if TS0 transparency is used. Passing on and copying of this document. (**) (Recall for history. As a consequence. which is reserved by the transmission equipment for O&M purpose.2 Usage of A-bis timeslots On the A-bis interface. The number of extra timeslots per BTS is determined by the operator. Additional extra timeslots can be configured for the transport of packet.1 Number of time-slots available per A-bis Multidrop link This number depends on: .DOC v 5 3DC 20003 0031 UZZZA 7/47 . 5. no extra timeslots are needed. and timeslots devoted to signaling. there are basic timeslots. . each TRX corresponds to two A-bis basic timeslots. Time Slot 0 Usage means the BSS can use TS0. There is a maximum of: 2 Time slot 0 transparency means the BSS cannot use TS0. Improvement with 9100 BTS. compared to G2 BTS): In case all BTSs of a Multidrop are 9100 BTSs. extra timeslots. A-BIS INTERFACE 5. Ed MRD 03 Released DMCPTBE3. The granularity is one A-bis 1AA 00014 0004 (9007)A4 timeslot. This configuration is not recommended. One HDLC is used per TRX. 5.3 Transport of Signalling on the A-bis interface 5. Each RSL is statically allocated a 16 kbits/s bandwidth. There is one OML per BTS.3. There are three types of Signaling Multiplexing: . .3. as it is wasting bandwidth on the A-bis interface and HDLC resources. This feature requires that the TS0 of each TRX of the BTS does not carry user traffic but signaling (BCCH or SDCCH) only.. The following section presents the various signaling multiplexing mode offered by the Alcatel-Lucent BSS.Statistical Signaling Multiplexing 16k: the basic nibble corresponding to the radio timeslot 0 of each TRX carries the RSL of this TRX and possibly the OML of the BTS. Corresponding to TRX belonging to the same BTS.Static Signaling Multiplexing consists of multiplexing on one A-bis timeslot up to 4 RSLs. DR cannot be supported. Maximum one SDCCH should be configured per TRX. signaling links are transported in independent 64 kbit/s Abis timeslots. DR cannot be supported. When signaling multiplexing is not used. Passing on and copying of this document. There is one RSL per TRX .OML: O&M link.2000 extra timeslots with 9130 BSC 5. use and communication of its contents not permitted without written authorization.717 extra timeslots with 9120 G2 BSC All rights reserved. The OML link is always on the first A-bis link. Ed MRD 03 Released DMCPTBE3.DOC v 5 3DC 20003 0031 UZZZA 8/47 .1 General There are two types of information to be conveyed: . . One HDLC is used per A-bis timeslot carrying signaling.RSL: Radio Signaling Link. Maximum one SDCCH should be configured per TRX.2 A-bis signaling multiplexing modes Signaling multiplexing is specified by the Operator per BTS sector. The OML uses an additional A-bis timeslot. 1AA 00014 0004 (9007)A4 This multiplexing scheme is adapted to small BTS. Statistical Signaling Multiplexing 64k consists of multiplexing on one A-bis time-slot 1.) 5.. The number of SDCCH channels per cell should not exceed 8 * NB_TRX + 8 NB_DR_TRX. The signaling load is specified per BTS sector. Full Rate TRX Dual rate TRX Normal High signaling Normal High signaling signaling load load signaling load load 4:1 2:1 2:1 1:1 Multiplexing ratio for Statistical Signaling Multiplexing 64k - Note: In most cases normal signaling should apply.In case of more than 12 TRX in a BTS. whether RSL multiplexing is 1AA 00014 0004 (9007)A4 used or not4. The whole A-bis timeslot bandwidth is shared by all channels.To configure more extra A-bis timeslots. taking benefit of TWIN TRX introduction. One HDLC is used per A-bis timeslot carrying signaling. . The multiplexing ratio depends on the configuration of the TRX (Dual Rate or Full Rate). In this case 2 A-bis Time Slots are used. It is not possible to mix the RSL of Full-Rate TRX and Dual-Rate TRX in the same 64 kbit/s timeslot.DOC v 5 3DC 20003 0031 UZZZA 9/47 . Passing on and copying of this document. The TCH and the RSL of a TRX are grouped on the same A-bis link. as illustrated in the table below. 2 or 4 All rights reserved. The OML of a BTS is always mapped on the first A-bis link. RSLs3 of a same BTS plus its OML. DR is supported. For this purpose.4 Two A-bis-links per BTS A secondary A-bis link can be used for following purposes: . High signaling load should correspond to exceptional cases (very high paging load and very high location update or SMS rates. and on the signaling load parameter (normal or high) specified by the Operator. 3 3 RSL in one time slot is not possible. use and communication of its contents not permitted without written authorization. Ed MRD 03 Released DMCPTBE3. 4 So in case of multiplexing it implies that TCH of TRX of which RSL are multiplexed together are also on the same A-bis. it is possible to configure a secondary A-bis link with basic A-bis nibbles. DOC v 5 3DC 20003 0031 UZZZA 10/47 . multiplexing mode “per sector” is not supported.e. Ed MRD 03 Released DMCPTBE3. See Annex 2 for more details. Passing on and copying of this document. use and communication of its contents not permitted without written authorization. the 1AA 00014 0004 (9007)A4 All rights reserved. With Statistical signaling multiplexing 64 kbit/s. the multiplexing mode is valid for the whole BTS.All A-bis signaling modes are supported. i. whatever they use FR or HR codecs. A dedicated A-ter-PS link cannot be routed through the Transcoder. When there is enough PS traffic to fill 2 or more A-ter links. On the A-ter CS interface. Ed MRD 03 Released DMCPTBE3. • When it transports PS traffic. It is then called a mixed A-ter CS/PS link.All rights reserved. a 64 kbit/s timeslot supports 4 GCHs. Passing on and copying of this document. doing so avoids connecting the MFS to the transcoder with A-ter E1 not fully devoted to circuit-switched traffic. it is called an A-ter CS link. among which one can be used for GSL. there is an advantage to dedicate complete A-ter E1 to PS rather than mixing PS with CS traffic. • An A-ter CS link can also carry PS traffic. it is called an A-ter PS link.DOC v 5 3DC 20003 0031 UZZZA 11/47 . and between the BSC and the MFS for PS traffic. use and communication of its contents not permitted without written authorization. The same TS sharing between CS and PS is used on the BSC/MFS and MFS/ TC links. Indeed. 6. the minimum number of A-ter links connected to a BSS is 2. there are up to 30 64 kbit/s channels. a 64 kbit/s timeslot transmits information for 4 CS calls. in order to enable MFS installation without O&M interruption 1AA 00014 0004 (9007)A4 on the BSC.1 Introduction The A-ter interface is both the interface between the BSC and the TC for CS traffic. It is possible to configure PS timeslots on all A-ter E1: typical application case is configurations with only 2 A-ter E1 in order to ensure A-ter PS traffic resilience. For an A-ter link fully dedicated to PS. However it is recommended not to carry PS traffic on the first A-ter link so that it can be connected directly to the transcoder. • When an A-ter link transports CS traffic. On the A-ter PS interface. For a mixed A-ter CS/PS link: • The MFS transparently routes the 64 kbit/s timeslots used for voice towards the transcoder. • It is also possible to route both CS and packet traffic towards the transcoder. • The MFS has the possibility to split the traffic on a link towards the transcoder for CS traffic and a link towards the SGSN for PS traffic (Gb). and thus avoids wasting transcoder resource. For the sake of redundancy. A-TER INTERFACE 6. TC G2: Timeslot 15 of each A-ter link is used to convey transmission alarm bits (submultiplexing of TS0 alarms). with B11 MR2 may be used to carry PS traffic in case of MT120-xB TC board with 9130 BSC Evolution.All rights reserved. MT120-xB5 boards: this timeslot is not used anymore for that purpose. . Unless explicitly otherwise mentioned.Transport of O&M information between BSC and OMC-R . .Timeslot 16 can be used for that purpose. From B10 MR2 onwards.9120 BSC: When this connection is performed through the A-ter Interface (not using an external X25 network). N is between 2 and 16.TS 0 of each link: Not usable for traffic. this timeslot becomes usable for CS traffic.Transmission alarm octets: . the O&M links is conveyed in the timeslot 31 of the A-ter 1 to N. the O&M links is conveyed in the timeslot 31 of the A-ter links N°1 & 2.2 Specific A-ter timeslots Some A-ter timeslots are not usable for user traffic.MT120. This is particularly interesting in case of HSL or A signaling over IP. depending on HW generation. . 