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Quality of Service in a GSM-R PPPJean CELLMER
UIC ERTMS 2014
The RFF GSM-R project
Preliminary study started in 2000
Start of rollout in 2003 with the first supply contract given to Nortel
GSM-R scenario: Replacement of analog system : 14,000 km on a total of 32,000 km Unique train radio for new lines : East European High Speed Line first 10 year rollout Radio optimized for 8 Watt cab radios Planned number of users: 10,000 cab radios + 30,000 handhelds ETCS level 2 on high speed lines
Architecture: 1 Core Network active (+ 1 back up site) 17 Base Station Controllers, 2,500 Base Stations (radio sites)
The RFF GSM-R network architecture
2 MSCs (1 +1)17 BSCs2500 BTSsand: - A test platform including a test line- A national supervision centre
Port BouPort Bou
Tours
Reims
LyonLimoges
Rennes
Nantes
Guingamp
St Brieuc
Quimper
Vannes Redon
Le Croisic
Le Mans
Laval
Angers
Saumur
Sablé
Poitiers
Angoulème
Libourne
Bordeaux
Brive
Cahors
Morcenx
Dax
PuyooHendaye
Bayonne
Tarbes
Agen
Toulouse
Montauban
Perpignan
Carcassonne NarbonneMontréjeau
Arvan
Chateauroux
Nexon
Vierzon
St Florent
Bourges
Saincaize
Auray
La Ferté B
Chatellerault
Ruffec
Nevers
Gourdon
Moulins
St Germain des F.
Riom
Roanne
St Etienne
Montpellier
Nîmes
Toulon
Cannes
Vintimille
Aix
Orange
Valence
Romans
BéziersSète
ModaneGrenoble
Aix
Annecy
St Amour
Bourg
Ambérieu
Genève
Culoz
AlbertvilleBourg St MauriceGivors
Chasse
Chagny
Les Laumes
Dôle
FranoisBesançon
Mouchard
Arc et Senan
Gannat
Mulhouse
Bâle
ColmarChaumont
Culmont Ch.
EpernayChalons
Vitry le F. Toul NancyReding
Forbach
Apach
Metz
Charleville M.
Hirson
Longwy
Bening
Vittel
Merrey
Kehl
Jeumont
Tergnier
Longueville
Coulommiers
Tournan
Laroche M.
Dreux
Le Havre
Rouen
Plaisir G.
Clères
Rue
Abbeville
Boulogne
Calais
Valenciennes
Tourcoing
Dunkerque
Baisieux
Amiens
Beauvais
Persan
Mantes
Hazebrouck
Arras
Lens
Bethune
Cambrai
Lille
Longueil
Blois
Orléans
Etampes
Brest
Busigny
Tarascon
Avignon
Clermont -F.
Molsheim
Thionville
Neuenbourg
ToursDijon
Reims
Marseille
Lyon
Rennes
Nantes
Guingamp
St Brieuc
Quimper
Vannes Redon
Le Croisic
Connerré
Angers
Sablé
Angoulème
Libourne
Brive
CahorsArcachon
Morcenx
Dax
PuyooHendaye
Bayonne
Tarbes
Toulouse
Perpignan
Carcassonne NarbonneMontréjeau
Arvan
Chateauroux
Nexon
Vierzon
St Florent Saincaize
Auray
Courtalain
Chatellerault
Ruffec
Moulins
St Germain des F.
Riom
Roanne
St Etienne
Montpellier
Nîmes
Toulon
Cannes
Vintimille
Aix
Arles
Orange
Valence
Romans
BéziersSète
St André le G.
Aix
Annecy
St Amour
Ambérieu
Genève
Culoz
AlbertvilleBourg St MauriceGivors
ChasseChambery
Mâcon
Chagny
Les Laumes
Clerval
Gannat
Belfort
Mulhouse
Bâle
ColmarChaumont
Culmont Ch.
Epernay
Vitry le F.
Lérouville
Bar le Duc
Reding
Forbach
Apach
MetzConflans J
Charleville M.
Longuyon
St Dizier
Pagny Rémilly
Vittel
Merrey
Jeumont
Tergnier
Provins
LonguevilleChartres
Le Havre
Plaisir G.
Clères
Rue
Abbeville
Boulogne
Calais
Valenciennes
Tourcoing
Dunkerque
Baisieux
Amiens
Beauvais
Hazebrouck
Arras
Lille
Blois
Orléans
Etampes
Brest
Ormoy
Strasbourg
Busigny
Miramas
Tarascon
-F.
Molsheim
Neuenbourg
ChateauThierry
Creil
Paris
Troyes
Blesmes
Aulnoye
Liart
Douai
Thouars
Laon
Why a PPP?
June 2004: a new French Law authorising PPP (Public Private Partnership)
Why a GSM-R PPP? Rollout time schedule could be reduced RFF and SNCF could benefit from additional competencies in term of rollout
and network operation thanks to mobile operators involvement RFF financial risks would be limited since the price is definitely fixed in the
Partnership contract Operation costs could be reduced thanks to mutualisation of activities and
resources (a common network operating centre) Additional revenues allocated to the private partner, reducing the price paid
by RFF RFF CAPEX postponed and partly changed in OPEX.
The main aspects of the French PPP contract
A 15 year contract signed in March, 2010 with a new company named SYNERAIL
Complete rollout of the GSM-R network
Operation of the complete GSM-R network, including the part which was built by RFF (transfered to SYNERAIL in March, 2011)
Maintenance, upgrade, replacement of all necessary hardware and software equipment until 2025
New services on the network in order to improve business revenue
Future High Speed Lines: connection to the GSM-R national network and support of local GSM-R Base Station Subsystem (the radio sites)
A very high grade of service: Train to ground radio, 100% compliant to EIRENE specification ETCS level 2 data transmission on High Speed Lines
What’s not in the PPP
Transmission links between network elements are still supplied by RFF.
