Title of Service: Backbone Network

Status of Document: This document describes the backbone network services offered in June 2011.

1. Introduction

  • The University Network Backbone is an Ethernet operating over optical fibre cables at 10 Gbps. It is arranged in a double star configuration with two central Cisco Catalyst 6509 core switches connected to 10 Cisco Catalyst 6506 edge routers providing over 200 separate optical fibre connections to college and department buildings.
  • Within a building, a Frodo distribution switch (Cisco Catalyst 3750) provides multiple service connections. Ethernet connections can be supported at 100 Mbps and 1 Gbps.
  • A separate Cisco Catalyst 6509 router provides a connection to the 10 Gbps link to the UK Academic Network, JANET, which gives connection to all Internet connections outside Oxford University.
  • The University network is behind a Cisco firewall. This runs in default permit mode with blocks being added for some known vulnerabilities.
  • The objectives of the service are to provide interconnection between all department and college networks and the external JANET network.

2. Summary of OUCS’s responsibilities

Hours of Service

2.1 The service operates at all times.

2.2 Operator cover is provided from 08:30 to 20:30 on weekdays. Periodic monitoring takes place outside these hours, and informal arrangements exist for staff to be called, but no funding is provided to make this contractual.

2.3 If a fault is notified between 09:00 and 17:00 on a working day, OUCS will commence investigation and correction within one hour (provided that no similar fault is also being handled by the same team). It must be noted that many Communications Rooms are under departmental control, and immediate access to these may not be possible.

2.4 If a fault is notified outside these hours, OUCS will use its best endeavours to attend the fault, but no funding is allocated to this purpose. It must be noted that access to departmental Communications Rooms may not be possible.

Serviceability Targets

2.5 It is intended, as far as is possible, to maintain service of all components at all times. As most failures are through external causes, no overall or individual serviceability targets have been set. Many outside faults involve unplanned civil engineering work, and it is not possible to impose contractual targets.

2.6 JANET(UK) (the trading name for the JNT Association, which has responsibility for the management of the UK’s Higher Education networking programme) advertises an at-risk time for the JANET network from 07:00 to 09:00 on Tuesdays. This is rarely invoked.

2.7 OUCS endeavours to carry out any work required during the Tuesday JANET at-risk period.


2.8 The Backbone Network is resilient to failure of either of its central switches. Failure of an edge router will cause the isolation of all sub-networks connected through it. Failure of the JANET router will cause loss of connection to the Internet.

2.9 Fibre optic routes between routers are duplicated, as is the link to the University departments in Headington. Links to individual departments and colleges are not usually duplicated and are vulnerable to damage.

2.10 The connection to the JANET network is duplicated as far as the JANET connection point at Reading. Resilience within the JANET network is in place and the responsibility of JANET(UK) and its contractors.

Alternative Facilities

2.11 No alternative exists to any of these facilities.

Hardware and Software Maintenance

2.12 OUCS holds lengths of spare optical fibre cable, and has arrangements for rapid response from a local cable contractor and a local civil engineering contractor.

2.13 The power supplies to the Communications Rooms containing the routers are protected by UPS equipment giving approximately two hours' standby. The University Estates Directorate has been requested not to carry out any work in these rooms without consultation with OUCS. Equipment in the OUCS building shares a UPS with other essential services, giving approximately 30 minutes' standby. OUCS has a separate electricity feed from an adjacent University building, which can be brought into use to maintain this and a limited number of other essential services in the event of a localised outage of the main power distribution circuits in the OUCS building.

2.14 The Cisco router and firewall hardware is maintained by Cisco, whose contract specifies a next business day call out. OUCS Network Control team carries a spare edge router and parts on-site and can swap out faulty equipment.

2.15 Software updates to the Cisco equipment are supplied by Cisco and applied by the OUCS Networks team. Except in the case of a major system fault or the risk of a major breach of security, at least one week's notice will be given of down-time on any part of the network and departments and Colleges affected will be informed. Except for such vital fault corrections, software updates should not take place more than twice a year and should cause less than 30 minutes' downtime on each router.

2.16 Maintenance of the link to the JANET network is the responsibility of JANET(UK) and its contractors.

System Development

2.17 There is no scheduled development time.

Administration and Support

2.18 Connection to the Network Information for departments and Colleges wishing to make new connections to the backbone network is given at http://www.oucs.ox.ac.uk/network/connect/.

2.19 Notification of faults, outages, etc is circulated on the mailing list itss-announce@maillist.ox.ac.uk

2.20 Fault Reporting

Faults should be reported to OUCS Network Control on (2)73286. An answering machine receives calls outside office hours. OUCS will liaise only with department and College computing officers; no end-user networking support is provided.

Education and Training

2.21 Not applicable.

3. Summary of clients' responsibilities

3.1 Departments and colleges are responsible for maintenance of their own internal networks and for liaising with OUCS over their connection to the backbone.

3.2 The client will provide contact details of the person with responsibility for the local network with whom OUCS can liaise over faults, upgrades, etc.

4. Overview of Service

4.1 It should be noted that the University pays the connection charges for the JANET network from the Infrastructure fund.

4.2 The cost of new connections to the backbone network falls on the department or college requiring that connection.

4.3 Upgrades to the connections between departments, colleges and the backbone may be required as part of periodic upgrades to facilities. The University will assign funding responsibility as it deems appropriate.

5. Premium services:

In addition to 4.2 above, work above and beyond the normal maintenance and connection of the existing network, e.g. to non-University units or premises, may be charged for but this would be part of a discussion between OUCS and the project or unit.

6. Logging

Logs are kept of system messages from devices such as routers and switches. Logs are retained for 12 months.