5 MT120-xB stands for MT120-NB or MT120-WB boards Ed MRD 03 Released DMCPTBE3. TS16 from B10 MR2 onwards is used for CS traffic. .9130 BSC: When this connection is performed through the A-ter Interface (IP over A-ter and not IP over Ethernet).DOC v 5 3DC 20003 0031 UZZZA 12/47 . use and communication of its contents not permitted without written authorization. These improvements are valid only for BSC Evolution. . Timeslots 31 not used for O&M can be used for CS or PS traffic. .Timeslots 16 not used as such were not usable for user traffic. 6. whether such a timeslot is usable or not for traffic is valid for both CS and PS traffic. Starting with B11 MR2 this TS can be used to carry PS traffic. . Timeslots 31 not used for O&M can be used for CS or PS traffic. Some others are or are not usable for user traffic. Passing on and copying of this document. with a default value of 4 and is configurable by the Operator: the IP bandwidth can then be configured between 128 Kbits and 1 Mbit/s with a default value of 256 1AA 00014 0004 (9007)A4 Kbit/s.SS7: . . 26. 13. 14 (two Qmux channels per cluster of 6 A-ter link) is dedicated to the Qmux protocol.All rights reserved. Ed MRD 03 Released DMCPTBE3. . The three other sub channels are used for CS or PS traffic.On A-ter-PS.GSL: . 8. 13. 2. . 61.Qmux protocol (Transmission equipment supervision). 25. Passing on and copying of this document. 2. When not configured.9130 BSC: One 16 kbits/s sub-channel in timeslot 14 of links N° 1. 67. 73. 68. The three other sub channels are used for CS or PS traffic.3 Mixed A-ter CS/PS links The percentage of A-ter timeslots assigned to PS traffic is configured by the Operator at OMC-R. 19. 74 (two Qmux channels per cluster of 6 A-ter link) is dedicated to the Qmux protocol. Each column corresponds to a different proportion of A-ter timeslots devoted to A-ter PS in mixed 1AA 00014 0004 (9007)A4 A-ter links. use and communication of its contents not permitted without written authorization. 62. 6.DOC v 5 3DC 20003 0031 UZZZA 13/47 . 6.9120 BSC: One 16 kbits/s sub-channel in timeslot 14 of links N° 1. 14. 8. the A-ter timeslots shown below as carrying PS traffic (GCH) can be used to carry CS traffic. 7. In pure A-ter CS links. timeslot 28 can be used for CS or PS traffic. . 20. 7. one GSL may be configured on timeslot 28 to convey packet signaling between the BSC and the MFS.4 Sum up of A-ter timslots configuration The following table summarizes the place of the special timeslots usable or not usable for CS/PS traffic and the sharing of timeslots between CS and PS in case of mixed A-ter links. DOC v 5 3DC 20003 0031 UZZZA 14/47 . / GCH 16 SS7 / TCH SS7 / TCH SS7/ GCH SS7 / GCH SS7 / GCH 17 TCH TCH GCH GCH GCH 18 TCH TCH GCH GCH GCH 19 TCH TCH GCH GCH GCH 20 TCH TCH GCH GCH GCH 21 TCH TCH GCH GCH GCH 22 TCH TCH GCH GCH GCH 23 TCH TCH GCH GCH GCH 24 TCH GCH GCH GCH GCH 25 TCH GCH GCH GCH GCH 26 TCH GCH GCH GCH GCH 27 TCH GCH GCH GCH GCH 28 GCH/GSL GCH/GSL GCH/GSL GCH/GSL GCH/GSL 29 GCH GCH GCH GCH GCH 30 GCH GCH GCH GCH GCH 31 GCH/O&M GCH/O&M GCH/O&M GCH/O&M GCH/O&M 1AA 00014 0004 (9007)A4 A-ter CS/PS configuration Ed MRD 03 Released DMCPTBE3. / TCH TCH/Qmux alarm Oct. use and communication of its contents not permitted without written authorization. / GCH GCH/Qmux alarm Oct. Passing on and copying of this document. 0 1 TCH TCH TCH TCH GCH 2 TCH TCH TCH TCH GCH 3 TCH TCH TCH TCH GCH 4 TCH TCH TCH TCH GCH 5 TCH TCH TCH TCH GCH 6 TCH TCH TCH TCH GCH 7 TCH TCH TCH TCH GCH 8 TCH TCH TCH GCH GCH 9 TCH TCH TCH GCH GCH 10 TCH TCH TCH GCH GCH 11 TCH TCH TCH GCH GCH 12 TCH TCH TCH GCH GCH 13 TCH TCH TCH GCH GCH 14 15 TCH/Qmux alarm Oct.All rights reserved. / TCH TCH/Qmux alarm Oct. / TCH GCH/Qmux alarm Oct. DOC v 5 3DC 20003 0031 UZZZA 15/47 . 7. Passing on and copying of this document. GB INTERFACE 7. depending on the hardware and software versions. . However.Through the Transcoder and the MSC.1 Gb Interface over Frame Relay There are 2 ways to connect the MFS and the SGSN via the Gb interface: . A bis A ter A ter A BTS BSC TC MSC BTS FRDN Frame Relay Data Network BTS MFS SGSN 1AA 00014 0004 (9007)A4 Remarks: The links going through the MSC can benefit from the multiplexing capability of the MSC 6 For synchronisation issues. The figure below displays the different types of links between the MFS and the SGSN. This is the recommended solution when the traffic is sufficient to justify A-ter E1s completely devoted to GPRS traffic. because of the GPU synchronization issues6. The links between the MFS and the SGSN or between the MSC and the SGSN can be direct point-topoint physical connections or an intermediate Frame Relay Network can be used. please refer to the 9135 MFS product description [3] or 9130 BSC/MFS Evolution Product description [7].All rights reserved. Ed MRD 03 Released DMCPTBE3.Bypassing the Transcoder and going either directly to the SGSN (through the MSC or not). this is not always possible. use and communication of its contents not permitted without written authorization. please refer to [6]. 1AA 00014 0004 (9007)A4 Seen as single gateway IP@ SGSN Packet Switched Network GboIP: End-to-End architecture Ed MRD 03 Released DMCPTBE3. For more information on the method to determine the Gb peak throughput according to the traffic mix expected within the BSC area and the Gb interface overheads.DOC v 5 3DC 20003 0031 UZZZA 16/47 . the operator may introduced submultiplexing of Gb links between the MFS and the SGSN with an external equipment. Gb over Frame Relay supports static configuration.The maximum number of BVC is 501 per BSS for the 9130 MFS With Gb over frame relay.The maximum number of NS-VC is 124 per BSS .All rights reserved. use and communication of its contents not permitted without written authorization. which takes into account the Gb interface overheads. The peak throughput of the Gb interface per GP or GPU is equal to the peak LLC throughput multiplied by an overhead factor. This overhead factor depends on the mean frame size. Passing on and copying of this document. 7. Gb traffic is transmitted over UDP/IP/Ethernet. Ater(circuit) E1 PDH/SDH network TC A Ater(packet) BSC MSC GE MFS GE Gb Full redundant architecture. In case where the Gb links are not fully used. The maximum number of Frame Relay bearer channels is 124 per GPU board (theoretical value).The maximum number of BVC is 265 per BSS for the 9135 MFS . It is however interesting to reduce the number of bearer channels to one per E1 and at least 2 on 2 different E1 (for redundancy reason). The Gb peak throughput allows determining the required number of E1 links for Gb/frame relay. in order to reduce the number of ports required to the frame relay network towards the SGSN. the traffic is aggregated at GP(U) board level.2 Gb Interface over IP With Gb over IP. . in order to take benefit from the statistical effect of using larger bearer channels. With Gb over Frame Relay. each GP(U) board can address up to 16 IP endpoints of the SGSN. the Gb transport type can be different among the BSCs connected to a same MFS.DOC v 5 3DC 20003 0031 UZZZA 17/47 . the 9120 BSC has not this capability. Passing on and copying of this document. The Gb transport type has to be chosen on a per BSC basis: all the GP(U)s connected to a same BSC shall use Gb over Frame Relay or Gb over IP.The 9130 MFS Evolution . refer to [6]. and is then able to synchronize the MFS through the A-ter PS TDM links. provided that it is equipped with a compatible Gigabit Ethernet Switch. use and communication of its contents not permitted without written authorization. the traffic flows from/to all GP(U)s between MFS and SGSN is aggregated into one single flow over Ethernet: Gb dimensioning is done considering the LLC traffic of a whole MFS traffic plus BSSGP/NS/UDP/IP/Ethernet overheads. Ed MRD 03 Released DMCPTBE3. Gb over IP supports static and dynamic configuration. On the other hand. This feature is available from B10. and [10]. Therefore a TDM link between the TC and the MFS must be kept to synchronize the MFS. The BSC has the capability to retrieve synchronization from the A-ter CS TDM links. On the other hand. 1AA 00014 0004 (9007)A4 For more information on Gb over IP and its dimensioning.The 9135 MFS DS10. Traffic load sharing is possible: for this purpose.Note: the previous figure illustrates Gb over IP for a TDM BSS. over IP together with IP transport in the BSS. on: . With Gb over IP. It is for sure possible to have Gb All rights reserved. but mixing is not allowed. dimensioning is done per BSS with an E1 granularity. 