These fiber optic or copper cables already exist and are used for various telecommunication applications. They could not be dedicated to GSM-R and transfered to the GSM-R PPP.
This share of responsibilities create some difficulties and needs a good organisation.
Fixed telephony is also supplied by RFF. The Private Partner is just responsible for integration of these equipment in the end to end system.
GSM-R PPP: Area of responsibility of SYNERAIL
7
BSS
Base Station Subsystem
BSC
BTS
BTS
NSS
Network Switching Subsystem
BSC
(7 sites)
FTS: SNCF (Primary and secundary controllers)
Cab radios
Handhelds
Lineside Telephone
Sets
(Base Transceiver Station)
(Base Station Controller)
SDH Transmission: SNCF
SYNERAIL domain
Local loop: copper cables and fiber optics: SNCF
A complex contractual organisation
8
RFF
Temporary building consortium : SYNERAIL CONSTRUCTION
SYNERAILStakeholders Banks
Consortium for operation and maintenance : SYNERAIL EXPLOITATION MAINTENANCE
Sub contractor N
Sub contractor
N+1
Small companies
Small companies
Sub contractor N
Rollout independant
Controler
Stakeholders contract
PPP contract
Financing contract
Building contract Operation and maintenance contract
Sub contract Sub contract Sub contract Sub contract
Interface contract
Certification of sites
Specific contractual relationship
Sub contract
Lessons learnt from RFF experience
A very complex organisation
Managing a PPP contract is all but simple: Financial, operational, technical aspects have to be dealt with by numerous contractors.
Too many interfaces
RFF is the customer but RFF is also the supplier of transmission links, works along the track safety etc.
Lessons learnt from RFF experience
The temptation to over specify
In a PPP contract the private partner is responsible for the network design and RFF should have only issued functional specifications, mainly expressing RFF’s needs in term of services, QoS, maps of lines to be covered, railway constraints.
But RFF explained very precisely its internal rules: no candidate took the risk of not following RFF’s rules and no one showed creativity. SYNERAIL designs and builds the same network as RFF did.
Quality of Service in a GSM-R PPP network
There is a contractual relationship between RFF and the private partner. SYNERAIL is committed to:
Guarantee a permanent GSM-R service (train radio and support for ETCS level 2)
Instantly inform RFF in case of any loss of service Keep the network as new until the contract end (2025) Pay penalties for every break in the contractual rules
RFF is permanently informed of the network status
SYNERAIL Exploitation comes from a mobile operator (SFR): Technicians are very professional, well skilled and trained There is an efficient human resource sharing with SFR But sometimes, there is a need to better understand the railway specific
environment and constraints
/ UIC/PTA 23 May 20111111
The network Operation Centre is shared with a mobile operator’s
/ UIC/PTA 23 May 20111212
SFR operation centre: one table is dedicated to GSM-R
QoS: Level of performance
SYNERAIL is committed to deliver the GSM-R service with a contractual level of performance:
Radio coverage: minima signal level > - 98 dBm pour train radio and > -92 dBm for ETCS level 2
Handover on Power Budget: > 90%
Handover ping pong: < 1%
Voice quality: MOS > 3 and RXQUAL < 2 (*)
Call drop rate for voice < 1.5%
Call drop rate for ETCS < 1 call drop per 100 hours
Etc.(*) RXQUAL is a GSM-R parameter which qualifies the received signal quality
/ UIC/PTA 23 May 20111313
Quality of Service: Service availability
Three categories of sites Normal sites: Conventional lines Critical sites: High Speed Lines + around 100 sites on conventional lines ETCS level 2 sites
For every radio site a maximum downtime per year is specified: 99.51% availability of service for conventional (40 hours cumulative max outage) 99.91% availability of service for critical (8 hours cumulative max outage) 99.99% availability of service for ETCS level 2 (52 mns cumulative max outage)
In addition Time To Repair (TTR) per site is limited to 4 hours Every service affecting breakdown must not last more than 4 hours
QoS: Information of RFF and SNCF
In case of a service breakdown:
SYNERAIL must inform SNCF railway operator in less than 5 minutes of any issue which could have a negative effect on railway traffic
They must confirm in less than 20 minutes that the issue is not fixed and explain the consequences in term of affected area, likely duration of the problem, possible reason for this issue to go on etc.
After service recovery:
SYNERAIL must inform SNCF in less than 5 minutes
In case of a Railway Emergency Call:
SYNERAIL must provide, on request of SNCF, a provisional technical information in less than 15 minutes (call trace) and complete information in 24 hours,
/ UIC/PTA 23 May 20111515
Some railway specific issues
In spite of their professional experience, SYNERAIL technicians are facing some new issues:
• No alarm out-of-service sites:• A Public GSM site is monitored by counters of traffic• A GSM-R site (non ETCS) is not used to support permanent traffic• In case of loss of service without alarm notification (i.e. antenna) train
drivers are the only source of information: no way to fix the issue in less than 4 hours!
• Very high requested availability:• A public network can live with several sites out-of-service for hours/days
especially far from peak hours• A GSM-R network needs to be permanently in service, all sites (no
coverage overlap), especially ETCS sites
• A strong need to inform railway operators in case of a breakdown and after service recovery:• Some outages could lead to a railway traffic stop.
/ UIC/PTA 23 May 20111616
Conclusion
Operating a GSM-R network in a PPP mode is a good way to improve the Quality of Service thanks to the presence of mobile operators skilled and well trained people.
But these professionals often need a time to fully understand railway constraints and specificity.
Questions?
/ UIC/PTA 23 May 20111717