GSM-R Quality of Service for ETCS · • a high speed line • a high capacity line •a low...
Transcript of GSM-R Quality of Service for ETCS · • a high speed line • a high capacity line •a low...
John HarmerUnisigEuroRadio WG
GSM-R Quality of Service for ETCS
Chiel SpaansGSM-REuroRadio WG
The Railways perspective ...
• Safety
• Capacity
• Reliability
• Interoperability
Railway Requirements for ETCS
Train Operators are requiring a Railway
Infrastructure which delivers:
• a high speed line
• a high capacity line
• a low capacity line
• an urban railway
• and a freight-only line.
Railway Requirements for ETCS
Different requirements for:
• train awakening
• entering a Level 2 area
• extending a Movement Authority
• RBC handover
• crossing a border
ETCS Scenarios
Normal Scenarios:
• Train doesn’t wake up
• No network found
• Losing RBC connection
• Errors during transmission
• Etc.
ETCS Scenarios
Error Scenarios:
The Industry perspective ...
The standardisation process:
• Railways requirements
• Unisig specifications
• GSM-R Operators Group specifications
Structure
or...
EEIG
UNISIG
GSM-R
REQUIREMENTS
REALITY
Structure
Quality of Service, or "QoS"
• a way of stating a requirement
What is QoS?
• for general communications...
• Connection establishment delay
• Connection establishment failure probability
• Maximum/ Average/ Minimum Data Rate
• Transfer Delay
• Transfer Delay variation
• Error ratio
• Priority
• Security, leading to
a QoS Parameter Set
Communications QoSTypical parameters:
we all use this
- without realising...
• Starter
• Main Course
• Dessert
• Beer, wine, coffee
• Cost
• but parameter depends on:
• Time of day? Location? Previous meal?
• leads to...
a QoS Parameter Set.
Food & Drink QoSTypical parameters:
• Network registration delay
• Connection establishment delay
• Connection establishment error rate
• Transfer delay
• Transmission interference rate
• Connection loss rate
• Service availability
• Re-connection time?
• but what is the network...
ERTMS Parameters
the Data Path
FixedNetwork
Side(Infra
operator) Mobile Side(train operator)
GSM-RMOBILE
ETCSOn-board
RBC
VPN
GSM-R
BSCMSC
BTS
GSM-R(networkoperator)
Example 1: Delay
high speed
regional
4s 8s 12s
48.7%<4s
92.9%<7s 99.9964%
<12 s
0s
• realise call has dropped
• re-establish call
• setup safe connection
Example 2: Call drop
10s
15s
8s
33s
no GSM authentication or ciphering
7s
25sfast call setup
7s
24s
• Railway Requirements
• Unisig Class 1 Subset093
• FFFIS for Euroradio
• GSM-R Test Specification
• Eirene FRS
Documents
• Unisig Class 1 Subset093
and what next...
The Future ...
Operational Cases
• Border crossing
• QoS impact analysis for different
types of lines?
Next Steps
Test Tools
• Specification
• Standardisation
Next Steps
Validation
• GSM-R only
• End to End Communication