02 RN20092EN14GLN0 Site Solutions Hardware

RG10(BSS) for Network PlannersIntegrated IP card for BSC3i and TCSM3i_BSS21157
PCU2 HW Evolution and Asymmetrical PCU HW configuration_BSS21226
Radio Network Performance
SDCCH and PS Data Channels on DFCA TRX_BSS21161
Downlink Dual Carrier_BSS21228
Improvement in Operability
Flexi EDGE Dual TRX Automatic Power Down_BSS20984
* © Nokia Siemens Networks RN20092EN14GLN0
Benefits
Architecture
Site Solution Hardware Support
Circuit-switched capacity for voice 18000 Erlangs
Packet data capacity for EDGE evolution up to 30720 Abis links (16kbit/s)
3000 TRXs and 3000 BTS sectors/sites in one cabinet
Scalable in 6 HW capacity steps (BCSUs) from 500 TRX to 3000 TRX, license step one TRX
New support of IP/Ethernet for all interfaces
Flexible transmission types (E1/T1, STM-1/OC-3, IP/Ethernet)
Very high footprint efficiency
Excellent power consumption efficiency
Supervising of GSWB, executing RRM functions, internal traffic handling by Ethernet Message Bus (EMB) and LAN Switching Units (SWUs)
Operation and Maintenance Unit (OMU)
Supporting O&M for Flexi BSC incl. storage devices (interfaces to user/OMC/transmission/peripherals, alarm collection and indications, system configuration/management, BSC3i maintenance/administration, LAN topology management)
Bit-oriented Group Switch (GSWB)
Exchange Terminal (ET)
Connecting of transmission systems (E1/T1, STM1/OC3, PWE3) to GSWB; several ET types are possible within Flexi BSC: ET16, ETS2, ETIP
Base Station Controlling and Signalling Unit (BCSU)
Handling of signalling traffic (LAPD, SS7) incl. PCU
Flexi BSC Configuration Steps
Overview on Flexi BSC capacity
The following table presents the main capacity figures of the Flexi BSC
#TRX per BSC
6
3000
30
30720
24000
0
16
16
12
12
6
12
5952
50
16
8
(*1): #LAPD links achievable with “low capacity” SS7 links. Therefore in 3000 TRX conf. SS7 over IP (SIGTRAN) is recommended.
(*2): #controllable PCM lines does not depend on #BCSU
SET: SDH Exchange Terminal
PCU functionality in Flexi BSC can be realized by both:
PCU2-E, a new plug in unit offering significant capacity enhancements
PCU2-D,
Each BCSU can be equipped with up to 5 PCU
BCSU can have a mixture of PCU2-D/PCU2-E
With Asymmetric PCU configuration feature all BCSUs within one BSC do not need identical PCU configurations
PCU2-D comprises 2 logical PCU, each logical PCU can handle up to 256 Abis PS channels@16
PCU2-E comprises 1 logical PCU, it can handle up to 1024 Abis PS channels@16.
