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Section 3 – Appendix A Section 3 ICT Infrastructure Purpose The purpose of this section is to provide an insight into the basic form and type of ICT infrastructure currently available. It is intended that managers may then use this information when producing a workable networking and hardware policy for corporate and specialist departmental systems. Although the technical aspects of ICT infrastructure are the responsibility of ICT specialists, managers and accountants have a management and developmental role to play, and will therefore need to understand the basics. Introduction 01 Continual advances in technology have made selection decisions for computer hardware more complex. Until recently, large corporate databases supported the acquisition of large corporate servers in the form of mainframe computers, leaving many smaller and more specific applications to be catered for by smaller departmental machines or standalone PCs. Such machines were often totally controlled at the user end and became networked to other similar machines for the purposes of communications and data transfer. March 2003 Volume 10 – Information and Communications Technology 02 Historically, the larger ICT resources were held in central locations due to their high cost and specification. More recently the general trend, linked to changes in technology and cost, has been to decentralise computing power, providing technology and processing power directly under the control of service managers. The information required to make informed decisions on the acquisition of ICT services has therefore switched to the same managerial control level. To achieve proper corporate management of the ICT infrastructure, a corporate group or an individual usually takes on the responsibility for determining direction for ICT services, in line with the ICT strategy (see the ICT Strategy section). This helps ensure that maximum benefit is obtained from the investment made. 03 In spite of this decentralisation, corporate servers still cannot be dismissed as they play an important role in the overall provision of an infrastructure strategy by virtue of lower support cost and better security benefits. There is also now a trend for some organisations to use smaller numbers of servers in a central location, as this makes them easier to manage and helps in disaster recovery. 04 The provision of the right infrastructure will allow the user to take full advantage of future advancements in technology. Open Systems 05 The dynamic and complex environment of business in general and the economic and political pressures for change in public service management meant that managers were no longer prepared to be locked into single hardware and software solutions. The relative investment expense of proprietary information systems and their failure to interoperate used to hold organisations hostage when suppliers delayed new technologies and upgrades. The move to open systems has helped to overcome these problems. Financial Information Service Section 3 – ICT Infrastructure 06 The concept of open systems is taken for granted now as the manner by which systems are able to interact internally with their subsystems, and externally with their environment. 07 The development of open systems resulted in hardware and software products that were in some way standard, as opposed to proprietary systems associated with one manufacturer. In theory, this means that the best hardware platform and the best software solution for a particular need can be selected independently from one another. However, detailed planning and project management are essential if successful implementations are to be achieved. Logically, these should have followed a full options appraisal, including cost benefit analysis. 08 Along with the migration towards open systems, there has also been a tendency to move away from traditional mainframe systems to systems running on smaller and cheaper mid-range processors utilising for example UNIX, Sun or Windows. These systems run on many different makes of hardware, although the portability from one machine operating system to another must be thoroughly checked. 09 Network processors have now been developed that match the capacity, speed, reliability, durability and cost of the mid-range processors. This has prompted many users to assess if the majority of their corporate needs can be met by networking. Communications Networking 10 Networking is a logical extension of the open systems concept. It is concerned with communication between systems and ultimately the exchange of data; for example, sending and receiving e-mails or sending a print request to a networked printer. March 2003 Volume 10 – Information and Communications Technology 11 A sound communications structure is essential for the use of e-mail, both internally and externally through the Internet, and for other technologies such as document image processing. These subjects are considered more fully in the Applications section. [Perhaps, provide a hyperlink.] 12 The problem of how to link the variety of systems that may run within individual organisations is one for the ICT specialist. It is, however, important that managers and users have an appreciation of the potential for interconnectivity and how business benefits can be derived from such linkages. Due to the tendency to decentralise computing resources, networking is crucial to ensure that corporate data can be accessed and shared by those who need it. 13 It is important that networking is controlled corporately to ensure usage and compatibility of networks is maintained. Management of the network infrastructure, and its data, is vital to ensure an efficient flow of information. Central monitoring of PC servers, network traffic and overall performance should be carried out on an ongoing basis. 