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2.

Layer 1 ­ regional links between NOCs and local Points of Operation and Presence

(POP).

3.

Layer 2 ­ communication infrastructure at the metropolitan level and the communication

infrastructure of the connected institution. This layer is operated by each connected

institution and, usually, includes the connection to RoEduNet's NOC or POP. However,

RoEduNet operates three metropolitan area networks in Bucharest, Iasi and Cluj Napoca.

The topology of the network, layer 0 and layer 1 is presented in Figure 58 where NOCs are

represented

using

rectangles and POPs are

represented using ovals.

The backbone consists of

three gigabit rings for the

eastern part, the western

part and the center of the

country. The eastern ring

connects the Galati and

Iasi NOCs to the main

NOC in Bucharest. Also,

to the eastern ring the

NREN from Republic of

Moldova  (RENAM)  is

connected.

This

connection is operated by

RoEduNet NOC in Iasi,

the  STM1  line  from

Figure 58: RoEduNet topology ­ January 2008

Chisinau  to  Iasi  was

installed and it is operated by RENAM using one leased circuit. The traffic to the GEANT

network for Republic of Moldova it is routed through the eastern ring of the national backbone.

The western ring connects the NOCs from Cluj Napoca, Timisoara and Craiova to the main NOC

in Bucharest. The western ring is connected with the central ring from Cluj Napoca through Tg.

Mures to Bucharest. This topology reduces the costs for the entire topology and also provides a

very good backup scheme for the western ring.

It should be noted that the traffic to/from all NOCs is balanced through all links to make use of

the entire available capacity. However using this topology the main NOC have a total capacity for

the national network of about 5 Gbps and this put a big pressure on the international links.

All POPs are connected using Ethernet leased circuit that operates at 10 to 50 Mbps. The capacity

values were upgraded based on the traffic history of each POP; usually the POPs where

universities are located have now links that operate at 30 to 50 Mbps.

One of the most important milestones in the development of the national infrastructure was the

moment when the contract between RoEduNet and SC Telecomunicatii CFR was signed. This

contract stated that RoEduNet will be able to use the dark fiber infrastructure of the mentioned

company. In fact, RoEduNet can use one pair of fiber for 10 years; the total length of this fiber is

4150 km.

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