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1 BASIC BSC KNOWLEDGE
1.1 MXBSC HW overview
1.1.1 General concept:
1.1.1.1 ATCA
Advanced Telecom Computing Architecture, or AdvancedTCA(ATCA) is a series of industrystandard specifications for the next generation of carrier grade communications equipment. Asthe largest specification effort in PICMG's history and with more than 100 companiesparticipating, AdvancedTCA incorporates the latest trends in high speed interconnecttechnologies, next generation processors, and improved reliability, manageability andserviceability, resulting in a new blade (board) and chassis (shelf) form factor optimized for
communications. AdvancedTCA provides standardized platform architecture for carrier-gradetelecommunication applications, with support for carrier-grade features such as NEBS, ETSI, and99.999% availability.
The PICMG 3.X specification is intended to define open architecture modular computingcomponents that can be quickly integrated to deploy high performance services solutions. InPICMIG 3.X document, it presents base requirements:
- Mechanicals
- System Management
- Power Distribution
- Power Connector Zone (for Dual -48 VDC power to each Slot)
- Rear I/O Access Zone
- Data Transport Connector Zone (for System management and switching fabric interconnect)
- Shelf Thermal Dissipation
- Regulatory Guidelines
In one word, ATCA (based on PICMIG specification) have already provided lot of HW relatedfeatures for telecom product. It saves the effort for HW design.
1.1.1.2 IPMI
In addition to the Gigabit Ethernet switching function and to the TDM switching over Ethernetfunction, another key function of the MXBSC is the implementation and use of ATCA standardsfor the low level management of the modules at the shelf level: the IPMI. IPMI is used to controlall the ATCA HW entity.
This interface is implemented in the ATCA middleplane by two redundant IPM busses (IPMB),which interconnect all the FRUs of a shelf together.
The figure below shows the principle of IPMI implementation in an ATCA shelf.
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SYSTEM MANAGER
Figure 1 General IPMI implementation in an ATCA shelf
1.1.1.3 High Availability
MXBSC is Carry Grade Equipment. In case of failure, the system must be able to continueprocessing the same amount of users, after a service interruption of less than 30 seconds.When a software or hardware component is unique for the whole system, redundantbehaviour shall be used, allowing keeping the stable calls.
Maintenance Reason Protection
Hardware failure N+1 hardware redundancy
Recovery of faults of centralized units (1+1 redundancy, audit,)
Software failure Data protection and software restart without losing stable calls
New software release Future target: keep calls in case of minor software releasechange (same processing as for software failures)
Table 1: Requirements for a Five 9s System
Board EPS(EquipmentProtection Switching)
Manager
SSW 1+1 ATCA
OMCP 1+1 BSC+MXPF SW
CCP N+1 BSC+MXPF SW
TP GSM 1+1 BSC+MXPF SW
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SMM 1+1 ATCA
1.1.2
SSW(duplicated)
CCP1
CCP6
OMCP1 OMCP2
TP1
TP2
External Ethernet Links
LIU1
16E1LIU16R
adioNetworklinks
16E1
MUX1
MUX2
1.1.3
1.1.4
1.1.5 MXBSC Physical architecture
The following figure shows the general hardware architecture of the MXBSC:
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1.1.6
13
11
9 7 5 3 1 2 4 6 8 10
12
14
SSW
SSW
OMC
P
OMC
P
TPG
SM
CCP
CCP
CCP
CCP
TPG
SM
1U
8U
3U
12 -148 -104 - 61 - 25 - 39 - 713 - 11
1413121110987654321Physical address
logical address
CCP
EMPT
Y
EMPT
Y
C
CP
Function block Architecture
PEM
LIU
LIU
LIU
LIU
LIU
LIU
LIU
LIU
MUX
MUX
LIU
LIU
LIU
LIU
LIU
LIU
LIU
LIU
PEM
External E1 links (16 x sub -D 68 pins connectors)
1 GbE links (2 x RJ45 connectors) 48 or 60V DC 48 or 60V DC
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TPW
CCP1
CCPP
TPP
CCPN
SSWW
SSWP
OMCPW
OMCPP
1 Gigabit Ethernet - ATCA Base Interface
E1 Termination Shelf
External E1 Links
O&M + TELECOM
NE1oE
1.1.7 Process mapping
Following lists the main characteristics of MxBSC software.- Redundant user plane and control plane- Function splitting between user plane and control plane.- Application process communication is developed based on redundant TCP/IP.- More centralizing on application processing and transmission processing.