14 With the gradual reduction in the relative cost of new technology and the increasing number of compatible devices in a localised area, a greater need arose for an inexpensive means of linking ICT equipment together in the form of local area networks (LANs). Local area networks (LANs) 15 LANs are now a familiar part of the office environment. They allow computer equipment on a given site, or in an office, to be linked. The main advantages for users, is that all authorised users have access to shared files, software and network resources such as high speed laser printers, colour printers, plotters, scanners and fax modems - where purchases for each individual user could not be justified. Perhaps, more importantly, a also LAN allows security issues such as access, virus protection Financial Information Service Section 3 – ICT Infrastructure and back-up to be coordinated at one source rather than relying on individual users. LANs also have the advantage that staff can be moved easily within an office. 16 Network managers face difficult challenges. They must provide network access to virtually every employee, build infrastructures that can work with a broad range of high-speed LAN technologies and manage systems with unpredictable and changeable data flows.[Not sure what point we are making. Are we meant to feel sorry for network managers, or are we saying that the work is complex and has to be done correctly] 17 Also, a LAN has the benefit of providing a means of integrating non-compatible computers. Many offices today have a mix of PCs and perhaps UNIX and mainframe workstations. A network can solve the problem of incompatible hardware and operating systems by translating all data into a form that can be understood and used by the different types of computer in the office. 18 There are two broad types of LAN: peer to peer client/server. Peer to peer LANs 19 Peer to peer LANs connect each PC either by direct cabling or through a central PC and allow the sharing of resources such as peripheral devices and storage, as shown in the diagram below. There is no dedicated fileserver as each PC effectively shares that responsibility. This arrangement is generally used to connect a small number of PCs, as it is a cheaper alternative to a client/server arrangement. The main disadvantage is the slower speed of operation, as each PC is performing some of the functions of the server. As a peer to peer network has no dedicated computer for shared data (fileserver), each user determines the resources they wish to share with others. March 2003 Volume 10 – Information and Communications Technology Peer to peer-based LAN Desktop PC Peer to peer Personal printer Desktop PC Desktop PC Desktop PC Personal printer Client/server LANs 20 Client/server LANs consist of a number of PCs connected to a central fileserver which stores shared data and applications software, as shown in the diagram below. This fileserver administers the network and controls network traffic, and all connected PCs communicate through it. The main advantages of this arrangement are the speed of operation and the central control. The disadvantages are the setup and running cost and the inability to share the hard disk storage on one PC with another. Financial Information Service Section 3 – ICT Infrastructure Client/server-based LAN Desktop PC Client Personal printer Desktop PC Client Desktop PC Client Server Workstation Client Personal printer Network cabling 21 The way in which cabling is laid for LANs is the responsibility of the ICT specialist. Briefly, however, there are two main types: token ring and Ethernet. Both are sophisticated network topologies allowing the sharing of computing resources. 22 A token ring LAN is a group of computers connected in a loop. Each computer can send a signal along the loop, after first receiving permission to do so. The permission is in the form of a token attached to the data being sent. Only one computer at a time may have control on the network and the signal sent will travel from one computer (or networked peripheral) to the other until it reaches its initiator. An illustration of a basic token ring topology is shown in the diagram below. March 2003 Volume 10 – Information and Communications Technology Token ring LAN Desktop PC Client Desktop PC Client Token ring Server Workstation Client Networked printer Client 23 Desktop PC Client Personal printer Ethernet LANs use a bus topology in that all the network devices are connected to a single long cable. Any device can send a signal along the cable, which all the other devices will receive. Data is only sent after the sending device listens to the network to see if it is already in use. Ethernet is currently the de-facto standard for LANs. An illustration of a basic Ethernet bus topology is shown in the diagram below. Financial Information Service Section 3 – ICT Infrastructure Ethernet LAN Server Desktop PC Client Networked printer Client Ethernet bus Workstation Client 24 Desktop PC Client These topologies introduced new requirements for wiring and saw the development of Category 3 (Ethernet) and Category 4 (token ring). Within the last few years, corporate ICT has become almost completely LAN based and a new cabling standard (Category 5, or structured cabling as it is more commonly called) has been introduced to provide higher data transmission levels and to provide for future advancements in communication technologies. 25 Gigabit Ethernet is a technology for Ethernet networking at a speed of one gigabit per second. It is mainly used for large, high capacity backbone networks, but it has started to be introduced for desktop PCs where high capacity is required for certain specialised applications. 26 Organisations may experience problems when introducing a LAN; especially where a large amount of computer based equipment already exists. Typical problems encountered may be that: March 2003 Volume 10 – Information and Communications Technology previously expensive software solutions may become redundant; major new software may become necessary; training may be necessary for staff with responsibility for supervising and administering the networks; physical installation problems with new cabling may arise, such as the discovery of asbestos. Wireless LANs 27 A wireless LAN uses wireless technology (usually Wireless Fidelity – WiFi), rather than cables, to provide the link between users’ PCs and the network. There are currently nearly 4,000 WiFi ‘hotspots’ in the UK – areas of approximately 30m radius that allow people to access the Internet and corporate networks wirelessly. They are mostly in airports, hotels, conference centres and other public areas. 