Created on 26 July 2012
Please note: This Information Sheet may be outdated
Schools’ broadband usage is continuing to increase, as it has done annually in the 10+ years since RBCs were formed. Demand for transit bandwidth doubles in somewhere between 12 and 18 months. BT and other operators are currently rolling out a range of technologies to deliver higher speed broadband services including both fibre to the cabinet (FTTC) and fibre to the premise (FTTP) solutions. The bulk of BT’s next generation broadband deployment to date is based on FTTC, and the company is investing £2.5 billion to reach two-thirds of the country with its broadband programme by 2014. Many areas have already been upgraded with FTTC services, with many more to follow
This paper illustrates the possibilities FTTC offers to schools, working in partnership with local authorities and regional broadband consortia (RBCs). Trials within embc, the RBC for the East Midlands, indicate that FTTC is potentially a very cost-effective way to upgrade schools’ connectivity to accommodate their ever increasing demand for broadband, whilst maintaining on-network access to the safe and secure environments that schools require.
Traditionally, homes and businesses are connected to their serving telephone exchange with copper telephone lines running via a street cabinet, the green cabinet visible at the side of the road. With fibre to the cabinet (FTTC) technology, the copper lines between exchange and street cabinets are replaced with fibre-optic cable. Fibre-optic cable can support much higher speeds than copper telephone lines. An additional advantage of fibre-optic cable is that its performance is not affected by distance, unlike copper, where speeds degrade with distance (so, in general, the further a premise is from its serving telephone exchange, the slower its broadband). The following diagram illustrates how FTTC services can be deployed to connect schools to their serving local authority or RBC network. Links from telephone exchange to street cabinets are replaced with fibre-optic cable and the copper sub-loop is used for the final connection to premises:
Current FTTC services can provide download speeds of up to 40Mbps and upload speeds of up to 10Mbps. Further developments will make up to 80Mbps services possible from Spring 2012. Openreach, the division of BT responsible for managing and upgrading the access network connecting customers’ premises, provides a useful overview of fibre broadband technologies on its website.
It is very important to distinguish between FTTC services provided by local authorities and RBCs as part of a managed wide area network from services available for individual purchase by schools from commercial providers. RBCs and local authorities provide bespoke, managed broadband networks offering safe, secure, high-performance, education-specific broadband connectivity and services across an entire locality or region, far above and beyond a connection to the Internet. More information on the difference between an Internet connection and an RBC or local authority managed broadband service is available in NEN Information Sheet 1, Broadband Service Requirements.
A key advantage of an RBC- or local authority-provided broadband connection is its capability to support schools working in clusters. Such working necessitates a connection into a managed wide area network, not just a connection to the Internet, to allow schools to operate as either a single local or wide area network or to enable one school to provide the support for the cluster as a whole. Such schools have to be part of a managed network to operate successfully in this way and the resulting demands on connectivity are much more symmetrical, i.e. they require significant upload as well as download capacity. Similarly, for remote back up or cloud backup and synchronisation, the demands are again more symmetrical.
The objective of embc’s trial was to explore whether FTTC could provide satisfactory connectivity to deliver embc’s range of on-network services for schools, including remote management and support, cluster working and centrally provisioned Internet filtering. Planning for the trial began in spring 2011 when it was identified that a number of BT exchanges in the embc area had or would soon be upgraded to deliver FTTC services (embc’s network architecture and existing connectivity for schools is based around BT exchanges).
The Hinckley exchange was chosen for the trial, as it was already an important part of the embc network. Five primary schools were identified to take part in the trial, all of which had 2Mbps symmetric (same download and upload speed) broadband network connections delivered over copper telephone lines. All five schools continued to receive the same embc services and support during the trial as previously; there were no service delivery issues or changes resulting from the change in connectivity technology used: a wholesale variant of FTTC to provide on network connectivity.
As stated earlier, FTTC is an asymmetric technology, offering higher download than upload speeds, and it is also dependent upon distance from the serving street cabinet, with the highest speeds only achievable over short distances (BT will not install FTTC domestically if less than 15Mbps can be achieved on the line). As a consequence, the speeds achieved via FTTC in the five schools varied, but all benefitted from very significant uplifts to their previous upload and download speeds of 2Mbps. Measured FTTC download and upload speeds were as follows:
|Upload speed (Mbps)||Download speed (Mbps)|
These variations in speed underline the important role of the RBC or LA in testing and commissioning FTTC, to ensure it was appropriate for each schools’ requirements. Distance and speed limitations mean that FTTC is not an appropriate technology for every school, but it can nevertheless offer a very cost-effective upgrade from copper telephone lines where it is applicable: wholesale install and annual rental prices for FTTC are significantly lower than alternatives, while offering much higher upload and download speeds.
