The optical NREN of S&M: New solutions in infrastructure and monitoring Zoran Jovanović, Slavko Gajin, Mara Bukvić, Pavle Vuletić, Djordje Vulović Belgrade University Computer Centre - Serbia & Montenegro

Telecommunications background 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  Intercity 155Mbps – €/month  Intercity 622Mbps – €/month

Alternative dark fiber network (1) End of Establishment of alternative dark fiber infrastructure – workgroup  Ministry of telecommunications,  Ministry of science, technology and development  NIS, Serbian oil and gas distribution company  EPS, Electric power industry of Serbia  ŽTP, Serbian rail  PTT Serbia  Serbian NREN (RCUB)

Alternative dark fiber network (2) Alternative dark fiber project failed Telekom Srbija more cooperative for the initiatives from the Government OPGW cable on Belgrade – Hungarian border and Belgrade – Croatian border lines Other companies (NIS, ŽTP) have small parts of fiber network installed NIS is installing fiber on all new pipelines In cities, fiber is being installed in heating and water pipeline channels

Year 2002 SinSEE Project: Donation from the German government - active networking equipment Fiber lines established  RCUB-Rektorat (5km)  RCUB-Novi Sad (95 km – 23dB attenuation)  RCUB-Vinca (15km) All lines installed and working

Year 2003 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 not yet provisioned  8 locations in Belgrade  3 locations in Novi Sad  2 locations in Kragujevac  4 locations in Niš

Year 2004 Annex of the contract with Telekom Srbija Phase 1:  Subotica – Szeged! (40 km) Phase 2:  Novi Sad – Zrenjanin  Beograd – Šabac (90 km)  Beograd – Valjevo (90km)  Valjevo – Užice (89 km)  Užice – Čačak (58 km)  Čačak – Kraljevo (33 km)  Kraljevo – Kruševac (83 km)  Kruševac – Niš (84 km)  3 locations in Belgrade

Year 2004 Annex of the contract with Telekom Srbija Phase 3:  Beograd - Pančevo (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)  2 locations in Belgrade

Locations in Belgrade

Total fiber length Price for domestic dark fiber lease is very close to the dark fiber price in deregulated telecommunications markets Total inter-city fibers: Approx km Total intra-city fibers: Approx. 150km

Dark fiber timeline All the lines from the first contract with Telekom Serbia were supposed to be finished by the end of 2003 Slow dark fiber service provisioning Problems with permissions for last mile installations especially if digging is necessary Phase 1: May 2004 Phase 2: September 2004 Phase 3: November 2004

Equipment and technologies Gigabit Ethernet  Low cost interfaces  Use of low cost L2 or L3 switches  More then 100km range  Sufficient at the moment in Serbian NREN  Use of CWDM

CWDM test – July/August 2003 Cisco CWDM test kit Replaced 1000BaseZX Belgrade – Novi Sad (95 km – 23dB att.) 4 Gbps Etherchannel BG Cisco 6509 NS Cisco nm, 1510 nm, 1550 nm, 1590 nm CWDM MUX-4 CWDM MUX-4

Total attenuation Telekom Srbija has G.652 fibers Total attenuation approx: 23dB+3dB+4dB = 30dB CWDM 1000BaseZX optical budget: 30dB Problems expected on 1470 nm 45 days without any carrier transition

CWDM experiment conclusions Can be used on intercity lines (100km) Reliable solution, Low cost solution Easy bandwidth upgrade Great flexibility for different logical topologies

CWDM Problems Problem with signal amplification:  EDFA cover narrow wavelength range (typically C- Band or L-Band)  More then one EDFA must be used in order to cover more than two wavelengths (1530nm and 1550nm)  EDFA - Expensive solution (Offer: € (price with a discount for academic institutions) for Belgrade – Subotica – 220km for 4 wavelengths (1510, 1530, 1550, 1570nm) – two preamplifiers and two boosters)  LOA – Cover broader wavelength range. At the moment of our analysis were available only as product evaluation kits. Offer: 2500$ per LOA and 2000$ per evaluation kit for 12dB amplifier

Our solution Majority of intercity links are shorter than 100km – daisy-chained If needed - OEO conversion using L3 switches 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

Potential Belgrade – Novi Sad – Subotica - Hungary connection

Southern part of the network All distances < 100km Easy logical channel separation for cross- border connections One 4-wavelength CWDM kit (OADM multiplexers and interfaces) - used for CWDM testing on all lines. Active equipment (switches) already purchased for all the cities

NetIS – Network Information and Monitoring System Information system  Logical network image in database  Hierarchical data organization with flexible users permissions  Auto-Discovery – interfaces, WAN/LAN topology, IP addresses  Easy to use Windows application for management (Windows Explorer like) – drag&drop, copy/paste...  Web based interface for user access

NetIS

NetIS – Network Information and Monitoring System Monitoring system  Monitors Traffic Ping Link status UDP/TCP port status Arbitrary SNMP variable (BGP/MPLS/FR status, memory/processor/disk usage etc.) plug-in for external monitors  Alarms Based on monitor response Notification – event log, , SMS, web access

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 is a technology which Serbian NREN will most probably use in the near future NetIS  main monitoring tool  free only for all NRENs

Thank you for your attention Questions