Dimensioning concept same as with BSC3i:
All static and dynamic limits are checked against the corresponding values determined per planning area
The basic formula is used to calculate the number of BSCs in a given area
The initial BSC utilization level is considered to leave capacity for future extensions and traffic growth
Flexi BSC offers high scalability and configuration variety:
In a given BSC the following items are calculated
The number required of BCSUs
The number of required PCUs
The number and types of the interface units/ports
Working BCSU is needed for each 500 TRXs
Every BCSU is equipped with the number of AS7-D units sufficient to handle signalling traffic produced by 500 TRX
Also other units (power supply, CPU, memory) are always installed and do not need to be computed
Apart from this, BCSU can be equipped with up to 5 PCUs
The number of working BCSU per Flexi BSC can be computed by formula below:
Regardless of the amount of working BCSU an extra spare one is always needed for redundancy
N+1 redundancy principle applies for the BCSUs
Dimensioning
PCU2-E
PCU2-E has several static limits (#Abis channels, #TRX, #BTS, #segments, #EDAPs, …)
(For details about PCU2-E static limits please refer to product documentation)
Usually the most critical parameter in PCU dimensioning is the number of Abis channels that can be managed by PCU
PCU2-E serves 1024 Abis channels@16 kbps
PCU2-D serves 256 Abis channels@16 kbps
The number of PCU can be computed by means of the formula below:
Dimensioning
ET
The number of Exchange Terminals (of given type) depend on how many PCM lines is terminated in Flexi BSC and what connectivity configuration has been chosen
The number of PCM lines can be computed by means of the formula below:
The next step is to decide which PCM lines will be connected to ET16, ETS2 and ETIP and to compute the required amount of PIU and cartridges to be installed
Then the number of particular PIU can be computed as follows (ETSI standard):
Please note that the actual number of ETS2 PIU depends on the number of required SET and number of optical interfaces activated per ETS2 (1 or 2 optical interfaces may be active):
1 optical interface per ETS2 active:
2 optical interfaces per ETS2 active:
Dimensioning
ET
Benefits
Benefits
Ethernet based transmission networks are cheaper that E1/T1 networks comparing the same bandwidths
At the same time, more and more transport resources are expected to be needed due to:
Availability of services which leads to increase in data rates and in the amount of transport resources
Collaboration on the same site base station operating in different technologies (e.g. GERAN, UTRAN )
Exchange Terminal for IP (ETIP) is fully integrated with the existing HW platform
ETIP (ETIP1-A) is designed in such a way that allows to be used instead of ETS2 or ET16,
Extends BSC3i/TCSM3i products flexibility and gives operator many new configuration possibilities
Any mixture of all S14 compatible Exchange Terminals is fully allowed
All these reasons cause that IP over Ethernet BSS interfaces are supposed to be the most efficient realization of transport network in GERAN
Integrated IP card for BSC3i and TCSM3i
ETIP1-A plug in unit
126 E1 / 168 T1 per ETIP1-A (in BSC3i)
128 E1/T1 per ETIP1-A (in TCSM3i)
512 different WS (Pseudo Wires)
512 different PSN tunnels
FastE: mainly to be used for local O&M interface
GigE: mainly to be used for PSN interface
PSN: Packet Switched Network
Functionality
TDM links can be replaced by IP over Ethernet links
Mapping of TDM traffic into IP packets possible thanks to PWE3 (Pseudo Wire Emulation)
PWE3 is a standardized mechanism which emulates the essential attributes of a service into Packet Switched Network (PSN).
Different services can be emulated by PWE3 with CESoPSN functionality (i.e.PWE3 of TDM traffic )
IP solution is applicable for Flexi BSC, BSC3i, TCSM3i and FlexiEDGE BTS products
PWE for other elements can be implemented by additional products e.g. hiD3105/3140HD.
