Evolution of mobile telephony and data at CERN

Rodrigo Sierra

Communication Systems group, IT Department, CERN

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Agenda• CERN mobile services• Mobile services evolution• Mobile network migration

• Department challenges• Advanced services• Migration process & planning

• Mobile data evolution• Conclusions

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CERN mobile services• Mobile services:

• Single contract with a Swiss operator• Closed VPN comprising > 5800 mobiles• Voice and data services (including UMTS/3G and LTE/4G)• Mobile calls from Switzerland routed via the CERN telephone exchange• Dedicated access to CERN’s Intranet

• To allow secured and controlled access to CERN intranet servers

• Roaming worldwide

• Infrastructure• > 50 km of leaky feeder cable covering underground facilities• CERN’s own infrastructure to cover LHC tunnel• 68 radio/transmission sites at CERN

• Technologies• GSM, UMTS (3G) and LTE (4G)

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Evolution - Déjà vu!• UPS for mobile sites - 2010• SIM cards replacement - 2010• 3G in LHC (UMTS900) – 2012• 3G in the injector chain – 2013• Mobile network SWAP – 2013• Sunrise network evolution - 2014• LTE pilot in LHCb (L800) - 2014

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• 3G & LTE in all underground facilities• 3G & LTE on surface in… France• > 100Mbps DL in the caverns

• Having very interesting tariffs?

Evolution - Déjà vu?

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Mobile network migration• What?

• Swisscom will replace Sunrise the 1st of July 2015

• Why?• Swisscom has won the call for tender for mobile services

• When?• Installation started in January• All services should be ready in June• The operator will be swapped the 1st of July

• How?• Swisscom’s network is being installed while Sunrise’s one is

still in operation• Sunrise will be decommission once Swisscom is operational

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Mobile network migration• Mobile services will be improved:

• LTE (4G) in the Swiss part• UMTS (3G) and LTE (4G) in the French part (authorization

pending from French regulator)• UMTS (3G) and LTE (4G) in the underground facilities• LTE-Advanced in the LHC experiments: 150Mbps DL• Reminder: No Wi-Fi in the tunnels after LS1

• New tariffs:• Very interesting tariffs negotiated (~ 50% reduction in

average)

• New operator:• New SIM card and new number

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Mobile network migrationNetwork deployment• The network must be installed while operating the current one:

• New space, fibers & power supplies required in all sites• New mast/antennae for outdoor coverage

• Network complexity:• 2G, 3G and 4G in all sites• 14 outdoor sites• 37 indoor sites: LHC & injector chain covered• 17 CERN indoor sites in the LHC (REs & TI8)

• Advanced services must be integrated:• CERN APN, roaming control, PBX interconnection…

• French and Swiss regulation:• Radio emission• Construction permits

• The new network must be ready in 6 months

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Architecture

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Architecture• Underground facilities

• > 50 km of leaky feeder cable • 2G, 3G, 4G, TETRA & TETRAPOL• Signal overlap for redundancy and capacity• Frequency and technology planning

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Departments collaboration• Contract – FP• Legal permits & authorizations - DG• Integration of racks and cabling – EN & GS• Power supplies for all sites - EN• 100s of fibers to be pulled - EN• Civil work to build outdoor sites - GS• Temporary storage & transport- GS• SIM card distribution – Secretaries• CERN administrative tools & billing - GS

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IT department challenges• Deployment in 6 months• Coordination• Regulators and legal entities• New numbering plan• Fixed-line network moved to Swisscom• Infrastructure compatibility with LTE• Advanced services• SIM card migration• ‘Seamless’ operator migration

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Advanced services• CERN intranet connection• CERN voice VPN• CERN PBX interconnection• Email2SMS gateways• Roaming cost control• Automatic billing• User provisioning

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ACL

Operator mobilenetwork

Operator backbone CERN GPN

Internet

Internet APN

APN

2 x 1Gbps

CERN intranet connection• CERN intranet connection (CERN APN):

• Fixed IP address related to the phone number (16abcd -> 10.14.1ab.1cd)

• Internet APN by default:• Swisscom IP address

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CERN voice VPN

Operator3

Operator2

Operator1CERN’s national mobile

operator network

CERN’s VPN

PRIAllowed CallForbidden Call

CERN’s fixed network

DISA feature

Non CERN phone user

LCS

VPN CERN

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SIM cards migration• ALL SIM cards must be changed (~6000)

• Sunrise SIM cards will stop working in July

• Distribution of Swisscom SIM cards in June via secretariats and Labo Telecom

• Special procedures:• Modems• Users not at CERN in June

• Planning, FAQ, procedures…• To be published in https://cern.ch/gsm-migration

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Seamless migration• Number change (16xxx won’t change)• All subscriptions activated simultaneously• Surface:

• Negotiating some days of overlap

• Underground facilities:• Only one operator available at the same time

• Sunrise subscription will stop the 1st of July:• Sunrise numbers redirected to a voicemail in July

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Mobile data evolution

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Mobile data evolution• Cake (throughput):

• Baking sheet (bandwidth)• Thickness (power – S/N)• Slices (time)• Ingredients (technologies)• Density (latency)

• Shannon’s:

Bandwidth

Power

Time

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Frequency Division Duplex• Downlink and Uplink separated in frequency• Uplink limited by terminal power (battery) & Noise