Monitoring showed that all five schools made immediate use of their additional broadband speeds and capacity, with peak download speeds reaching around 15Mbps (limited by the routers employed in the schools rather than the available capacity), a significant figure for comparatively small schools. No issues were encountered with the quality of connections during the trial, with the new FTTC services providing reliable and stable performance. Upgrades to the routers used in the schools were necessary to take full advantage of the faster speeds available, these were provided by embc.
Future FTTC upgrades (to provide up to 80Mbps download speeds) may mean the technology may in time be applicable to larger schools too; embc will conduct tests as and when these services become available to ascertain their suitability for this. This again underlines the importance of the RBC or local authority as an intelligent, informed commissioner of services. RBCs and local authorities’ deep understanding of schools’ broadband usage profiles ensures new technologies such as FTTC are only applied where it is appropriate and beneficial to do so, as part of the strategic delivery of managed broadband services for schools.
Just like current generation residential broadband services, wholesale FTTC services are asymmetric, in that they provide higher download than upload speeds. For applications like streaming video this does not create any difficulties, as services like these are dependent upon download rather than upload speeds to work properly. Much current Internet usage follows this pattern, where more data is downloaded than uploaded, meaning that FTTC’s lower upload speed is very unlikely to cause problems for the majority of users for the time being. It should also be noted that all five schools in the embc trial benefitted from a significant uplift to both upload and download speeds.
But Internet usage continues to change and develop as new services and applications become available. Some of these may in time require higher upload speeds as well. For example, highquality videoconferencing requires significant upload as well as download speed, as video and audio streams travel in both directions between connected sites. Similarly, the growth in the availability and popularity of “cloud” services (where applications and data are uploaded and stored remotely for access and sharing online) can require significant upload speeds to ensure content and data created locally (for example, photos, video or music) can be uploaded quickly and efficiently from the local premise into the Internet “cloud” for access from anywhere. RBCs and local authorities continually monitor such developments to ensure that broadband services for schools keep pace with changing requirements.
It is still however true that most schools’ broadband usage is for research or viewing content and whilst videoconferencing and cloud applications are being used in schools, typical usage profiles show significantly more downstream than upstream usage. However, schools equipped with symmetric 2Mbps broadband services are able to benefit from the greater upload and download speeds FTTC technology offers, especially in the light of its low cost and the higher speeds that may be achievable in future.
It is also worth noting that the latency (the delay in transmitting data) measured by embc was typically 7 ms for the round trip between the school and the embc data centre. While this is about double that expected for a fibre circuit it is around the same as measured for other dedicated copper connections such as LLU. This level of latency is better than that required for voice and videoconferencing services.
The FTTC opportunity underlines the importance of local authorities and RBCs in brokering effective connectivity solutions for schools. The embc FTTC pilot builds on previous innovations demonstrated in the previous local loop unbundling case studies project, in which embc was also a participant. The fact that FTTC will not be universally available and is not an appropriate solution for every school, both in terms of usage requirements and FTTC’s variable, distance-dependent speeds, demonstrates the importance of RBCs and local authorities acting as an intelligent customer on behalf of schools, offering a range of connectivity options and choices.
RBCs and local authorities understand and can aggregate their customers’ requirements, meeting them using the broader market to deploy technologies that provide the best balance of capability, performance and cost in particular areas. The technical expertise and buying power of RBCs and local authorities acting on behalf of schools enables the effective and timely updating of services to take advantage of new technical opportunities. A thorough understanding of product and technology roadmaps and lifecycles is key to a strategic approach to broadband provision, keeping pace with continually increasing requirements for speed and performance.
Openreach’s prices are regulated meaning that they cost the same irrespective of the supplier. Price advantage through RBCs comes about through aggregation, supporting the enabling of exchanges as local points of presence (POPs), offering shorter and cheaper tail end circuits for schools. It is this aggregation of demand, supporting the establishment of local POPs that enables better and cheaper like for like services.
RBCs and local authorities have a successful track record in this regard, having grasped the nettle of complex connectivity provision to deliver high performance, cost effective, scalable infrastructure and services for schools over many years. It should be noted that RBCs and local authorities have been delivering superfast services already for many schools for several years, with many secondary schools now having 100Mbps connections.
The expertise within RBCs and local authorities means that technologies like FTTC can be deployed rapidly and effectively to improve performance and reduce costs while maintaining access to a full set of education-specific broadband services and support. This ensures that as many schools as possible are able to participate fully in the UK’s superfast broadband future.