28 However, as the cost of the technology has fallen, wireless LANs are increasingly being installed in homes and offices. They are easy to install and use, and can be installed in old buildings or other locations where cabling is difficult. They improve flexibility by removing the need for cables when staff log on to the network. This is particularly beneficial for employees who work remotely and are only in the office occasionally, or who may be moving around the building. 29 Despite these benefits, wireless LANs do have some disadvantages when compared to wired networks. Data transfer speed will be slower, as all users of a wireless base station will have to share the available bandwidth. Security is also a major concern. A WiFi hotspot has a radius of 30m, including through walls, so the network will be accessible outside the building. Encryption must be used, and updated frequently. Wide area networks (WANs) 30 Where the hardware is not located on a single site it can be linked together by use of a wide area network (WAN). WANs are less common and more expensive than Financial Information Service Section 3 – ICT Infrastructure LANs but operate on the same basic principles except that each site is linked together. 31 A WAN can exist on a single site; the distinction between a LAN and a WAN is actually determined by the geographic location of the devices being connected and hence the length of cabling required. 32 Organisations often have a number of LANs that may be based on departments or sections. Once an appropriate corporate communications infrastructure is in place across the organisation then LANs will be able to interact with each other and the full associated benefits of a WAN will be available. Communications links 33 Structured cabling is generally acknowledged as the approach needed to ‘future proof’ infrastructure. Cabling has always been the longest-lived element of any system. Accordingly, there may be good reason to introduce infrastructure that is over-specified for the original system. Until recently, buildings would have different cabling for different communications systems. Structured cabling can replace all this with a single system for voice, data and video covering the whole site. 34 Structured cabling can also go some way towards easing an organisation’s cabling problems by using a single cable to carry all transmissions. This cable passes through all of the offices to be served by a network, enabling all existing and future devices to be connected to it. Depending on the size of the building, it may be necessary to add ‘repeaters’ to extend the capability of the cabling, as some information degradation occurs over long cable runs. The use of a communications ‘backbone’ (a cable running through all sites) can allow many servers and workstations to be physically attached to it, whilst logically isolating each individual network through software control. March 2003 Volume 10 – Information and Communications Technology 35 In addition to the cabling within the organisation, communications links to the public telephone network and the Internet must also be considered. The development of broadband infrastructure, including fibre-optic cabling, digital exchanges and satellite communication systems, together with the increasing convergence of computer and communications technology, is beginning to improve the efficiency and cost of computer communications. This has stemmed from the deregulation in the telecoms industry, which has prompted a large investment in digital infrastructure. 36 Laser communications links can also be used as a substitute for cables, for example for LAN to LAN links between buildings and where physical barriers such as roads restrict the use of cable. Line of sight is required, and the link can be affected by atmospheric conditions such as fog or pollution. However, laser provides a high speed connection that can be set up quickly, and as the beam is very narrow it is more secure than other wireless technologies. 37 Voice over IP (VoIP) technology can be used to make telephone calls over IP-based networks (i.e. over the internet or over an internal LAN –like using Broadband at home). This technology uses much less bandwidth than traditional telephony, and is therefore cheaper, particularly for long distance calls. It also has the advantage of reducing the amount of infrastructure needed, as a single network can be used to carry both voice and data. Broadband infrastructure 38 Most communication between machines is still carried out over public telephone lines by the use of modem and telecommunications software. However, this means of communication is limited by the quality and speed of data transmission coupled with the occasional unreliability of the telephone network. UK telecoms operators are increasingly rolling out broadband infrastructure, and this can now alleviate the problems with the quality [Is quality the right word, as speed an capacity Financial Information Service Section 3 – ICT Infrastructure improvements, don’t necessarily lead to improved quality.] of data transmission, by increasing the speed and volume of data that can be transmitted. 39 The term ‘broadband’ refers to telecommunication in which a wide band of frequencies is available to transmit information. This allows information to be sent on many different frequencies or channels simultaneously, allowing more information to be transmitted in a given amount of time (just as more lanes on a motorway allow more traffic). Although definitions vary, broadband is often classed as data transmission at speeds of 256kbit/s or more (about “x” times faster than using a standard telephone line and modem). The main broadband technologies are outlined below. Leased lines 40 A leased line (or dedicated line) is a permanent connection between two sites, rented from a telecoms carrier for private use to interconnect different geographic locations within an organisation, or to connect an organisation to the Internet. Speeds can vary depending on the organisation’s needs. At a corporate level the per capita costs are reasonable, but for individuals who work away from their main base the costs are excessive. In response, the market has begun to provide lower cost solutions such as virtual private networks (VPNs) and other broadband technologies. 