2 9130 BSC Evolution configurations Two main types of configuration are available.1. please refer to the BSC product description [2]. 8. with one telecom sub-rack per BSC. 448 TRX-FR.Standard configurations: BSC Evolution with one telecom sub-rack . in one cabinet: . BSC DIMENSIONNING RULES 8. 40A. 16A.1 BSC equipment overview 8. 24A. 192 TRX-FR. For more details on BSC Evolution hardware. 352 TRX-FR. 48A.Rack Sharing configurations: two BSC Evolution.1. 72A.All rights reserved. use and communication of its contents not permitted without written authorization. 128 TRX-FR. Passing on and copying of this document.1 9120 G2 BSC configurations The G2 BSC range available with the BSS Software Release B11 is: Configuration number 1 2 3 4 5 6 BSC G2 EQUIPMENT 32 TRX-FR. Number of cabinets 1 1 2 2 3 3 6 A-bis-ITF 24 A-bis –ITF 36 A-bis –ITF 54 A-bis –ITF 66 A-bis –ITF 84 A-bis –ITF G2 BSC configurations For more details on G2 BSC HW.DOC v 5 3DC 20003 0031 UZZZA 18/47 . 288 TRX-FR. 64A. please refer to document ref [7] 1AA 00014 0004 (9007)A4 Configuration Ed MRD Number of equipped telecom subracks Number of CCP boards (*) Number of LIU boards BSC-EV-200 1 2 8 BSC-EV-400 1 3 8 BSC-EV-600 1 4 16 BSC-EV-800 1 5 16 BSC-EV-1000 1 6 16 BSC-EV-RS 400-400 (**) 2 6 16 BSC-EV-RS 600-200(**) 2 6 24 BSC-EV-RS 600-400 (**) 2 7 24 BSC-EV-RS 600-600 2 8 32 BSC-EV-RS 800-200 2 7 24 BSC-EV-RS 800-400 2 8 24 03 Released DMCPTBE3. 8. 1 Mix of Full Rate and Dual Rate TRX The Half-Rate Flexibility feature allows defining the number of Dual Rate TRX in each BTS sector (cell).2 BSC A-bis connectivity There is a set of rules to determine the maximum amount of TRX and BTSs that can be connected to a BSC. use and communication of its contents not permitted without written authorization. as dual-rate capable with no loss of capacity in the BSC. Ed MRD 03 Released DMCPTBE3. The table below indicates the number of A-bis TSU and the TRX capacity for each G2 BSC 1AA 00014 0004 (9007)A4 configuration. Passing on and copying of this document. 8. only with BSC Evolution. The optimized half-rate connectivity feature allows declaring all TRX of a cell.2. Configuration Number of equipped telecom subracks Number of CCP boards (*) Number of LIU boards BSC-EV-RS 800-600 2 9 32 BSC-EV-RS 800-800 2 10 32 BSC-EV-RS 1000-200 2 8 24 BSC-EV-RS 1000-400 2 9 24 BSC-EV-RS 1000-600 2 10 32 BSC-EV-RS 1000-800 2 11 32 BSC-EV-RS 1000-1000 2 12 32 BSC Evolution configurations (*) Each CCP handles 200 TRX – The figure here include spare CCP boards. it was not possible to have more than 600 TRX per logical BSC.DOC v 5 3DC 20003 0031 UZZZA 19/47 . 8. (**) These configurations are kept for historical reasons: indeed with B9.2 9120 G2 BSC The A-bis connectivity is provided by a number of A-bis TSU. Each A-bis TSU includes 8 TCUs (Terminal Control Unit) and six G. This feature is available from B6 onwards.703 A-bis interfaces. which allow connecting six A-bis PCM trunks. This feature is available from B10 onwards.All rights reserved.2. 8. BTSs max. Of A-bis TSU Configuration 1 Configuration 2 Configuration 3 Configuration 4 Configuration 5 Configuration 6 1 4 6 9 11 14 Max. nb.e. use and communication of its contents not permitted without written authorization. It is not possible to mix FR TRX and DR TRX in a single TCU.All rights reserved.The traffic channels and the RSL of a given TRX are handled by the same TCU.DOC v 5 3DC 20003 0031 UZZZA 20/47 . BSC G2 EQUIPMENT Nb. 8 FR TRX for configurations (3) & (4). and 12 FR TRX for configurations (5) & (6).Each TCU can handle 6 signaling links (LAPD). of DR-TRX 32 128 192 288 352 448 14 62 92 140 170 218 TRX connectivity for G2 BSC Note: At least one TCU in each BSC rack must be allocated in Full Rate. It is detailed in the table below. . BTSs max. there are still up to 4 potential FR TRX for configurations (1) & (2).Each TCU can handle either Full Rate or Dual Rate traffic (but not both). relative to the A-bis TSU. Cells max. nb. 1AA 00014 0004 (9007)A4 . of FR-TRX Max. Cells Configuration 1 Configuration 2 Configuration 3 Configuration 4 Configuration 5 Configuration 6 23 95 142 214 255 255 32 120 192 240 264 264 14 62 92 140 170 218 14 62 92 140 170 218 BTS and cell connectivity for G2 BSC The following rules. Passing on and copying of this document. i.Each TCU can handle 32 Traffic Channels. All TRX Full Rate All TRX Dual Rate BSC G2 EQUIPMENT max. .All TRX of all BTSs of a same A-bis multidrop are handled by a single A-bis TSU. This is why the maximum number of DR TRX is inferior to half of the maximum number of FR TRX. Ed MRD 03 Released DMCPTBE3. i. . 4 Full-Rate TRX or 2 Half-Rate TRX. must be respected: .e. When the maximum number of DR TRX is reached. The maximum number of BTS and cells depends whether all TRX are configured in Full Rate or in Dual Rate mode. typically: (4 RSLs + 2 OMLs for 4 TRX+ 2 BTSs ) or (3 RSLs + 3 OMLs for 3 TRX+ 3 BTSs). In each cabinet. all RSLs of a given 64 kbit/s A-bis time-slot are handled by All rights reserved. Remarks: .2. the same TCU (this rule applies for both Static and Statistical Signaling Multiplexing) .DOC v 5 3DC 20003 0031 UZZZA 21/47 . RSL.It is possible to mix within a same TCU. which are not multiplexed. Recommendations: . 8. Passing on and copying of this document. . which are multiplexed (static and/or statistical) and RSL.3 9130 BSC Evolution The following table provides the main information on the BSC Evolution A-bis connectivity: 1AA 00014 0004 (9007)A4 Configuration TRX (*) Cell BTS A-bis links BSC-EV-200 200 200 150 96 BSC-EV-400 400 400 255 96 BSC-EV-600 600 500 255 176 BSC-EV-800 800 500 255 176 BSC-EV-1000 1000 500 255 176 BSC-EV-RS 400-400 800 800 510 192 BSC-EV-RS 600-200 800 700 405 272 BSC-EV-RS 600-400 1000 900 510 272 BSC-EV-RS 600-600 1200 1000 510 352 BSC-EV-RS 800-200 1000 700 405 272 BSC-EV-RS 800-400 1200 900 510 272 BSC-EV-RS 800-600 1400 1000 510 352 BSC-EV-RS 800-800 1600 1000 510 352 BSC-EV-RS 1000-200 1200 700 405 272 BSC-EV-RS 1000-400 1400 900 510 272 BSC-EV-RS 1000-600 1600 1000 510 352 BSC-EV-RS 1000-800 1800 1000 510 352 BSC-EV-RS 1000-1000 2000 1000 510 352 A-bis connectivity for BSC Evolution Ed MRD 03 Released DMCPTBE3..In case of Signaling Multiplexing. leaving free some spare capacity in all A-bis TSUs will simplify further extensions. use and communication of its contents not permitted without written authorization. there is at least one TCU configured in Full Rate. Hence up to 3 A-bis closed loop multidrop links can be connected to 1 A-bis-TSU. In case of closed loop multidrop links.6 A-bis open chain multidrop links can be connected to one A-bis TSU. both ends of an A-bis multidrop loop must be connected to the same A-bisTSU.It is recommended not to dimension a BSC over 90% of its maximum connectivity. Indeed. 2. use and communication of its contents not permitted without written authorization. The Optimised Half-Rate Connectivity feature is optional. the BSC Evolution can handle 200 All rights reserved. Extra-timeslots defined on the A-bis links are cross-connected inside the BSC and consume some BSC connectivity. so as to enable a better signaling load distribution at TCU level. 8. In other words. configuring two extra timeslot is equivalent to reducing the number of connectable FR TRX by one.2.DOC v 5 3DC 20003 0031 UZZZA 22/47 . Note : the system maps extra-timeslots on any FR TCU of the A-bis TSU to which the A-bis link is connected. 1AA 00014 0004 (9007)A4 8.(*): Thanks to the Optimised Half-Rate Connectivity feature.However. CS4 and EDGE has no impact on the BSC TRX connectivity.5 Introduction of CS-3. the maximum number of DR TRX is equal to the maximum number of FR TRX divided by 2. However CCPs remain limited to 900 Erlang. Two A-bis extra timeslots are equivalent to one Full Rate TRX in terms of connectivity in the BSC. Passing on and copying of this document. whatever those TRX are FR or HR. When it is not used. Remarks concerning the G2 BSC: . CS-4 and EDGE has impacts on A-bis dimensioning and on the BSC TRX connectivity. TRX per CCP board.2. Ed MRD 03 Released DMCPTBE3.The BTSs can be connected to the same or to different A-bis TSUs.5. . while not increasing the external blocking. adding a new BTS without modifying the arrangement of the already existing BTS(s).5. This allows for example to extend a site. so as to allow reaching 900 Erlang. CS-4 and EDGE 8. 