PWE3 realization in BSS: CESoPSN
CESoPSN functionality
Circuit Emulation Service over PSN performs the following activities:
The TDM bit stream is segmented according to the user specified Time Slot Set (TSS)
bits transmitted by indicated PCM TS in subsequent TDM frames
Headers are added to each segment to form a manageable packet (encapsulation)
Packets are forwarded to the PSN tunnel and transmitted to its destination over Ethernet network
At destination, the original bit stream is reconstructed by removing headers, concatenating frames and regenerating the timing
Ch2
Ch24
payload
header
3 TDM frames mapped
Ref. P. Spennemann, Internal Ethernet/IP Interfaces for BSS
Feature Request Sheet, FRS 94060, version 2.0, May 2007
Number of ETIP are needed to map the desired TDM traffic into a PSN using Ethernet links with chosen bandwidth (FE vs. GE) . The following dimensioning aspects are:
Decide/choose which particular lines shall be mapped to a PSN
Define PWs (from TSS) for each PCM line to be mapped to a PSN
Define how many TDM frames shall be multiplexed within particular CESoPSN packets
Compute a bandwidth required by each and every PW
Compute the number of required ETIP1-A
BSC3i can have mixture of traditional TDM lines (ET16, ETS2) and PW lines (ETIP)
Planning and dimensioning aspects
The number of consecutive TDM frames per CESoPSN packet (Nf)
The time slot set i.e. the number of TSL from the original E1/T1 (TSS)
Use of VLAN (CESoPSN header 74 octets with VLAN and 70 octets without VLAN)
Required Ethernet bandwidth:
TS1
TS2
TS3
TS4
TS5
TS6
TS29
µ
s
TSx
2 frames multiplexed, packetization time of 2*125μs = 250 μs
Packet
Header
126 E1 lines to be mapped
1 PW per E1 line (each TSS composed of 31 TSs)
8 TDM frames per packet
CESoPSN header length of 74 bytes (VLAN is enabled)
Gigabit Ethernet and Fast Ethernet links shall be checked
Calculations:
packetization latency = 125 · Nf = 1000 μs (cf. eq. 2) => will be needed for time budget
payload = 8 * TSS * Nf = 1984 bits (cf. eq. 2) => 248 bytes; payload size acceptable
header = 8 * header_length = 592 bits (cf. eq. 2)
BW / PW = (1984 + 592) / 1000 = 2.576 Mbit/s (cf. eq. 1)
OHF = (1984 + 592) / 1984 = 1.29 29% (cf. eq. 4)
BW / PSN = 2.576 * 126 = 324.58 Mbit/s (cf. eq. 7)
GE link load = 324.58 / 1000 = 32.5% => all 126 E1 can be served by 1 ETIP
FE link load = 324.58 / 100 = 324.6 % => not possible!!!
With FE, 5 ETIP would be needed to handle 126 E1
126 E1 can be handled by 1 ETS2 (with 2 optical interfaces)
OHF : Off Hook Factor
Impact on implementation planning
Stand-alone TCSM3i has the following characteristics
Comprises of 1…6 TC2C cartridges in a single Transcoder Cabinet
Each TC2C houses 2 TR3E/TR3A PIUs
One TC2C cartridge can house two extension steps
One TC2C cartridge consist of up to 16 TR3E/TR3A units each up to 120 channels plus selected interface cards
Each TR3x has the following transcoding capacity:
TR3E: 960 TCH ETSI (8 E1 Ater lines)
TR3A: 768 TCH ANSI (8 T1 Ater lines)
Fully equipped TCSM3i can support:
6 TC2C × 2 TR3E × 960 = 11520 TCH ETSI
6 TC2C × 2 TR3A × 768 = 9216 TCH ANSI
6 TC2C × 2 TR3E × 8 Ater lines = 96 E1/T1 Ater 384 E1/T1 A-IF
up to 24 BSC can be connected to a single TCSM3i cabinet
Implementation of CESoPSN in TCSM3i
4 (active + spare) ETIP1-A can be installed in TCSM3i:
1 ETIP is used to handle Ater interface
3 ETIP are used to handle A interface, one ETIP can serve 2 (adjacent) TC2C
If the whole Ater is over IP the Ater ETIP in TCSM3i has to be configured as a synch master and an ETIP in the BSC as a synch slave.
Ref. P. Koski, M. Saukko, H. Tervonen, J. Toivinen,
PWE Transport Support in BSC3i and TCSM3i,
Requirements Specification, BSS21157, version 1.1.0, January 2008
Impact on implementation planning
Redundancy implementation concept are:
HW protection (N+N, active PIU has its own spare one)
Line protection (each board has two individual Ethernet interfaces while only one of them is active at the time)
IP addressing
IP addresses of the devices installed in FlexiBTS, BSC3i, TCSM3i are used during creation of PSN tunnel and its PWs: any mismatch is to be avoided
PCU2 HW Evolution and Asymmetrical PCU HW configuration
BSS14 for Network Planners
Benefits
Modified parameters, new alarms
Benefits
PCU related S14 features are expected to bring the following benefits
PCU2-E
Allows to increase packet data capacity within the same space
Optimized for Flexi BSC
Supports higher user peak rates
Better Gb link utilization. More cells per PCU gives better multiplexing gain in Gb.
