Netnod Internet Exchange i Sverige

Netnod Internet Exchange in Sweden AB (Netnod) is the largest operator of Internet exchange points in Sweden. Netnod is a fully owned subsidiary of a foundation (Swedish: Stiftelsen för Telematikens utveckling), also known as the TU foundation. The TU foundation and Netnod was founded in late 1996 and became operational in 1997.

History

The predecessor to the TU Foundation / Netnod was the D-GIX, an Internet exchange point that was established at the Royal Institute of Technology (KTH) in Stockholm and operated by KTHNOC. D-GIX had been one of the first IXes that were established in Europe, and quite successful at that. In 1996 a report by a committee, Swedish: Internetutredningen) had listed infrastructure that was critical for the operation of the Internet in Sweden. Among the critical infrastructure listed was a robust and reliable Internet exchange. A number of factors led KTH as well as the Swedish ISPs to conclude that a separate legal entity would be a better operational format. After legal consultations, and seeing that the Swedish government seemed keen to play a role in the infrastructure operation, the Swedish ISPs decided to found the TU Foundation. The capital ironically came from a government set up foundation, the Knowledge Foundation, KK-stiftelsen, one of the largest Swedish research foundations. The idea behind the ownership model with the foundation was that it would guarantee independence from the operators as well as from the government. Linkage to the operational community comes from the fact that the Swedish university network SUNET appoints one of the board members, and the Swedish Operator Forum appoints two of the Netnod board members.

The TU-Foundation established the operational company Netnod to run the IX. In the beginning Netnod had no staff of its own and all operations were outsourced to the Swedish military. In 2001, Netnod created fully owned a subsidiary called Autonomica. Autonomica was to run the operations for Netnod (who then as well as now, do not have any staff of its own) as well as run the i.root-servers.net on behalf of NORDUnet and do Internet related research. In the beginning the staff mainly focused on DNS and management and the operations considered to be outsourced to the military. However, finally in 2002 Autonomicas staff grew considerably and the contract with the military was ended. Operations is today done entirely by Netnod staff.

Redundancy and physical security

From the beginning, as was cited in the Internetutredningen report, the IX operated by Netnod was considered as critical national infrastructure. Netnod therefor in 1997 agreed with the Swedish telecommunications regulator to locate the IX equipment in government operated secure telecommunications bunkers. In addition, it was agreed that operations should not be dependent on Stockholm alone. Netnod therefor established IXes in Stockholm, Gothenburg, Malmö and Sundsvall. All of these locations were located in the government bunkers, as opposed to co-location facilities as the case in most other countries. The exchanges are independent and not linked, so operators connected in one city will only see other operators connected in the same city. However, most of the larger Swedish providers are connected at all four cities. Netnod since 2004 also operates an IX in Luleå.

Technology

The first D-GIX was a 10 Mbit/s switch. By the time D-GIX was replaced by Netnod the exchange point consisted of two FDDI switches in Stockholm and one was also installed in Gothenburg. Around 1998, the FDDI circuits were filled and traffic was heavily impacted by head-of-line blocking. At a Swedish Operator Forum meeting the alternatives were discussed. The options were basically two. The new Gigabit Ethernet standard, and a standard developed by Cisco called Spatial Reuse Protocol, SRP. The decision to go with SRP was basically based on the fact that at the time Gigabit Ethernet and SRP had roughly the same cost. SRP also did not have the issue of head-of-line blocking, and SRP had a larger MTU size than what Gigabit Ethernet had at the time. So the Swedish operators decided that Netnod should implement SRP. The SRP rings installed were running at 2x622Mbit/s in each city.

It wasn't soon until the 2x622Mbit/s was not enough. Netnod then proposed to the operators to migrate to SRP 2x2.5Gbit/s, which was also installed. The larger operators all moved to the new SRP rings, but the smaller operators wanted a cheaper method. By 2000, Gigabit Ethernet was starting to become mass-market and the price had dropped compared to SRP. Gigabit Ethernet had by then also implemented jumboframes. Netnod said they were willing to implement Gigabit Ethernet, but wanted 8 operators to promise to sign up to cover the costs. In the mean time some operators went off and created an alternative, Ethernet based IX, SOL-IX. However, Netnod managed to get their 8 customers quite fast and built out Gigabit Ethernet at all cities. For 2 years, the old FDDI exchange (that was still operational) was connected to the Ethernet switches, but by the end of 2002, all SRP and FDDI equipment had been migrated away from.

Today the Netnod platform consists of single chassis Gigabit Ethernet switches at each location. Operators are connected with either 1Gigabit or 10Gigabit Ethernet, with a clear trend of operators moving to 10 Gigabit Ethernet connections.

References

• The book, they built Internet in Sweden(Swedish: De byggde Internet i Sverige)

External links

• Netnod web site
• Euro-IX