CM
- PRV-O
V-DTC TCH-RM
Figure 2: Processes Mapping on OMCP.
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Platform service
Interthreads Communication Bus
Init/SWSUP
CPI
TCUTCU
TCUV-TCU
TCUV-TCU
V-TCUV-TCU
DTCDTC
DTCDTC
DTCDTC
DTC
DTCV-DTC
CMW
CCP
Figure 3: Process mapping on CCP
Platform service
Interthread comm. bus
Init/SWSUP
CPI
TP-SS7 SLH
CMWP
TP-Main
Interthread comm. bus
Configuration
Handler
FaultManag
erHandler
HDLCLAPD
Handler
Perf.Param.Handler
R/WBitsAlarmOctet
Handler
HDLCMLPPPHandler
QMUXHandler
TDMHandlerMatrixFramer
s
Figure 4: Process Mapping on TPGSM
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E1 Abis E1 not used
E1 Ater CS E1 Ater PS
LIU 1 L IU 2 L IU 3 L IU 4 LIU 5 LIU 6 LIU 7 L IU 8 L IU 9 L IU 10 L IU 11 LIU 12 LIU 13 LIU 14 LIU 15 LIU 16
1 1 17 33 49 65 81 97 113 129 145 161 41 31 21 2 1
2 2 18 34 50 66 82 98 114 130 146 162 42 32 22 4 3
3 3 19 35 51 67 83 99 115 131 147 163 43 33 23 6 5
4 4 20 36 52 68 84 100 116 132 148 164 44 34 24 8 7
5 5 21 37 53 69 85 101 117 133 149 165 45 35 25 10 9
6 6 22 38 54 70 86 102 118 134 150 166 46 36 26 12 11
7 7 23 39 55 71 87 103 119 135 151 167 47 37 27 14 13
8 8 24 40 56 72 88 104 120 136 152 168 48 38 28 16 15
9 9 25 41 57 73 89 105 121 137 153 169 x 39 29 18 17
10 10 26 42 58 74 90 106 122 138 154 170 x 40 30 20 19
11 11 27 43 59 75 91 107 123 139 155 171 x 24 18 12 11
12 12 28 44 60 76 92 108 124 140 156 172 x 23 17 10 9
13 13 29 45 61 77 93 109 125 141 157 173 28 22 16 8 7
14 14 30 46 62 78 94 110 126 142 158 174 27 21 15 6 5
15 15 31 47 63 79 95 111 127 143 159 175 26 20 14 4 3
16 16 32 48 64 80 96 112 128 144 160 176 25 19 13 2 1
80 01 0 0 02 00 - 40 0 T R X 600 - 1 00 0 TR X 400 - 2006 00
Figure 5: 1000 TRX LIU Shelf connections assignment
1.2 Shelf Manager(SMM)
1.2.1 Introduction
The communication between the system manager and the shelf manager is based on:
- Remote HPI
- Simple Network Management Protocol (SNMP)
- Remote Management Control Protocol (RMCP)
Two shelf management modules (SMM) are implemented: one active, and one backup forredundancy reasons. The SMM functions are defined as following:
- Board power-up
- Configuration of the various electronically keyed interfaces within the ATCA shelf: Baseinterface, Fabric interface, Update interface, Synchronization clock.
- Monitors, controls, and assures proper operation of AdvancedTCA boards and other Shelfcomponents,
-Watches over the basic health of the system, reports anomalies, and takes corrective actionwhen needed,
- Retrieves inventory information and sensor readings as well as receive event reports andfailure notifications from boards and other intelligent FRUs,
- Perform basic recovery operations such as power cycle or reset of managed entities,
- Provides low-level hardware management services to manage the power, cooling, andinterconnect resources of a shelf.
- Communicates with the System Manager.
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1.2.2 Connection
The following table give a list of all the shelf management command.