8. A maximum number of calls simultaneously established per CCP board is defined. in Multi-band Cells all radio signaling is concentrated on the primary band.1 Case of the 9120 G2 BSC Introduction of CS-3. it is recommended to mix the 900 MHz BTSs and the 1800 MHz BTSs in each A-bis TSU. In this case.4 Particular case of cell splitting This feature enables to share a cell between 2 BTSs.2 Case of the 9130 BSC Evolution The introduction of CS3.2. 3. there are up to 1024 HDLC channels7 at 64 kbit/s per BSC. The detailed information on how to split an A-ter-link between CS & PS is detailed in section 6.3.2. 8.1 9120 G2-BSC The maximum number of A-ter interfaces (E1 links) is given in the table below. Passing on and copying of this document. For 9120 G2 BSC. If signaling multiplexing is not used on A-bis interface. the maximum number of TRX and BTS indicated in sections 8.16 for O&M transport over A-ter interface.All rights reserved.2 cannot be reached8. among which 441 are available for A-bis signaling (RSL+OML). 1AA 00014 0004 (9007)A4 7 For BSC Evolution installed prior to B10-MR2. The previous board has a capacity of 512 HDLC channels. This maximum number of A-ter interfaces is the total available for CS and PS services. the number of HDLC channel is not a limiting factor (6 HDLC channels per TCU) whatever the multiplexing scheme. 8. Each A-ter link can be either fully dedicated to PS or CS. The new TP-STM1 board must replace the previous TP board. .3 BSC A-ter connectivity 8.6 A-bis Signaling capacity In the 9130 BSC Evolution. Among them: . or it is also possible to split some A-ter links between CS and PS. . so as to save A-bis time slots. With such boards.DOC v 5 3DC 20003 0031 UZZZA 23/47 .24 are reserved for GSL usage.984 are available for RSL and OML.2. The number of RSL (plus possibly one OML) carried per HDLC channel depends on the use of signaling multiplexing as explained in section 5. a hardware upgrade is needed to reach 1024 HDLC channels. the number of DR TRX is limited to 882 (2 DR RSL per signalling timeslot) 8 Without signalling multiplexing. use and communication of its contents not permitted without written authorization. It is recommends to use statistical signaling multiplexing on 64 kbit/s A-bis TS. the following rule applies: Number of TRX (RSL) + number of BTS (OML) < 984 Ed MRD 03 Released DMCPTBE3. Passing on and copying of this document.2 9130 BSC Evolution There is one “A-ter CS pool” and one “A-ter PS” pool per BSC . use and communication of its contents not permitted without written authorization. .A-ter links belonging to the A-ter CS pool can be used to carry CS traffic only or CS and PS traffic (Mixed A-ter links): Pure A-ter-CS and mixed A-ter-CS/PS links can be configured. The maximum number of A-ter interfaces inside each pool is given in the table below: 1AA 00014 0004 (9007)A4 Configuration A-ter CS pool A-ter PS pool BSC-EV-200 10 6 BSC-EV-400 20 12 BSC-EV-600 30 18 BSC-EV-800 38 26 BSC-EV-1000 46 30 BSC-EV-RS 400-400 40 24 BSC-EV-RS 600-200 40 24 BSC-EV-RS 600-400 50 30 BSC-EV-RS 600-600 60 36 BSC-EV-RS 800-200 48 32 BSC-EV-RS 800-400 58 38 BSC-EV-RS 800-600 68 44 BSC-EV-RS 800-800 76 52 BSC-EV-RS 1000-200 56 36 BSC-EV-RS 1000-400 66 42 BSC-EV-RS 1000-600 76 48 BSC-EV-RS 1000-800 84 56 BSC-EV-RS 1000-1000 92 60 A-ter connectivity for BSC Evolution Ed MRD 03 Released DMCPTBE3.DOC v 5 3DC 20003 0031 UZZZA 24/47 . of A-ter itf Configuration 1 Configuration 2 Configuration 3 Configuration 4 Configuration 5 Configuration 6 4 6 10 12 16 18 A-ter connectivity for G2 BSC 8. From B11 onwards. pure A-ter PS links can be also configured.All rights reserved.3. BSC G2 configurations Max. Nb.A-ter links belonging to the A-ter PS pool are dedicated to PS traffic: Only A-ter PS links can be configured. Ed MRD 03 Released DMCPTBE3.In the case of SS7 carried on 2 Mbit/s link (HSL) two A-ter links must be reserved for this. Both HSL 1AA 00014 0004 (9007)A4 All rights reserved. which saves TC resources.DOC v 5 3DC 20003 0031 UZZZA 25/47 . use and communication of its contents not permitted without written authorization. Passing on and copying of this document. should be connected to distinct LIU boards to ensure redundancy even in case of LIU failure. HSL links are directly connected to the MSC. Ed MRD 03 Released DMCPTBE3. in mono-mode/short-haul type9). One STM-1 link can contain up to 63 VC12 containers. Up to 4 STM-1 links can be connected (Optical interfaces. but mix of E1 and STM-1 connections is possible on A-Bis and A-ter. 9 Pluggable O/E converters. 1AA 00014 0004 (9007)A4 For more details please refer to [2] and [11]. are used and enable other STM-1 types. allowing for 100 % STM-1 connectivity. Passing on and copying of this document. and which of the links should be transported over E1 links. BSC STM-1 Gb over FR or Gb over IP ADM MFS E1 E1 ADM SDH Ring ADM STM-1 STM-1 E1 SGSN MSC ADM STM-1 TC BSC STM1 in the BSC Each E1 link is transported transparently in one 2 Mbit/s VC12 container. On any STM1 link can be mapped A-bis. It is available on both A-bis and A-ter interfaces. or a mix of A-bis and A-ter E1s. the Operator can choose which A-bis or A-ter links should be transported over STM-1.All rights reserved. use and communication of its contents not permitted without written authorization. 8. In case of a mixed configuration.DOC v 5 3DC 20003 0031 UZZZA 26/47 .4 BSC Evolution: STM1 connectivity STM1 connectivity is introduced in B11 release for the 9130 BSC Evolution. called SFP (Small Form Factor Pluggable). A-ter. The only HW pre-requisit is that the BSC is equipped with TPSTM1 or TPSTM1-IP boards. DOC v 5 3DC 20003 0031 UZZZA 27/47 . The Erlang figures are based on a 0.1%. 8.1 9120 G2-BSC These following figures are guaranteed with respect to the call mix specified in annex 1. the blocking rate will reach 0.24%.5 CS Traffic capacity The maximum CS traffic capacity is limited by the number of A-ter interface channels available for traffic. Maximum Traffic (ERLANG) Maximum BHCA BSC-EV-200 900 64 800 BSC-EV-400 1800 129 600 1AA 00014 0004 (9007)A4 Configuration Ed MRD 03 BSC-EV-600 2700 194 400 BSC-EV-800 3600 259 200 BSC-EV-1000 4500 324 000 BSC-EV-RS 400-400 3600 259 200 Released DMCPTBE3. The most constraining limit has to be taken into account. instead of 0. which depends on the traffic model.5. 8. Also in that case.1% blocking probability on the A-ter interface.1%.2 9130 BSC Evolution The figures below are guaranteed with respect to the call mix specified in annex 1. use and communication of its contents not permitted without written authorization. The BSC is also limited by its processing power available for signaling handling.All rights reserved. This is reflected by the maximum Busy Hour Call Attempts (BHCA). The Erlang figures are based on a 0. blocking probability on the A-ter interface. G2-BSC configuration Configuration 1 Configuration 2 Configuration 3 Configuration 4 Configuration 5 Configuration 6 Maximum Traffic (ERLANG) 160 Erlang 620 Erlang 1050 Erlang 1300 Erlang 1700 Erlang 1900 Erlang Maximum BHCA 11 520 44 640 75 600 93 600 122 400 136 800 Erlang & BHCA for the 9120 G2 BSC Note that a configuration 6 BSC can reach a 2000 ERLANG capacity with a less constraining traffic model.5. Then the other limit is calculated according to the formula: Erlang traffic load = (Busy hour call attempts * Mean call duration) /3600 8. Passing on and copying of this document. Using the Moderation Factor is also recommended for the assessment of the number of A-ter 1AA 00014 0004 (9007)A4 Interfaces and of transcoders.All rights reserved. To account for this and avoid over-estimating the number of BSC necessary for a given network. use and communication of its contents not permitted without written authorization. Ed MRD 03 Released DMCPTBE3. BSC-EV-RS 600-200 3600 259 200 BSC-EV-RS 600-400 4500 324 000 BSC-EV-RS 600-600 5400 388 800 BSC-EV-RS 800-200 4500 324 000 BSC-EV-RS 800-400 5400 388 800 