The
working
net

what you need to know
about your connection

Basic network access is critical to many daily activities for researchers – whether you are seeking information on the web, sending email messages, making voice and video calls in your work and personal lives. Over and above this, many research disciplines now require the exchange of substantial volumes of data across the network, and as this requirement grows it brings with it a need for greater awareness of some of the factors that can affect data-transfer performance. David Salmon, Research Support Unit Manager at JANET(UK), the UK’s research and education network, talks to JISC Inform about what you need to know to ensure you are getting the most out of your network.

Some research groups have considerable maturity in this area and are now adept at moving large volumes of data both nationally and internationally, but as their needs grow, and new disciplines begin to build larger-scale data movement into their working patterns, the requirement to achieve ever-higher network throughput is increasing.

Normal activities you do every day – such as the use of web and email – generate relatively small traffic volumes in comparison to the physical capacities of the network infrastructures they use. all these are low-level activities, added together with every researcher across the uK, the network has a lot to do. So it’s crucial that the network can handle the pressure, as well as leave enough headroom for the more intensive data work about this level

Nevertheless, there are issues that you need to understand to achieve high-throughput data transfers. So if you have a need to do this, how is it best approached ?

1. The first step is to make a quick assessment of the scale of the data transfers you wish to make. This is fundamental as defining your research work pattern leads directly to an estimate of the network capacity which you will need to support you work.

2. Once a pattern of work is defined it is straightforward to calculate the network capacity you will need to move one of your data sets of a given size over a given period of time.

3. Whatever the level of use, if you are expecting to undertake frequent transfers of large datasets, it would be wise to discuss your requirements with colleagues who support the network infrastructure at your organisation, and similar considerations will also apply at the remote end of your data-transfer.

4. As dataset sizes increase, you may find that the data-transfer rates you are achieving are not sufficient to move the data within the time required, and then you may require a more detailed analysis of the end-system capabilities and the intermediate network connections. Even if plenty of network capacity is available, it may be that the end systems are not powerful enough and don’t have the internal data-throughput needed.

5. Another service that may also play a role is a point-to-point network connection, sometimes called a circuit or lightpath. This provides dedicated capacity for projects and is typically used where this is a long-term persistent requirement for high-volume data transfers between locations. All the end-to-end and systems issues noted above still need to be considered, but there will be no other traffic on the link and that should help with performance.

6. Networks are also important platforms to support research on networking and network technologies – self-contained “overlay” networks can be built between research labs using circuit or lightpath services, and this enables you to connect your own equipment and manage the communications between your facilities without fear of interference or disruption to standard network services. You can then explore new networking concepts and protocols such as those funded through projects in the EU Fire and NSF GENI programmes.

At an even deeper level, once you have gained access to a dedicated dark-fibre facility you can do strategic research on photonics and optical systems. This is work which will lay the foundations for new transmission technologies and optical networking techniques leading towards future network capacities much greater than 100Gbit/s per wavelength, and more flexible approaches to processing and managing data transmission at the optical level.

These topics apply to researchers wherever they are supported within National Research and Education Network (NREN) environments globally, although there are differences of scale and emphasis between nations, and not all services and facilities are available in every country.

In the UK JANET supports high-capacity IP network services, Lightpaths, and provides a dark-fibre research platform, JANET Aurora.

For more information on your JANET connection, and how to make the most of it visit www.janet.ac.uk