To log in SMM, use the following user name and password:
IP address See IP table description in IP address chapter (take 172.17.3.8 asexample)
User rootPass root
Connect method1 If SSW is already configured, telnet 172.17.3.8 via ATCA network(fromterminal PC)
Connect method2 out of band interface: Direct connect a network cable from terminal PC toSMM Ethernet port: 192.168.x.8(x is the ATCA shelf number)
Table 2: SMM connection method
1.2.3 Face plane & LED status
LED Color Description
Failure(OOS)LED1
Red The shelf manager board is outof service
Off The shelf manager board isworking properly
Power(OK)LED2
Green The shelf manager board isoperating properly
Off Otherwise
Active(Act) LED3
Amber The shelf manager board isactive
Off The shelf manager board is inthe standby mode
Blue (H/S) Blue The shelf manager board isready to be extracted
Off The shelf manager board is notready to be extracted. Do notremove the board during thisstate.
Ethernet 2 Green Link to backplane Ethernet 1 isavailable
Off Otherwise
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Ethernet 1 Green Link to backplane Ethernet 2 isavailable
Off Otherwise
Ethernet 3 Green Link to Ethernet is available
Off Otherwise
Ethernet 4 Yellow Active
1.3 Switch Board(SSW)
1.3.1 Introduction
The blade basically provides the following features:
- Managed 24 port Layer 3 Gigabit switch for base interface
- Gigabit Ethernet support for 14 payload slots
- 8 base and 1 fabric Gigabit Ethernet uplinks (SFPs) via rear transition module
- 15 port unmanaged Layer 2 Gigabit Ethernet switch for fabric interface
- ATCA Management Controller (IPMI version 1.5)
- SNMP agent for switch management
- Option for TDM clock generation and synchronization via CGM module
- Designed for NEBS level 3 and ETSI requirements
1.3.2 Connection
Connect method1 We can connect to Switch via COM port(need special cable), runVxworks command.
Connect method2 http://172.17.X.10, user:admin, pass:password
Table 3: SSW connection method
1.3.3 LED
Status and EthernetLEDs
Base interfaceLEDs
connector Reset key
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Status and Ethernet LEDs:
Name Color Description
OOS Red Out of service
Red: The blade is outofserviceOff: The blade is working properly
OK Green Power OK
Green: The blade is operating properly
Off: Otherwise
ACT Amber Active
Amber: The blade is active
Off: The blade is in the standby mode
H/S Blue Blue: The blade is ready to be extracted
Off: The blade is not ready to be extracted. Donot remove the board during this state.
ETH1 Orange On: Activity
Off: No activityGreen On: Link up
Off: Link down
ETH2 S Green 10 BaseT
Orange 100 Base Tx
ETH2 L Green On: Link up
Off: Link down
ETH2 A Orange On: Activity
Off: No activity
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During powerup
ST A Red Power good 3
Green FPGA initialized
ST B Red Power good 2
Green Power good of all DC/DCs
ST C Red Power good 1
Green Power up command from IPMC
OrangePower good 1 and power up command fromIPMC are indicated
During operation
ST AIndicates general activity via UART betweenboth boards.
Green No activity
Orange Activity
ST BIndicates the status at the Ethernet heartbeatconnection.
Red Heartbeat connection is dead
Green Active
Orange Warning
ST CIndicates the status at the UART heartbeatconnection.
Red Heartbeat connection is dead
Green Active
Orange Warning
ST LED status during startup:
During SW startup
ST A ST B ST C description
Red Red Red Software start
Orange Red Red Hardware initialization
Orange Orange Red Hardware initializationOrange Orange Orange Hardware initialization
Green Orange Orange Hardware initialization
Green Green Orange Hardware initialization
Green Green Green Hardware initialization done
Red Orange GreenSoftware initialization (from nowon, I/O via console is possible)
During SW shutdown/reset
Red Red Red Boot loader only!
Orange Red Orange Hardware shutdown
Red Orange Red Hardware shutdown
Base Interface LEDs meaning
Color Description
Green Port performed linkup but no activity
Orange Port performed linkup and there is activity
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1.4 OMCP/CCP
1.4.1 Introduction
The PENT/ATCA-715 is an AdvancedTCA compliant single blade computer offering high
processing performance. Four on-board PMC sites, redundant GBit Ethernet connection to theAdvancedTCA Base interface and standard I/O interfaces make it ideal for telecommunicationand datacom applications.