BSC-EV-RS 800-600 6300 453 600 BSC-EV-RS 800-800 7200 518 400 BSC-EV-RS 1000-200 5400 388 800 BSC-EV-RS 1000-400 6300 453 600 BSC-EV-RS 1000-600 7200 518 400 BSC-EV-RS 1000-800 8100 583 200 BSC-EV-RS 1000-1000 9000 648 000 Erlang & BHCA for the 9130 BSC Evolution The capacity for rack-shared configuration is the sum of the capacity of each logical BSC.3 The moderation factor When dimensioning a network.5. Significantly lower values may even be used in many cases. More details on the Moderation Factor can be found in document [1].8 may be used. a maximum value of 0. Except for very dense urban areas. This comes from the fact that the nominal traffic is not reached simultaneously in each cell and that all TRX or all traffic channels are not all necessary to handle the actual traffic. The value of the Moderation Factor can vary very significantly depending on the network context. one must check that the sum of the nominal traffic generated by the different BTSs does not exceed the maximum traffic handling capacity of the BSC to which they are connected. Passing on and copying of this document. the notion of Moderation Factor has been introduced. The Moderation Factor is defined as the ratio between the actual traffic encountered in the BSC at its busy hour and the “theoretical” traffic figure. 8.DOC v 5 3DC 20003 0031 UZZZA 28/47 . However it has been noticed that the actual traffic encountered in a BSC is generally significantly lower than this sum. the load of the lost link is evenly and immediately distributed on all remaining links. if the MSC can also also support it. so that in case of failure of one link.2 SS7 channel on 2Mbit/s links (HSL) This option is available only with 9130 BSC Evolution. 8. A method for SS7 load estimation on the A-interface. is provided in Annex 1. SS7 links are traditionally dimensioned with 40% load (0.6 ERLANG per signaling channel) as soon as there are a minimum of four links configured. it is recommended to configure one SS7 link per A-ter link (with a maximum of 16 SS7 links).All rights reserved. This limitation is a GSM limitation. 8. In the receive direction.3. thus preventing loss of capacity. The SS7 load depends on the BHCA and other call mix parameters. So dimensioning SS7 links at 60% load is allowed with the Alcatel-Lucent BSS. the possibility to allow more than 0.6.4 ERLANG per link depends on the MSC strategy for load balancing in case of switchover.DOC v 5 3DC 20003 0031 UZZZA 29/47 . The SS7 load in this case is about 50% With less constraining traffic models.6 Signaling on A interface 8.6. it is possible: Ed MRD 03 Released DMCPTBE3. So in case of switchover due to the loss of one signaling link.2 for configuration rules.3 SS7 dimensioning for 9120 G2 BSC 1AA 00014 0004 (9007)A4 With the Alcatel-Lucent traffic model presented in Annex 1. and so cannot be extended. It becomes mandatory when 16 SS7 timeslots are not enough to convey the signaling traffic of the highest BSC configurations or in case of very demanding traffic models. 8. the switchover of one link onto another brings the total load of the remaining links below 80%. depending on capacity and call mix parameters.1 SS7 channels on 64 kbit/s time slots The number of SS7 64 kbit/s channels required depends on the traffic mix. This strategy allows the BSC to cope with SS7 signaling load up to 60% (0. The Alcatel-Lucent BSC (9120 and 9130) always balances the load on all signaling links in the BSCto-MSC direction.6. See section 8. use and communication of its contents not permitted without written authorization. There is a maximum of one SS7 64 kbit/s channel par A-ter link There is a maximum of 16 SS7 signaling channels per BSC (so 32 for rack-shared configuration of 9130 BSC Evolution). Passing on and copying of this document.4 ERLANG per signaling channel). he can use an external routing solution. then like above. Transport of A signalling over IP/MLPP/E1 on A-ter is not supported natively by the BSS.6. A Signalling over IP is mandatory when A Flex feature is used. In case the Operator wants to continue conveying A signalling over legacy E1 links. - Either to dimension the SS7 links at 40% load - Or to reduce the required number of SS7 links. the number of links is the sum of the links required for each BSC. 8. Ed MRD 03 Released DMCPTBE3. the method showed in Annex 1 can be followed to estimate exactly the number of links. BSC configuration BHCA SS7 links @ SS7 links @ 40% 60% 11 8 BSC-EV-200 64 800 BSC-EV-400 129 600 HSL 15 BSC-EV-600 194 400 HSL HSL BSC-EV-800 259 200 HSL HSL BSC-EV-1000 324 000 HSL HSL SS7 links for different BSC Evolution configurations and SS7 load Notes: For rack-shared configuration. 1AA 00014 0004 (9007)A4 When A Signalling over IP is used. with the Alcatel-Lucent traffic model. an external routing solution can be envisaged. the O&M link between the OMC-R and the BSC can only use the Ethernet connectivity of the BSC. use and communication of its contents not permitted without written authorization.4 SS7 dimensioning for 9130 BSC-Evolution The following table shows the number of links needed for SS7 dimensioning at 40% and 60% load. 8. for the Operator having already deployed a NGN core network. With less constraining parameters. In case the Operator wants to continue using IP/MLPP/E1 on Ater. Transmission over TDM (E1 timeslots or full E1 in case of High Speed Link (HSL)) is replaced by transmission over an IP network thanks to the Ethernet connectivity of the BSC Evolution.All rights reserved. Passing on and copying of this document. which already use SIGTRAN protocols for internal purpose.DOC v 5 3DC 20003 0031 UZZZA 30/47 . Legacy transport of A interface signalling using SS7 principles is replaced by SIGTRAN protocols. It is an alternative to HSL for high BSC configurations.7 A signaling over IP This alternative is available from B11 on the 9130 BSC Evolution. DOC v 5 3DC 20003 0031 UZZZA 31/47 .06 2. For a given BSS SW release.5 DL 0.04 1.Chunk header : 16 bytes For more details refer to [6]. they have to be confirmed upon platform tests completion. Ed MRD 03 Released DMCPTBE3.Alcatel-Lucent traffic model (by default the traffic model considered is very heavy. Passing on and copying of this document.27 2. BSC configuration BSC-EV-200 BSC-EV-400 BSC-EV-600 BSC-EV-800 BSC-EV-1000 UL 1.M3UA header : 36 bytes . The architecture of a BSS using A Signaling over IP is depicted in the figure below.65 2.62 3.SCTP header : 12 bytes . inducing 1AA 00014 0004 (9007)A4 high signalling load on A interface) .Ethernet header : 38 bytes . and depending on BSC configuration. use and communication of its contents not permitted without written authorization. A Signaling over IP The table below provides information on the A signaling over IP throughput at BSC Ethernet connector.IP header : 20 bytes .All rights reserved.93 1.88 3.5 2.18 A Signaling throughput (in Mbits/s) Hypothesis: . are used and enable other STM-1 types. Up to 4 STM-1 links can be connected (Optical interfaces.1 Connection to the G2 TC Each BSC rack must be connected to only one TC G2 rack. but mix of E1 and STM-1 connections is possible on A and Ater.2 Connection to the 9125 TC 9.1 Rules at BSC side It is possible to connect up to 24 BSC on one 9125 TC. 9.2.2 Rules at 9125 TC side E1 connectivity: On A-ter interface. the Operator can choose which A or A-ter links should be 1AA 00014 0004 (9007)A4 transported over STM-1. It is available for both A and A-ter interfaces.2. in mono-mode/short-haul type10). In case of a mixed configuration. One STM-1 link can contain up to 63 VC12 containers. Passing on and copying of this document. allowing for 100 % STM-1 connectivity. STM-1 connectivity: STM1 connectivity is available in the 9125 TC from B10 MR2 onwards. use and communication of its contents not permitted without written authorization. up to 192 E1 ports are available per TC rack (4 per MT120 board). and which of the links should be transported over E1 links. But one TC rack can be connected to several BSC racks. 9. called SFP (Small Form Factor Pluggable). 9. TRANSCODER DIMENSIONING RULES 9. It is also possible to connect one BSC to different TC racks. Please refer to the G2 TC product description [4] for more details. 