Asymmetrical PCU HW configuration
Less PCU plug in units needed with the feature
Its benefit can be immediately seen in the scenarios like:
PCU capacity extension (in a single BCSU):
user needs to add only 1 single PCU to the BCSU where insufficient PCU capacity is observed
TRX capacity extension:
user needs to add another BCSU (without or with minimum PCU configuration)
Various amount of PCUs in different BCSU
PCU2 HW Evolution and Asymmetrical …
Benefits of PCU2-E
PCU2-E can also be used in the BSC3i 660 and BSC3i 1000/2000
Performance improvement is a prime reason to install PCU2-E in BSC3i types
Mixture of PCU2-E and PCU2-D is possible within BSC3i
Due to different internal structure in BSC3i and Flexi BSC the PCU2-E can reach half of its max possible capacity in when used in BSC3i 660/1000/2000
PCU2-E can handle up to 512 Abis channels in BSC3i 660/1000/2000
PCU2-E capacity
PCU2-E capacity is collected in the table below together with the respective values of PCU2-D for comparison
The capacities below are achievable per logical PCU in Flexi BSC
Parameter
PCU2-E
PCU2-D
1
2
1024
256
#EDAP
60
16
#BCF
384
Note: PCU2-D capacity figures are maintained in RG10 in comparison to S13 ones
128
Gb interface capacity for PCU2-E and PCU2-D
Overall, applicable for both PCU2-E / PCU2-D
Max Gb throughput can be reached with more than 1 FRL
Gb over FR: capacity of the Frame Relay links may limit the PCU throughput
Gb over IP: Gb connectivity does not limit the PCU throughput
Parameter
PCU2-E
PCU2-D
Total rate of FRLs / logical PCU
128 x 64 kbps
32 x 64 kbps
8 Mbps (128 TSL x 64 kbps)
2 Mbps (32 TSL x 64 kbps)
16 FRL/NS-VC
4 FRL/NS-VC
Possible configuration of PCU2-E
PCU2-E can be installed in Flexi BSC and any BSC3i but certain additional rules exist
PCU2-E can be installed neither in BSCi nor in BSC2i
There are 2 rules to be considered when using PCU2-E in BSC3i 660/1000/2000
Limited number of PCU slots in BCSU can host PCU2-E due to limitations of power supply and cooling systems
512 Abis channels can be reached due to connectivity implementation in BSC3i 660/1000/2000
BSC type
BSC3i 660
BSC3i 1000
BSC3i 2000
Flexi BSC
max #PCU2-E
per BCSU
~ 98 Mbps
~204 Mbps
~ 409 Mbps
~ 491 Mbps
Mixed PCU configuration
Different amount of PCUs in different BCSUs of the same BSC or different PCU HW variants in the same slots of different BCSUs
‘mixed PCU configuration’ is possible however some restrictions exist, i.e. the following mixtures are allowed within the same BCSU track of different BCSU
PCU, PCU-S, PCU-T, PCU2-U, empty slot
PCU-B, PCU2-D, empty slot
PCU2-E, empty slot
Mixed PCU configuration in such context is a new functionality that leads to “asymmetrical” PCU configuration
Asymmetrical PCU configuration is available as a separate RG10 feature
Before the feature:
Each BCSU in the BSC is equipped with the same PCU configuration (number of PCUs and their type)
For e.g. let’s assume a BSC3i 2000 equipped with 10 (active) BCSUs and 1 PCU in each BCSU
Let’s say that 1 out of 10 BCSUs needs another PCU to be installed (due to PS traffic)
To do so, each and every BCSU would need to have second PCU installed
10 extra PCUs are needed in case of fully equipped BSC3i 2000 to add 1 PCU in 1 BCSU
Asymmetrical PCU configuration
With the feature:
PCU can be installed and activated according to actual traffic needs with granularity 1 in every BCSU separately