Important features are:
-Pentium M processor with up to 1.8 GHz speed
-Up to four GByte main memory DDR2 SDRAM with ECC protection
-Designed for PICMG 3.0 and 3.1 compliant systems
-Redundant AdvancedTCA Base interfacea
-Four on-board 64-bit/100MHz PCI-X compliant PMC slots
-Two USB 2.0 interfaces at face plate
-Optional on-board CompactFlash and 2.5 inch hard diska
-Support for Windows 2000/2003 and Carrier Grade Linux Ed. 3.1
-Intelligent Platform Management Controller (IPMC) compliant to IPMI V.1.5 with
redundant IPMB support
-Support for four PMC Modules with Telecom clocking synchronization
-Different accessory kits, for example:
>Rear Transition Modules (RTMs)
>CMC debug module
>Hard disk accessory kit>Cable accessory kits
1.4.2 Connection method
Connect method1 Login SMM, then
- telnet localhost 4503 to connect to OMCP1
- telnet localhost 4504 to connect to OMCP2
- telnet localhost 4505 to connect to CCP1
450X x=logical number
Connect method2 From BSC terminal PC, if BSC terminal is connected to SSW1:
- telnet 172.17.3.30 to connect to OMCP1- telnet 172.17.3.40 to connect to OMCP2
if BSC terminal is connected to SSW2:
- telnet 172.18.3.30 to connect to OMCP1
- telnet 172.18.3.40 to connect to OMCP2
/common/bsc/SCPRDISK SCPR disk MXBSC
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/common/bsc/RI RI files generated by CM MXBSC
/common/bsc/backup used for fast restore MXBSC
/common/bsc/OCPRDISK OCPR disk MXBSC
/var/log/MX/trace/daily daily trace MXBSC
/var/log/MX/trace/realtime realtime trace MXBSC
/var/log/MX/trace non-VOS trace MXBSC+MXPF
1.5 PC card
1.5.1 Introduction
The PC card(A100) is a general purpose device to provide for all of the functions that may not beincluded by the other Field Replaceable Units (FRUs).
The PC Card alarm board:
- Contains the Shelf FRU Information Store
- Contains rotary switches for setting SGAs
- Provides HA, SGA and configuration bit inputs
-Provides interfaces for up to two filter switches and four temperature sensors, for example, airinlet
- Provides Telco alarming, that is, relay outputs for major, minor, and critical errors and up to fouropto-solated inputs
- Visualizes the states and alarms via LEDs on the front panel
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1.5.2 LEDs and connecter
Failure(OOS)LED
Red On: The ATCAA100 alarm boardis outofservice
Red blinking: The shelf FRUinformation is invalid and no boardis powered
Off: The ATCAA100 alarm boardis working properly
OKLED
Green On: The IPMC has initializedproperly and is ready
Off: Otherwise
Blue(H/S)
Blue On steady: The ATCAA100alarm board is ready to beextracted
1.6 TP
B10 MXBSC supports TP v1/v2/v3 boards.
1.6.1 TPv1 Introduction
All TPGSM v1 board functions were grouped in the following modules:
Configuration Management
Fault Manager Application Alarms Management and Notifications
Performance Parameters Management
TDM Management TDM switching, E1 Alarms, TDM Clock Management
HDLC-LAPD Handler Management
SS7 Configuration Management
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ML-PPP Management
Qmux Handler Management
R/W Bits Handling Module
General Utilities Common Buffer Pool, Timers Management, Trace Routines, etc. - nottreated by this document.
We want to distinguish between several domains for TPGSM v1 operation by BSC application.
1) OBC application : Everything related to the telecom services of the TPGSM: Switching,SS7, HDLC, A-Trunks, E1. And management functions : Configuration manager, Faultmanager, Performance manager.(running with Pentium M).