Downlink Uplink

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GSM (2G)• FDMA -> Low bandwidth (200KHz)• TDMA -> Channel divided in 8 slots

• Ingredients:• Old technology (early 90s)• Designed for voice• High latency

• 1 slice of a cookie difficult to digest• 9.6 kbps DL & UL• Latency: ~ seconds

GSM

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GPRS (2.5G)• FDMA -> Low bandwidth (200KHz)• TDMA -> Up to 4 slots DL and 2 UL

• Ingredients:• GSM technology• New coding scheme

• Several slices of a cookie difficult to digest• 80 Kbps DL & 40 Kbps UL• Latency: ~ 1s

GPRS

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EDGE (2.75G)• FDMA -> Low bandwidth (200KHz)• TDMA -> Up to 5 slots DL and 3 UL

• Ingredients:• GSM technology• 8PSK modulation• New coding scheme

• Several slices of a healthy cookie• 296Kbps DL & 177.6Kbps UL• Latency: ~ 150ms

EDGE

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UMTS (3G)• WCDMA:

• High bandwidth (5MHz)• Code division -> No more time slots

• Ingredients:• Code control• Power/noise control• Computational power

• One cake easy to digest• 384 Kbps DL & UL• Latency: ~ 150ms

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UMTS evolution (3.5G)• Powerful devices: Smartphones

• More ingredients Downlink:• Modulation (16QAM, 64QAM) -> x2, x3• Number of codes (10, 15) -> x2, x3• Multi-carrier -> x2, 4…• MIMO -> x2, 4…

• One healthy big cake• 21/42/84… Mbps DL & 5.6/12/23/70… Mbps UL• Latency: < 50 ms

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CERN ‘allergies’• Ingredients:

• Modulation (16QAM, 64QAM) • Number of codes (10, 15) • Multi-carrier

• Double, triple… operator infrastructure + terminals evolution

• MIMO • 2nd leaky feeder study + terminals evolution

• Antihistaminic:

• Current cake (HSPA+):• 21Mbps DL & 5.6 Mbps UL• Latency: < 50 ms

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LTE (3.9G)• OFDMA (DL) & SC-FDMA (UL)

• Higher spectrum efficiency

• Ingredients:

• Huge cake but careful with allergies

Downlink Uplink

SISO 10 MHz 44.7 Mbps QPSK 10 MHz 7.2 Mbps

SISO 20 MHz 89.7 Mbps QPSK 20 MHz 14.4 Mbps

2x2 MIMO 20 MHz 172 Mbps 16QAM 20 MHz 57.6 Mbps

4x4 MIMO 20 MHz 325 Mbps 64QAM 20 MHz 86.4 Mbps

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LTE Advanced (4G)• Smartphones evolution (real computers)• Ingredients:

• Carrier aggregation (Up to 100 MHz)• MIMO (8x8 DL, 4x4 UL)• Small cells (128QAM…)• Coordinate transmissions (several cells into one)

• 3* Michelin cake: Bon appétit!

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Conclusions• Mobile migration:

• Challenging project with high visibility• Mobile services improved• CERN monthly bill reduced• SIM card and number changed

• Mobile data evolution:• HSPA+ and LTE in the tunnels (no Wi-Fi)• LTE Advanced in LHC experiments (>100Mbps)• LTE/Wi-Fi integration for a technical forum?

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Why I can’t keep my current number?

• We can transfer only active numbers (6,000 of the 10,000 range).• As soon as a number becomes inactive (i.e. someone leaves) the

number reverts to Sunrise• CERN should pay 10,000 subscriptions per month to keep all

numbers active for the duration of the contract with Swisscom so none will be reverted to Sunrise

• In Switzerland, the capacity for moving numbers between operators is 500/day (12 days to move our current active numbers)

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Transition period• What happens in case of delay ?

• Sunrise contract ends on the 31st of June.• One month of delay will cost ~100 KCHF

• Provided that Sunrise is willing to maintain the service

• Why such a short transition period ?• 7 months and half is long period to keep the “motivation” of the

current operator• During this period any changes are frozen• The new operator needs to start as soon as possible to start

generating revenues

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SitesOutdoor (14 sites):• Meyrin (3 sites):

• Building 60• Water tower• Building 361 (PS)

• Prevessin (2 sites):• Building 866• Building 887

• SPS (1 site):• BB4

• LHC (8 sites)• SD2, 4, 5, 6, 7, 8• SZ33• SDX1

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SitesIndoor (37 Swisscom sites + 17 CERN sites)• LHC:

• 9 sites on the surface covering the lifts and caverns• 16 CERN sites in the REs covering the tunnel• SCX5

• Transfer lines :• 1 sites covering TI2 and 1 CERN site covering TI8

• SPS (8 sites)• Meyrin:

• PS, AD, LINAC3, LINAC 4, N_TOF, CFT3, ISR, DIRAC, ISOLDE• Buildings 358, 2013, 839

• Prevessin:• North area, building 911

• SM18 (1 site)• Transmission:

• Buildings 58, 513, 874

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PlanningDate Work

Dec 14 – Feb 15 Site surveys and network design

Dec 14 – Mar 15 Regulators and construction permits

Feb 15 – Jun 15 Network deployment

15th June 2015 Fully operational services

June 2015 SIM cards distribution

1st July 2015 Operator swap