Each active BCSU can have different number of PCUs (depending on actual traffic requirements), i.e. it may happen that some BCSU have no PCU units while the other ones have some PCU installed
Different PCU types can be mixed in the same BSC/BCSU (restrictions concerning the same BCSU track exist -> see previous slide)
BCSU which is marked as primary spare must
be equipped with the number of PCU sufficient to replace any of the active BCSU
PCU2 HW and SW Activation in S14
PCU2-E HW is installed according traffic requirements
PCU2-E SW is activated according traffic requirements
In minimum one PCU2-E HW unit + one PCU2-E HW unit for spare BCSU
In maximum four PCU2 BSW licenses per one PCU2-E HW plug-in unit
One PCU2 BSW license = 256 Abis channels (16 kbit/s)
Example :
1 + 1 PCU2-E HW units + one PCU2 BSW license
For E.g. with Flexi BSC and with Asymmetrical PCU HW Configuration
PCU2-E HW
PCU2-E HW
PCU2-E HW
PCU2 BSW
PCU2 BSW
PCU2-E HW
PCU2 BSW
PCU2 BSW
Spare BCSU
PCU2 BSW
PCU2 BSW
PCU2 BSW
PCU2 BSW
PCU2 BSW
PCU2 BSW
PCU2 BSW
PCU2 BSW
Overall PCU HW requirements for BSS14
All existing PCU units (PCU1, PCU2) could still be used with the basic S14 SW release
All new packet data related application SW features would require PCU2
Impact of introduction of PCU2-E on PCU dimensioning
Dimensioning concept does not need to be modified
All static limits must be checked against the corresponding values determined per BSC (planning area)
Utilization rate should be additionally taken into account
The basic formula used for PCU dimensioning is
No new parameters
Modified parameters: only ranges of those parameters that are explicitly dependent on modified static limits should be subject to modification, e.g. new PCU variant (PCU2-E) must be configurable in addition to former types
Parameter name (abbreviation)
Description
Plug-in Unit Type (piuType)
Range: 276 (pcu_c), 365 (pcu_s_c), 379 (pcu_t_c), 398 (pcu2_u_c), 979 (pcu_b_c), 985 (pcu2_d_c), 995 (pcu2_e_c), 1023 (no_piu_type_info_c) Default: 1023
PCU plug-in unit type. The attribute describes the PCU HW variant.
PCU
Range: 0…479 Step: 1 Default: -
Bearer channel identifier. The attribute allows to define the bearer channel ID. Note! Range: 0..95 for BSC3i 660 0..399 for BSC3i 2000 0..479 for BSC3i 3000 (6 BCSU/BSC × 5 PCU2-E/BSCU × 16 FRLorNSVC/PCU) 0..63 for other BSCs
NSVC, FRBC
Counters and alarms
PCU2-E requires no new counters nor measurements (apart from FRL measurement), it does not affect functional triggering points either)
only the amount of FRL measurements is extended due to increase in the number of FRL supported
No new alarms are introduced due to PCU2-E
only the amount of alarms (since the alarm count parameter is generally scaled according to the number of object instances raising the alarm) is to be extended (e.g. EGPRS DYNAMIC ABIS POOL FAILURE from 16 to 60 objects)
New alarms related to ‘Asymmetrical PCU configuration’
primary_spare_bcsu_missing_a: PCU configuration of BSC is asymmetrical and primary spare BCSU unit definition is missing
primary_spare_bcsu_invalid_a: Primary spare BCSU unit PCU configuration is invalid. Primary spare BCSU unit can not replace all BCSUs
NSVC: Network Service Virtual Connection

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02 RN20092EN14GLN0 Site Solutions Hardware