The TPGSM Services domain is tightly integrated with the BSC application. Themessages are exchanged using the CMW communication system.It covers:
Configuration
Fault management
Performance Management
Telecom services
2) nE1oE module: part which is in charge of routing the user traffic between the TPGSMboard and the MUX board. The nE1oE module is managed using the nE1oE agentdelivered with the MX_PF software and located on the OMCP.
NE1oE stands for NE1 Over Ethernet: its role is to ensure the transport of data carried byE1 links over a Giga Ethernet network between MUX (LIUs) and TP/GPs.The NE1oE service covers:
Configuration
Role Assignment
Takeover
Reset
Fault Management
Start - Stop
Software Change
Hardware Management
PM Reporting
Traces/Logs Service
3) MX_PF : Everything related to the software running on the board, independently of what
that software does. This is mostly for supervision and control. No PM should benecessary for that domain. And at that level, the configuration is not controlled by BSCapplication.
The MxPF Services domain covers.
Task management (mostly process management).
SW management (ex: SW inventory services)
HW management (board status, hardware notification, remote inventory, INIT,Reset).
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TPGSM fault notification, subscribe/publish services.
These services are common to every board. This means that those services areaccessed by the same API for TPGSM/OMCP/CCP boards.
4) HardWare : Everything related to the HW aspects of the board, as seen through theATCA shelf manager. Likewise, this should concern only supervision and control.
The HW management domain (Interface1) is managed through Endur-X/IPMI. Thismeans that those services are accessed by the same API as for OMCP/CCP/SSWboards.The interface 1 covers:
basic board operations (Power On, Reset, Power Off),
HW events (HW failures).Indeed it means that the OBC part of the TPGSM board is treated like any other elementof the ATCA shelf for these generic services.
1.6.2 TP v2/v3 Introduction
With the introduction of High-speed Signalling Link(HSL) and IP transport in B10, a newgeneration of TPGSM board is necessary which is called TPGSM v2/v3.
TPGSM v2/v3 is an extension of the existing TPGSM with a new daughter board and all existingfunctions are kept. This daughter board is called TPIP, its main function is to handle the IPstacks, it has IP over E1 termination for up to 252 E1 links. TPGSMv2/v3 is compatible withMxBSC B9. It can be inserted in an MxBSC B9 platform without the need to change BSC SW.TPGSMv2/v3 will support the IP routing function and forwarding function, and also support the(ML)PPP connection management.
In addition to the services supported by TPGSM v1, TPGSM v 2 also supports the following
handlers as a part of TP_MAIN process:
E1 switch handler: It is in charge of the communication between the E1 switch driverand the TPGSM application. Especially, it is in charge of the configuration of the E1switch and of the fault that may occur on the E1 switch
IP routing handler: It is in charge of the communication between the IP forwarding functionand the TPGSM application. It manages the routing table configuration, the PM counters, thefaults, and the DHCP extractions.
Abis/Ater MLPPP hander: It manages the establishment, release and supervision of the(ML)PPP connection
1.6.3 Connection method
Connect method1
Use one serial cable which connect the PC COM port to monitor TPstartup
Baud rate 38400
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For connection to NE1OE part of TP ,refer to chapter 4.2.19
Connect method2 From BSC terminal PC, if BSC terminal is connected to SSW1:
- telnet 172.17.3.130 to connect to TP1
- telnet 172.17.3.110 to connect to TP2
if BSC terminal is connected to SSW2:
- telnet 172.18.3.130 to connect to TP1
- telnet 172.18.3.110 to connect to TP2
1.7 MUX board/LIU board/PEM board
1.7.1 Introduction
As defined in the MX Hardware Architecture and Principles, the LIU Shelf will have the followingexternal interfaces:
Up to 256 Physical E1 links termination
Two 1000 Base T Ethernet links
2 Redundant DC power supply
Debug interfaces.
The LIU Shelf will be structured with following internal entities:
One mechanical shelf including an interconnection backplane
Up to 16 LIU boards gathering 1 to 16 physical links each
Two MUX boards interfacing the TP GSM through the Gigabit Ethernet switches
Two Power Entry Modules (PEM)
Cooling Fans if needed.