10 Pluggable O/E converters. up to 48 E1 ports are available per TC rack (1 per MT120 board). Ed MRD 03 Released DMCPTBE3.All rights reserved. Each E1 link is transported transparently in one 2 Mbit/s VC12 container. On A interface.DOC v 5 3DC 20003 0031 UZZZA 32/47 . the other hand the A and A-ter interfaces of a same MLT120 board can be of different types. WB-AMR requires the “MT120-WB” TC board. Refer to the 9125 TC product description [5] for more details. for 1AA 00014 0004 (9007)A4 a smooth feature introduction according to AMR-WB MS penetration.If the O&M link to the OMC-R is not conveyed by the A-ter interface. it is possible to mix MT120 and MT120-WB in the transcoder. . 9.The only rule is that the four A interfaces of a same MT120 board must all be of the same type. See ref [5] for details. are implemented.3 Minimum number of A/A-ter links At least 2 A-ter links per BSC are required.4 Introduction of Wide Band AMR Only Codecs. which can be transported in 16Kbit/s time slots. On All rights reserved. Ed MRD 03 Released DMCPTBE3. This board can be plugged into already deployed G2 TC and 9125 TC.If the O&M link to the OMC-R is conveyed by the A-ter interface. Passing on and copying of this document.DOC v 5 3DC 20003 0031 UZZZA 33/47 . 9. When the MSC supports TC pools. each A-ter link needs to be connected to a minimum of one A interface link (total two A links). use and communication of its contents not permitted without written authorization. each A-ter link needs to be connected to 2 A interface links (total four A links). . Hence there is no impact on transmission dimensioning. One MFS is connected to one single OMC-R. The maximum number of active PDCH is given below: Ed MRD 03 Released DMCPTBE3. Passing on and copying of this document. depending on packet traffic.up 8 A-ter links .2.1 9135 MFS configurations rules The 9135 MFS (DS10) (*) can accommodate from 1 to 2 telecommunication sub-racks and house 32 GPU boards: 15 GPU boards plus 1 GPU board for redundancy per subrack. but in this case it will not be increased when adding a second sub-rack. but one GP(U) is connected to only one SGSN.DOC v 5 3DC 20003 0031 UZZZA 34/47 .2 9135 MFS 10. The maximum number of cells may be reached with only one sub-rack. These GPU boards can belong to different MFS subracks. 10. All the BSC connected to a given MFS must be connected to the same OMC-R as the MFS. 10.All rights reserved.1 Common rules for 9130 and 9135 MFS Each GP(U) board is connected to only one BSC. (*) MFS based AS800 is not supported from B11 onwards.2. But one BSC can be connected to up to 6 GP(U) board. One 9135 MFS can control up to 22 BSC. MFS DIMENSIONING RULES 10.Up to 8 Gb links 1AA 00014 0004 (9007)A4 One GPU can be configured with a maximum 264 cells. 10. One MFS can be connected to several SGSN. One MFS can manage up to 2000 cells. One MFS can be connected to BSCs themselves connected to different MSC. use and communication of its contents not permitted without written authorization.2 9135 MFS GPU capacity One GPU board can support up to 16 external links . The granularity is 1 GPU board. use and communication of its contents not permitted without written authorization.DOC v 5 3DC 20003 0031 UZZZA 35/47 . on the basis of the PS traffic model described in Annex 1. The GPU achievable throughput is highly dependant on the type of application. Max CS CS1 CS2 CS3 CS4 Max PDCH 240 240 216 192 Maximum GPRS PDCH per GPU Max EGPRS MCS Max PDCH MCS 1 MCS 2 MCS 3 MCS 4 MCS 5 MCS 6 MCS 7 MCS 8 MCS 9 220 208 204 192 176 164 132 112 104 Maximum EDGE PDCH per GPU The above numbers corresponds to the number of PDCH. which can be simultaneously active in the GPU. Passing on and copying of this document.3.1 9130 MFS configurations rules The 9130 MFS Evolution can house up to 21 GP boards (plus 1 GP board for redundancy) in 1 to 2 1AA 00014 0004 (9007)A4 telecommunication sub-racks Therefore one 9130 MFS can control up to 21 BSC. The achievable throughput depending on the application and for a mix of traffic are provided below. assuming all PDCH are using the same CS or MCS.3 9130 MFS Evolution 10. Capacity WEB WAP MMS DL Streaming Mix of traffic DL throughput (kbit/s) 900 130 540 1 480 620 UL throughput (kbit/s) 50 20 340 5 130 Table 20: Achievable throughput per GPU for GPRS users Capacity WEB WAP MMS DL Streaming Mix of traffic DL throughput (kbit/s) 1 100 130 650 2 000 700 UL throughput (kbit/s) 60 20 400 5 150 Achievable throughput per GPU for EDGE users 10.All rights reserved. Ed MRD 03 Released DMCPTBE3. In previous version of this document. the Stand-alone small with up to 8 GP / 16 E1 per GP was known as Rack-shared (Single). As this denomination can be misleading (No real rack sharing as there is only one MFS). contrary to the stand-alone large MFS.DOC v 5 3DC 20003 0031 UZZZA 36/47 . Ed MRD 03 Released DMCPTBE3. 1AA 00014 0004 (9007)A4 Note 1: Both maximum number of E1 and maximum number of GP for stand-alone MFS cannot be reached simultaneously. The operator has to make the following choice at commissioning11: 11 The choice has to be done at commissioning so as to allow extension without service interruption due to re- cabling and reloading of MFS configuration file. as illustrated by the next table B10 MFS configurations Stand-alone small MFS Number of ATCA shelves 1 2 2 Number of logical MFS (NE) 1 1 2 Maximum number of BSC 8/9 16/21 16 Maximum number of cells 4000 4000 8000 Number of LIU racks 1 1 2 Number of LIU boards for MFS 8 16 16 E1 connection available 128 256 256 Max GP (active) 8/9 16/21 16 See note 1 See note 1 1 1 16/12 16/12 GP standby Max E1 per GP (LIU board constraint) Stand-alone – Rack-shared large MFS MFS (double) See notes 1 & 2 See notes 1 & 2 2 16 Note 2 MFS Evolution configurations General notes: . Passing on and copying of this document. as a workaround to the limit of 12 E1 per GP for stand-alone configuration (limit removed from B10 MR2).All rights reserved. The 9130 MFS exist in several configurations. So each ATCA shelf contains both a duplicated switch.The rack-shared double MFS configuration has a lower capacity in number of GP than a large stand-alone MFS. the Rack-shared (Single) configuration is now presented as a variant of the Stand-alone small MFS. use and communication of its contents not permitted without written authorization. . .The rack-shared configurations were introduced in B9. but allows more flexibility for connecting each MFS to a distinct OMC-R (Workaround to the rule that all BSC of a same MFS shall be connected to a same OMC-R) Such configurations house two independent MFS. OMCP and a redundant GP. The maximum number of PDCH. which can be simultaneously established. is determined per GP board. One GP can handle up to 500 cells. 10. two 2 E1 ports are reserved for clock distribution. Each A-ter links carries up to 112 GCH (4 GCH per A-ter time slot. One GP board can support up to 16 external links: - up to 16 A-ter links - up to 8 Gb links The maximum number of A-ter E1 is determined as follows: . The maximum number of PDCH is indicated both for the configuration with 16. 12 or 10 A-ter links per GP. Max CS CS1 CS2 CS3 CS4 GP1 960 960 924 860 If up to 14 A-ter E1 per GP 960 960 924 860 If up to 13 A-ter E1 per GP 960 960 924 860 If up to 12 A-ter E1 per GP 960 960 924 816 If up to 10 A-ter E1 per GP 960 960 896 680 1AA 00014 0004 (9007)A4 If up to 16 A-ter E1 per 1 With Gb/IP only Ed MRD 03 Released DMCPTBE3. - 12 E1 with up to 9 GP for the first shelf and up to 21GP with two shelves. and removing those reserved for GSL or other purposes as described in chapter 6.4. use and communication of its contents not permitted without written authorization. . Note 2: Up to B10 MR1. E1 are not used to carry the Gb data. In case of MFS in centralized clock mode. so up to 12 or up to 16 A-ter E1 depending on MFS configuration. the E1 of one GP must be distributed between Gb and A-ter interface. - 16 E1 with up to 8 GP with one shelf and up to 16 GP with two shelves.DOC v 5 3DC 20003 0031 UZZZA 37/47 .All rights reserved.In case of Gb/IP. For determining the required number of Gb and A-ter E1 depending traffic. please refer to [6]. 