NREN on dark fibre with CWDM - experience of S

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NREN on dark fibre with CWDM - experience of SM
Zoran Jovanovic, Belgrade University Computer
Centre RCUB
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Deregulation

• Telekom Srbija monopoly until June 2005
• Telekom Srbija is (almost) the only owner of
  intercity fibers
• Telekom Srbija does not lease dark fiber
• Expensive high capacity digital links
• New owners are appearing Power company, Oil
  company, Railway,
• Cable TV operators in towns

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Year 2002

• SinSEE Project Donation of German ministry for
  science and technology in active networking
  equipment.
• Fiber lines established
• RCUB-Rectors office (5km)
• RCUB-Novi Sad (95 km 23dB attenuation)
• RCUB-Vinca (15km)
• All lines installed and working

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Awareness ceremony with PM

• Intercity dark fiber was given only for testing
• GBIC ZX were for Vinca institute used for
  intercity connection
• Video conferencing of the minister with other
  university centers
• Service at the operator didnt exist pricing?
• Strategic approach to include the new optical
  infrastructure that is appearing

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Year 2003 Signed

• Contract with Telekom Srbija Q3 of 2003
• Novi Sad Subotica (130 km)
• Beograd Kragujevac (130 km)
• Beograd Niš Gigabit Ethernet over SDH (250
  km)
• Lines are now being finally tested
• 8 locations in Belgrade
• 3 locations in Novi Sad
• 2 locations in Kragujevac
• 4 locations in Niš

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Key problems in implementation

• Getting building permissions for dark fiber
  layout to the university, high school or
  institute buildings
• Winter without digging
• Testing by the operator
• The only customer with this service
• Buildings of the operator should be avoided for
  telehousing by laying out a optical cable to the
  nearest school or institute example Belgrade -
  Kragujevac

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Year 2004 - signed

• Annex of the contract with Telekom Srbija
• Phase 1
• Subotica Szeged! (40 km) - SEEREN
• Phase 2
• Novi Sad Zrenjanin
• Beograd Šabac (90 km)
• Beograd Valjevo (90km)
• Valjevo Užice (89 km)
• Užice Cacak (58 km)
• Cacak Kraljevo (33 km)
• Kraljevo Kruševac (83 km)
• Kruševac Niš (84 km)
• 3 locations in Belgrade

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Year 2004 - Signed

• Annex of the contract with Telekom Srbija
• Phase 3
• Beograd - Pancevo (20 km)
• Kraljevo Novi Pazar (91 km)
• Niš Pirot (71 km)
• Niš Leskovac (46 km)
• Leskovac Vranje (68 km)
• Niš Bor (130 km)
• Novi Sad Sombor (72 km)
• 7 new locations in Belgrade

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Subotica
NREN of
NREN of
Sombor
Serbia
Serbia
and
and
Szeged
/
Hungarnet
SEEREN/GEANT
Zrenjanin
Montenegro
Montenegro
N
OVI SAD
Local
ISP
Pancevo
Telekom
Nodes

B
EOGRAD
Srbija
Šabac
National
N
OC
Core
Nodes
Valjevo
V. Plana
Bor
Athens
/
GrNet
Gbps
nodes
SEEREN/GEANT
Kragujevac
International
Kraljevo
Užice
Cacak
1Gbps/100Mbps
Kruševac
34
Mbps
N
I
Š
Pirot
Internal

Novi
Leskovac
2
1
Gbps
Eth
ernet
Pazar
Vranje
1
Gbps
Eth
ernet
Podgorica
1
Gbps
Eth
/SDH
2
Mbps
EuroPACS
2004
UChHIS
and Telemedicine
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Locations in Belgrade
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University hospitals on the NREN

• GE MAN that will connect most advanced hospitals
  in Belgrade
• In Serbia, all medical faculties will have a
  1Gbps connection
• More than 30 buildings of the campus of the
  Medical faculty and Dentistry faculty in Belgrade
  will have 1Gps connections by the end of 2004
  Medical campus laying cables along the heating
  pipes

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Equipment and technologies

• Gigabit Ethernet
• Low cost interfaces
• Use of low cost L2 or L3 switches
• Sufficient at the moment in Serbian NREN
• Use of CWDM
• Planning to use of optical amplifiers

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CWDM test July/August 2003

• Cisco CWDM test kit
• Replaced 1000BaseZX
• Belgrade Novi Sad (95 km 23dB att.)
• 4 Gbps Etherchannel

1470 nm, 1510 nm, 1550 nm, 1590 nm
CWDM MUX-4
CWDM MUX-4
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Total attenuation

• Telekom Srbija has G.652 fibers
• Total attenuation approx 23dB3dB4dB 30dB
• CWDM 1000BaseZX optical budget 30dB
• Problems expected on 1470 nm
• 45 days without any carrier transition

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CWDM experiment conclusions

• Can be used on intercity lines for up to 100km
• Reliable solution,
• Low cost solution
• Easy bandwidth upgrade
• Great flexibility for different logical topologies

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CWDM Problems

• Optical amplification
• EDFA cover narrow wavelength range (typically
  C-Band or L-Band). In CWDM will be used for a
  single lambda, when a lambda is dropped,
  amplified and added.
• LOA Cover broader wavelength range. At the
  moment of our analysis were available only as
  product evaluation kits. Noisy, low
  amplification, narrow bandwith.
• Experimental OA for the whole range - Japan

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Our solution

• Majority intercity links are shorter then 100km
  daisy-chained
• If needed - OEO conversion using L3 switches
• Replacing the OEO conversion with EDFA OA to
  reduce RTT
• Drawbacks in totally Ethernet network
  relatively slow convergence, added delay
• Idea Justify the use of dark fiber through fast
  and cheap connection provisioning. Later find the
  best solution for the network

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Potential Belgrade Novi Sad Subotica -
Hungary connection
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Strategy

• Using CWDM until there is a request for higher
  bandwidth
• Try to establish our own intercity optical
  infrastructure North South backbone with G.655
  cables combining with e-government
• Use fiber of other dark fiber suppliers fault
  tolerance
• Establish DWDM if we dont get our own fiber
• Establish a SEE backbone for NRENs

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Conclusion

• Widespread use of inter- and intra-city dark
  fiber is the main direction in which Serbian NREN
  is moving
• Cross-border dark fiber connections in SEE region
  are the next step for inter-NREN connections
• CWDM with 1 GE is a reliable technology which the
  Serbian NREN will most probably use in the near
  future

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Thank you for your attention

• Questions