1.7.2 Function of each board
The LIU board shall ensure the following functions:
Connection of up to 16 physical E1 interfaces (Tx / Rx)
Multiplexing and de-multiplexing of 16 E1 to/from the two MUX boards
LIU synchronization
Communication with the MUX boards for LIU board configuration and supervision
Detection of LOS on any E1 connected and in use
Storage of Remote Inventory data
Power up from each PEM (POL implemented on LIU board)
Hot insertion.
The MUX board shall ensure the following functions:
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Multiplexing and de-multiplexing of up to 16 E1 streams (16 E1 each) from theLIU boards
Control Plane and User Plane management to/from the GbE link
Configuration management and supervision of the LIU boards
1 GbE interface
NE1oE packing/unpacking to/from up to 32 physical entities (TPGSM boards, GPboards)
Communication with the other MUX Board (Master/Slave indication)
Debug interface
Storage of Remote Inventory datas (Refer to Appendix 1)
Power up from each PEM.
Hot insertion.
The Power Entry Modules shall ensure the following functions:
Power supply connection
DC power filtering
-48 V to 12 V DC/DC conversion
LIU Shelf
LIU boardTransf
LIU
LIU
Transf
Transf
Transf
PLD
TransfLIU
LIU
Transf
Transf
Transf
PLD
MX Platform
GbE
GbE
SSWW
SSWP
ATCA Shelf
MUX Board
NE1oE
MUX Board
NE1oE
PEM PEMLIU board
1.7.3 Introduction
In MXBSC, some trace are enable automatic, some other trace need manually to open them. Thetable show all the trace available for MXBSC
Board Trace type Enable Comments
OMCP/CCP/TP core dump file Automatic - VOS core, nonVOS core and selfRelient corefiles=/var/log/MX/dump/
-
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-
OMCP/CCP/TP Linux system log, Automatic - dmesg command to see the startup result- all the log file located in /var/log/
OMCP/CCP/TP SelfRelient log Automatic - selfRelient log file are stored in/var/log/MX/trace/srk/
OMCP/CCP NTP log Automatic - /var/log/MX/logs/NTP
OMCP/CCP VCE realtimetrace(SCPR,OCPR,TCU,DTC,TSC)
Request fromtraceterminal
-trace file will be finally stored in OMCP disk/var/log/MX/trace/realtime/
OMCP/CCP VCE daily trace Request fromtraceterminal
- trace file will be finally be stored in OMCPdisk: /var/log/MX/trace/daily/
OMCP MxPF current log Automatic - trace file will be finally be stored in OMCP disk:/var/log/MX/logs/
OMCP/CCP VCE Interactivetrace
Request fromtraceterminal
- trace file will be finally be send to trace facilityterminal,use du
TP/OMCP/CCP Non-VCEtrace(CMW/CMWP,
EIM,CPI,SWMGT,TP_MAIN,server_PH, SLH )
Manuallyactive from
each board
- trace file will be finally be stored in OMCPdisk: /var/log/MX/trace/
1.7.4 VLAN config
Without VLAN, all the communication will be broadcast to all the board, it will generate additionalload for each board to receive the message it dos not interested. In MXBSC, tagged VLAN isused to separate IP internal/external traffic and pure Ethernet telecom traffic.
Fixed values are used for the VLAN-Ids:
o No tag for VLAN1 (internal and external IP traffic). This is the default tag used fornon-tagged frames.
o Tag22 for VLAN22 (External O&M traffic through the SSW1)
o Tag23 for VLAN23 (External O&M traffic through the SSW2)
o Tag3 for VLAN3 (telecom traffic coming from Mux1)
o Tag4 for VLAN4 (telecom traffic coming from Mux2).
In the switch, only the assignment of VLAN ID to physical ports is needed. That meansfor each physical port describe the list of managed VLAN Ids (contains one ID for port
based VLAN, several for tagged VLAN).
The purpose of Tag3 and Tag4 is to send only telecom and supervision (based on broadcast)traffic on right switch ports to not impact other switch ports that are not concerned by thisEthernet traffic.
The purpose of Tag22 and Tag23 is:
To separate the external O&M traffic from internal traffic
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Isolate BSC and MFS internal subnet in case of rack-shared configuration and just letthe O&M traffic to be shared between BSC and MFS