14 . Passing on and copying of this document.13. It is recommended to have at least two Gb links for safety reason.2 9130 MFS GP capacity The number of available E1 connections per GP is determined according to the configuration as shown in above table .In case of Gb/Frame Relay. so all the E1 links connected to one GP can be used for A-ter purpose. so there remains a maximum of 10 or 14 E1 for A-ter interface depending on the MFS configuration.3. Passing on and copying of this document. The GP achievable throughput is highly dependant on the type of application.DOC v 5 3DC 20003 0031 UZZZA 38/47 . The achievable throughput depending on the application and for a mix of traffic are provided below. Capacity WEB DL throughput (kbit/s) UL throughput (kbit/s) 4 140 210 WAP 680 90 MMS 2 540 1 590 DL streaming 6 480 15 Mix of traffic 2 960 620 DL streaming 8 050 15 Mix of traffic 3 310 700 Achievable throughput per GP for GPRS users Capacity WEB DL throughput (kbit/s) UL throughput (kbit/s) 4 710 240 WAP 680 90 MMS 2 980 1 860 1AA 00014 0004 (9007)A4 Achievable throughput per GP for EDGE users 1 With Gb/IP only Ed MRD 03 Released DMCPTBE3. use and communication of its contents not permitted without written authorization.All rights reserved. assuming all PDCH are using the same CS or MCS. on the basis of the PS traffic model described in Annex 1. Maximum GPRS PDCH per GP Max EGPRS MCS MCS 1 MCS 2 MCS 3 MCS 4 MCS 5 MCS 6 MCS 7 MCS 8 MCS 9 If up to 16 A-ter E1 per GP1 840 816 824 800 744 720 512 432 396 If up to 14 A-ter E1 per GP 840 816 824 800 744 664 448 376 348 If up to 13 A-ter E1 per GP 840 816 824 800 744 616 416 348 324 If up to 12 A-ter E1 per GP 840 816 824 800 720 568 384 324 296 If up to 10 A-ter E1 per GP 840 816 824 744 600 472 320 268 248 Maximum EDGE PDCH per GP The above numbers corresponds to the number of PDCH. which can be simultaneously active in the GP. DOC v 5 3DC 20003 0031 UZZZA 39/47 . as well as an expected distribution of CS/MCS. use and communication of its contents not permitted without written authorization. 10. due to very long propagation delays. Each GPU or GP board requires at least one GSL channel.3 General considerations on PS traffic model In the Alcatel-Lucent traffic model. while using very little radio throughput.All rights reserved. For DL streaming. all packet users are considered active. 10. The GB/ Ater dimensioning must be adapted accordingly. Hence the maximum number of PDCH or throughput may not be reachable in such case. In reality it is possible to have a proportion of attached users.4 Number of GSL channels The GSL (GPRS signaling links) transports the signaling between the BSC and the MFS for PS services. who are only generating signalling. Passing on and copying of this document. the achievable throughput corresponds to what is possible at board level with maximum number of PDCH at very high CS/MCS. In this case specific dimensioning is required. Ed MRD 03 Released DMCPTBE3. it is recommended to have at least 2 GSL channels per GPU or GP board. With the PS traffic model provided in annex. For security reason. please refer to [6]. However in reality the bandwidth available on Gb interface must be taken into account. 2 GSL links per GPU or GP board is sufficient.3. There can be 0 or 1 GSL per A-ter link. Such users are taking CPU resources. For more details on GP dimensioning depending on PS traffic. except for the case of A-ter-PS carried over 1AA 00014 0004 (9007)A4 satellite links. There can be up to - 4 GSL per GPU board - 8 GSL per GP board - 24 GSL per BSC Evolution - 18 GSL per G2 BSC (due to max 18 A-ter links) The required number of GSL channels depends on the traffic. 7 283 7s Total bytes for 1888 one call (**) CS traffic model G2 BSC BSC Evolution 70 Paging/s 120 Paging/s CS paging on A interface (*) (*): Values corresponding to the maximum BSC configurations (448 TRX for the G2 BSC and 1000 TRX for the Evolution BSC). 11. Ed MRD 03 Released DMCPTBE3.4 381 4s 50s Internal Handover 2 41 - External Handover 1 199 - Location Update 3 228 4s IMSI Attach 0. The BSC can handle different call mixes.DOC v 5 3DC 20003 0031 UZZZA 40/47 . (**) Total bytes for one call is computed considering the average ratio and bytes per procedure. Passing on and copying of this document. G2 BSC: machine limits – BSC Evolution: results from the application of the traffic model. performance versus traffic mix can be committed only 1AA 00014 0004 (9007)A4 after BSC load test completion.5 228 4s MO SMS (PtP) 0.6 392 4s 50s MT Call 0. use and communication of its contents not permitted without written authorization. .All rights reserved.1 BSS traffic model for CS traffic: Mean holding time Average Bytes per ratio per Call procedure Events SDCCH TCH Attempt MO Call 0.The traffic mix presented here above is considered as a worst case. ANNEX 1: BSS STANDARD TRAFFIC MODEL 11.5 228 4s IMSI Detach 0. . If a Customer’s traffic mix is significantly different from the above Standard Traffic Model.For a given BSS SW release.3 362 7s MT SMS (PtP) 0. Alcatel-Lucent is prepared to study the possibility for the BSC to cope with it. All rights reserved. 2 Mbit/s (one HSL link) satisfay the requirements for a 4500 Erl BSC with the Alcatel-Lucent traffic model. 11.6) If the resulting number of links is above 16. Required SS7 throughput in kbit/s = BHCA /3600 x Total bytes for one call Attempt x 8 /1000 The required SS7 throughput is estimated in the MSC to BSS direction (worst case. because of paging load). it is possible to estimate the SS7 required throughput and corresponding number of SS7 links needed. Number of required channels at 64 kbit/s: • For 40% SS7 load: ROUNDUP (Required SS7 throughput / 64 x 0.2 SS7 LINK DIMENSIONNING With the total bytes for one call attempt from previous table and given BHCA. use and communication of its contents not permitted without written authorization. the second HSL being used for redundancy purpose.DOC v 5 3DC 20003 0031 UZZZA 41/47 . then SS7 on 2 Mbit/s link (HSL) is required. Passing on and copying of this document. 1AA 00014 0004 (9007)A4 Therefore two SS7 HSL are sufficient. Ed MRD 03 Released DMCPTBE3.4) • For 60% SS7 load: ROUNDUP (Required SS7 throughput / 64 x 0. Or the MS is attached when switched on. which means the packet call constitutes a burst of packets. The session is described by: The signaling phase description. Passing on and copying of this document. 11. There is some times during which the user is looking at the screen. The data load per session (page size). The instans of packet arrivals to network equipment A transaction t A packet service session First packet arrival to network equipment Last packet arrival to network equipment Typical characteristic of a packet service session For example a WEB session consists of the period during which a user is actively doing WEB browsing. which corresponds to idle periods between transactions. PDP context activation occurs at the beginning of each session. During a packet call several packets may be generated.All rights reserved. The user initiates the packet call when requesting information. use and communication of its contents not permitted without written authorization. a transaction corresponds to the download of a WEB page. The attachment procedure can be triggered: 1AA 00014 0004 (9007)A4 Either at the beginning of each session. Ed MRD 03 Released DMCPTBE3. During this session. The number of transactions per session.DOC v 5 3DC 20003 0031 UZZZA 42/47 . A GPRS traffic session is defined as the sequence of packet calls (or transaction). PDP context deactivation occurs at the end of each session.3 BSS traffic model for PS traffic The following traffic model is used as a reference to determine the capacity of the GP and GPU boards. The expected average packet size (IP-packet). for each application 1AA 00014 0004 (9007)A4 and for the mix of all users. With the delayed downlink TBF release feature1. FTP downloads or mail application.Additionally. Profile Percentage of subscribers for each profile WEB WAP MMS-D MMS-U DL streaming 5% 40% 25% 25% 5% Alcatel mix of profile for BSS The above data are used to determine the capacity of the GP and GPU boards. The cell update can be neglected because it occurs during a transfer and does not trigger additional TBF establishment. For simplification only periodic Routing area update is considered with default value of the 3GPP timer T3312 (= 54mn). a transaction can be identified to the time during which the downlink TBF is established. mobility management (Routing Area update and cell update) must be taken into All rights reserved. use and communication of its contents not permitted without written authorization. WAP. Ed MRD 03 Released DMCPTBE3. account. 