41 A VPN uses public telecoms infrastructure, such as the Internet [Do we mean the Internet, or telephone lines?], to provide remote offices or individuals with secure access to the organisation’s network by means of ‘tunnelling protocols’, which encrypt data at the sending end and decrypt it at the receiving end. This provides the same capabilities as a leased line, but at a lower cost. ISDN 42 ISDN (Integrated Services Digital Network) is a technology for digital transmission over ordinary copper telephone lines, and allows data to be transmitted at speeds up March 2003 Volume 10 – Information and Communications Technology to 128kbit/s (about half the speed of Broadband.) This is much faster than using a normal phone line for Internet access, and allows applications such as video conferencing, but ISDN is not a true broadband technology and is being superseded by higher speed DSL services. DSL 43 DSL (Digital Subscriber Line) is a technology for providing broadband access over ordinary telephone lines. Unlike dial-up connections and ISDN, DSL provides continuously available ‘always on’ access. It is faster than ISDN, and much cheaper than a leased line connection. The availability of DSL was initially limited but is now increasing. 44 The most common version of DSL is Asymmetric DSL (ADSL), so called because more bandwidth is available for downloading data than for uploading data. This is generally used for Internet access by residential users and small businesses, where the volume of data downloaded is usually much higher than that uploaded. It could also be used for connecting homeworkers. Symmetric DSL (SDSL) provides equal bandwidth in each direction, and is aimed at the business market. Fibre 45 The most efficient form of broadband access is to extend fibre-optic cables all the way into the organisation’s premises. This provides extremely high capacity, at speeds up to 100 times faster than DSL. However, it is also the most expensive method, as costly new cables must be laid, and this will limit its usage for the foreseeable future. Fixed wireless access 46 Fixed wireless access is a technology for providing connectivity through wireless radio instead of traditional copper or fibre. Despite the government’s efforts to issue spectrum licences and encourage development, the technology is not widely available Financial Information Service Section 3 – ICT Infrastructure in the UK. However, it may eventually find a niche in rural areas where it is difficult to build physical broadband infrastructure. 3G mobile technology 47 The main UK mobile companies are introducing third generation mobile networks (3G). 3G technology provides much higher bandwidth than previous mobile technologies, allowing new services such as video calling and Internet access via mobile devices. Since the technology is just emerging and is not yet available in all areas, most organisations have yet to consider how they might use it. However, this technology has significant potential for urban authorities (connectivity is unlikely to spread to rural areas). 48 GPRS (General Packet Radio Service) is a ‘2.5G’ mobile technology that provides a higher bandwidth than standard GSM mobile services. It has been widely used for data services such as Internet access and e-mail via mobile phones, although it is likely to eventually be replaced by the higher bandwidth 3G technology. Other communications issues 49 It should be noted that communications involves much more than internal networking of computer equipment. Modern office equipment facilitates communication worldwide, with other organisations, and with other departments, divisions or sections of an organisation. 50 Communications technology also gives the opportunity to decentralise mainframe applications, and facilitates the much wider use of PC applications in the production and publication of information. It allows different users within an organisation to access shared applications, such as diary management applications and other office packages. It also facilitates the growing trend towards homeworking, as users can gain remote access to the organisation’s network from home, via an Internet connection, and can use the organisation’s applications in the same way as office- March 2003 Volume 10 – Information and Communications Technology based workers. (See the Mobile Government section for more information on home working.) Servers 51 Placing major corporate packages on individual departmental servers has a number of advantages. This approach not only allows the organisation to respond to local computing needs, rather than those of the centre, but also promotes the concept of ownership of the core corporate systems amongst the departments concerned. 52 Seting up local departmental servers (whether they are physically located in departments or in a central ICT suite) allows them to be upgraded according to departmental needs. Usage, performance and trends can be monitored more easily, and consequently this can avoid the arguments that one department is subsidising the computing costs of another. 53 Introducing devolved computing can provide better resilience than using a central facility. Should either network or hardware problems prevent access to the central computer installation in an organisation without departmental servers then all services will be impaired. Should a departmental computer go down then the rest of the organisation will still function normally. [I thionk this paragraph needs rewoeding.] 54 The existence of a number of servers on a corporate network enables the backing-up of data across the network on-site for disaster recovery. Having several similar servers on the network provides continuity of service in the event of problems with an individual server. The ability to provide in-house disaster recovery could provide some savings as opposed to buying in this type of service from outside. Back-up media should of course be stored off site to provide data security in the event of fire or other physical damage to the site. Financial Information Service Section 3 – ICT Infrastructure 55 Some improvements in user response times can be achieved by splitting the corporate systems between a series of departmental boxes[What does this mean?]