First test on real fibre!

av Fredrik "Hugge" Korsbäck den 17 Nov 2015

This week we were able to get early access to the pilot-sites and a backbone fibre-span we will use to do acceptance-testing with. The span is between Stockholm (Tulegatan) and our new site in Västerås. In the middle of absolutely nowhere a couple of kilometers north of Enköping there is also a amplifier-site.

In Tulegatan there is a Juniper MX480 originating a 100G Coherent wave that goes straight into the ROADM (no transponders here as i mentioned earlier), then goes onto the line-fiber. It gets amplified in Enköping and then lands into another ROADM in Västerås straight through to another Juniper MX480 with a Coherent reciever.

The amplifiers neighbours. Power shortage is not to be expected.
The amplifiers neighbours. Power shortage is not to be expected.
EDFA Amplifier site, one in each direction.
The entrance to the amplifying station

After some struggle with a malfunctioning ROADM-card that didn’t pass any light in one direction this span is lit up and traffic is passing through without any problems.

The site in Västerås with ROADM in the top and the router in the bottom of the rack. Very temporary installation since the equipment is to be returned to Tulegatan in week 48
The SUNET branch-office in Västerås...
Incoming linefiber ODF
The sliding racks
The racks in these main-pops is sliding on the floor (to reach the backside). This is the solution for having the fiber and powercables follow the rack


When you work with fiber and especially in DWDM-related scenarios cleaning fibers is always of uttermost importance. Dirty connectors cause attenuation which can destroy the optical budget calculated on a link. Blowing in the ODF connectors and wiping the patch-connectors on your jeans is without any doubt the most effective way to make your fibres dirty. To illustrate this i uploaded our initial FiberScope-tests on both connectors in the ODF´s and on patches, some of them brand new. Nothing is clean until you have actually scoped it and verified, especially if its fresh from the factory.



Connecting fibres with connectors like this on a optical system does not only cause you attenuation but it could also damage both the ODF and the patch since the dirt can over time etch in the glass if unlucky.

Fredrik "Hugge" Korsbäck

Network architect and chaosmonkey for AS1653 and AS2603. Fluent in BGP