1 It is assumed that the DL TBF is maintained as long as an uplink TBF is established taking into account the addition of T_network_response_time. then adding the signaling for mobility and PDP context activation.DOC v 5 3DC 20003 0031 UZZZA 43/47 . even if no data are sent on the downlink. Passing on and copying of this document. A transaction can be seen as the period during which resources will be allocated to serve a burst of packets. number of UL/DL PDU. For each type of service the transaction and session profile is specific. MMS. we can describe the average user behavior at the busy hour for each application. average PDU size) which vary for each application. From the session description is characterized for each type of application as follows: Session description (application level) WEB WAP MMS-D MMS-U DL streaming PS paging 0 0 1 0 0 Number of transactions per session 5 7 1 1 1 Average transaction size (Kbytes) 50 1 50 30 300 1000 1000 1500 1500 1500 Average packet size for control message (bytes) 40 40 40 40 40 User data load session DL (Kbytes) User data load /session UL (Kbytes) 250 0 7 0 50 0 0 30 300 0 Average packet size for user data (bytes) PS Session description for all profiles With some additional hypothesis at transaction level not detailed here (number of TBF establishment. The combination of the transaction and session description allows producing significant parameters at PCU level. Then the average traffic model can be based on proportion of each application. Streaming. The Alcatel-Lucent traffic model considers the following main applications: WEB browsing. and we shall use the notation “roundup (x)” when a value x is to be rounded up to the next higher integer. For high signaling load the formula roundup (Number of TRX/ 2) applies. TRX per BTS 1 2 3 4 5 6 7 8 9 10 11 12 A-bis TS for RSL +OML 1 1 2 1 2 2 3 2 3 3 4 3 TRX per BTS 13 14 15 16 17 18 19 20 21 22 23 24 A-bis TS for RSL +OML 4 4 5 4 5 5 6 5 6 6 7 6 1AA 00014 0004 (9007)A4 Number of A-bis TS required for statistical multiplexing 64 Kbit/s. Passing on and copying of this document. 12. For statistical multiplexing on 64 kbit/s.DOC v 5 3DC 20003 0031 UZZZA 44/47 . normal signaling load.2 and 3. taking into account the fact that 3 RSL cannot be carried by one single A-bis TS (it requires 2 TS=The minimum number of A-bis TS required for signaling with statistical multiplexing on 64 Kbit/s depending on the number of TRX is provided in the table below (case normal signaling load). For G2 sectored BTS. Ed MRD 03 Released DMCPTBE3. Trafic (n TRX) OML if 9100 BTS OML if G2 BTS (*) RSL if 9100 BTS RSL if G2-BTS (*) Without Signaling Multiplexing Static-Signaling Multiplexing 2n (2 per TRX) 1 per BTS 1 per Sector 1 per TRX 2n (2 per TRX) 1 per BTS 1 per Sector Roundup (n/4) Roundup (i/4)+ Roundup (j/4)+ Roundup (k/4) 1 per TRX StatisticalSignaling Multiplexing-64k 2n (2 per TRX) 0 Not applicable See below Not applicable StatisticalSignaling Multiplexing-16k 2n (2 per TRX) 0 Not applicable 0 Not applicable Number of A-bis time-slots required according to the different Signaling Multiplexing schemes (*): G2 BTS are no more supported from B11 release.1 Number of time-slots required with the different Signaling Multiplexing schemes The table below gives the number of 64 kbit/s time-slots required with the different Signaling Multiplexing schemes. use and communication of its contents not permitted without written authorization. j and k the number of TRX in sector 1. we shall note i. ANNEX 2: A-BIS INTERFACE CONFIGURATION 12.All rights reserved. a simple formula is not possible. The BTS is assumed to have n TRX in total all working in Full-Rate mode. Ed MRD 03 Released DMCPTBE3.All rights reserved. one 9100 BTS with 3x1 TRX requires: 3x2 = 6 time-slots. High Signaling load: 3x4x2 + 3 = 30 time-slots. . it is possible to connect 7 of such BTSs with only one A-bis PCM.With Static Multiplexing.With Statistical Multiplexing 16k. Typical cases where Signaling Multiplexing is very advantageous . a sectored site with 3 x G2 BTS having 4 TRX requires: 3x[1+ 4x2+ roundup (4 / 4)] = 30 time-slots. . it is possible to connect 2 such sites with only one A-bis PCM. one 9110 Micro-BTS with 2 TRX in full Rate mode requires: 2x2 = 4 time-slots.With Statistical Multiplexing 16k. Hence. it is possible to connect this site with only one A-bis PCM (except if Closed Loop with TS0 transparency) . . High signaling load: 3x2x2 + 3 = 15 time-slots. one 9100 BTS having 3x2 TRX requires: Normal signaling load: 3x2x2 + 2 = 14 time-slots. Passing on and copying of this document. Hence.DOC v 5 3DC 20003 0031 UZZZA 45/47 . use and communication of its contents not permitted without written authorization. Hence.With Statistical Multiplexing 64k. Hence. one 9100 BTS having 3x4 TRX requires Normal signaling load: 3x4x2 + 3 = 27 time-slots. it is possible to connect 5 such sites with only one A-bis PCM (if open chain or 1AA 00014 0004 (9007)A4 closed loop with TS0 usage).With Statistical Multiplexing 64k. A secondary link may terminate a daisy chain. Passing on and copying of this document. then the Extra A-bis timeslots. but it is possible to limit the number of TRX in the first A-bis link. In addition.2 Configurations with 2 A-bis links For large BTS configurations. the first A-bis link is filled up as much as possible. for example in anticipation of a further TRX extension of the BTS. A parameter MAX_EXTRA_TS_PRIMARY defines the number of extra A-bis timeslots dedicated to packet on the primary link. Two parameters MAX_FR_TRE_PRIMARY and MAX_DR_TRE_PRIMARY define the maximum 1AA 00014 0004 (9007)A4 number of TRX of a BTS. They may be connected to different A-Bis TSUs.DOC v 5 3DC 20003 0031 UZZZA 46/47 . a single E1 is already almost full with pure Circuit Switched traffic. This allows the Operator keeping some free timeslots on the primary link. BSC Primary Abis EVOLIUM BTS Secondary Abis Primary Abis EVOLIUM BTS Secondary Abis BTS BTS Examples of A-bis topology Note concerning the G2 BSC: There is no constraint about the position of the primary and secondary links in the BSC. then the Full Rate TRX. Ed MRD 03 Released DMCPTBE3. the TWIN TRX gives the opportunity to put more TRX than 12 TRX inside a single BTS rack. To support EDGE in such large BTS. use and communication of its contents not permitted without written authorization. it is also possible to configure a secondary A-bis link with basic A-bis nibbles. extra timeslots can be configured on a second A-bis link. By default. 12. and even different BSC racks.All rights reserved. The Dual Rate TRX are mapped first. The following figure depicts examples of A-bis topology. which are mapped on the first A-bis link (respectively for Full Rate and Dual Rate). For this purpose. A primary link is directly connected from BSC to BTS. The OML of a BTS is always mapped on the first A-bis link. use and communication of its contents not permitted without written authorization. Second A-bis RSL 9-12 TRX9 TRX9 TRX10 TRX10 TRX11 TRX11 TRX12 TRX12 RSL 13-16 TRX13 TRX13 TRX14 TRX14 TRX15 TRX15 TRX16 TRX16 First A-bis OML+RSL1-4 TRX1 TRX1 TRX2 TRX2 TRX3 TRX3 TRX4 TRX4 RSL 5-8 TRX5 TRX5 TRX6 TRX6 TRX7 TRX7 TRX8 TRX8 MAX_FR_TRE_PRIMARY= 12 MAX_FR_TRE_PRIMARY= 8 This second option may be used for optimizing the filling of G2 BSC TSU. The TCH and the RSL of a TRX are grouped on the same A-bis link.All rights reserved. In the first case.DOC v 5 3DC 20003 0031 UZZZA 47/47 . which carries the multiplexed RSL. MAX_FR_TRE_PRIMARY is set to 12 (default value). while on the second case Second A-bis RSL 13-16 TRX13 TRX13 TRX14 TRX14 TRX15 TRX15 TRX16 TRX16 First A-bis OML+RSL1-4 TRX1 TRX1 TRX2 TRX2 TRX3 TRX3 TRX4 TRX4 RSL 5-8 TRX5 TRX5 TRX6 TRX6 TRX7 TRX7 TRX8 TRX8 RSL 9-12 TRX9 TRX9 TRX10 TRX10 TRX11 TRX11 TRX12 TRX12 MAX_FR_TRE_PRIMARY is limited to 8. Passing on and copying of this document. The following figure provides 2 examples for a BTS with 16 Full Rate TRX. in case of RSL multiplexing. 1AA 00014 0004 (9007)A4 End of Document Ed MRD 03 Released DMCPTBE3. the TCH belonging to the TRX of which the RSL are multiplexed together are mapped on the same A-bis links. as well as the A-bis time slot. Furthermore.
Report "Dimensioning Rules for CS and PS Traffic.pdf"