. Routines requiring the sorting and extraction of departmental data may be run more quickly on a departmental database mounted on a local server rather than a central one. Again the existence of departmental servers means that heavy use of local hardware will not impact on performance of servers held in other departments. The sizing and performance issues on the local server therefore becomes a departmental responsibility, providing it dovetails in with corporate requirements. 56 By strategically siting the local departmental servers around a corporate network, potential bottlenecks can be avoided and network performance improved. This is of particular relevance given the likely increase in both the quantity and size of data packets likely to be transmitted over the network in the future. 57 With the move towards running critical applications on networked systems, the need has arisen for systems that are continuously available. These systems and the software and strategies around them look to reduce or eliminate downtime owing to hardware and software failures. A balance needs to be struck between increased availability and the corresponding increased cost in time, money and effort. Specifications 58 Individually personal computers (PCs) are relatively inexpensive but collectively they make up a significant investment. As with any type of procurement it is important to make informed decisions regarding specification. An organisation should therefore specify the standard build requirement for its networked components and PCs as part of its ICT strategy or, alternatively, specify and purchase all PCs centrally. 59 Agreed standards are likely to consider: March 2003 Volume 10 – Information and Communications Technology 60 maintainability reliability compatibility upgradeability quality supplier support individual component specifications firmware social and environmental factors health & safety. The extent of consideration over specifications is also likely to be a function of cost and how key the component is to the functioning of the network and ultimately the business. Network Computers (Workstations) update needed 61 Network computers can be defined in a number of ways. In its simplest form a network computer refers to a terminal, a “dumb” PC that runs its applications from a central server. One advantage of this is that large organisations can use cheap terminals that are not worth stealing while the expensive servers are locked away. It also enables IT administration and support costs to be reduced, while users are still able to work with the Windows interface and benefit from all of a PC’s functionality. Software 62 The move to open systems, by definition, provided greater flexibility in terms of potential software suppliers and consequently a greater choice of applications. It is Financial Information Service Section 3 – ICT Infrastructure crucial that software provides what the organisation really needs. Important considerations will include: 63 the need to meet statutory reporting requirements general output produced and flexibility of reporting resources required to maintain the system interfaces with other systems ease of use meets business objectives. Software packages are available for a wide range of functions, from the vast corporate systems on which the whole organisation depends to simple PC based solutions: corporate systems include such functions as the general ledger which all areas of the organisation need to access. Such systems will be likely to be controlled centrally and will determine the requirements for other smaller systems in terms of interfacing etc; departmental systems are those that are mainly used by one department or section. Such a system may need to interface with the main corporate systems; office systems are usually based on PCs and include applications such as word processing and spreadsheets. 64 Clearly, there is a close link between all these systems. A networked PC will be used to run office systems as well as to access departmental and corporate systems. 65 Investment in software in many organisations will be substantial. Managers will wish to ensure that licences are purchased only for those PCs that are used to gainaccess to the system, and that some hard evidence is available which demonstrates that the organisation is abiding by the licence agreement. To provide this facility some form March 2003 Volume 10 – Information and Communications Technology of software tracking may be considered necessary. Packages are available which can monitor software usage and provide information on the minimum number of licences that will be required. 66 Open source software (OSS) – software for which the source code is made freely available, allowing anyone to use the software or create a new version – is currently attracting interest and government funding, for example through the second round of E-Innovations funding. One E-Innovations project, led by Birmingham City Council, will create an ‘Open Source Academy’ to research OSS and encourage its adoption by local authorities. This is intended to promote interoperability and provide efficiency gains and cost savings by reducing duplication of work. More information is available from the Local E-Gov website. 67 See the Applications section for more information on software.[Hyperlink please.] Summary 68 Managers need to give careful consideration to an organisation’s ICT infrastructure, due to the expense involved and the critical functions that will depend on it. Open systems hardware and a sound communications infrastructure allow the organisation to operate efficiently and to take advantage of technologies such as e-mail, the internet and document image processing. 69 While many organisations have moved away from mainframe computers, it is important to recognise the valuable role these can still play. Investment in large numbers of PCs should be protected by the adoption of specification standards to ensure compatibility, performance and maximum useful life. Care must be taken to ensure that software provides the functionality required and that appropriate numbers of user licences are available. Financial Information Service Section 3 – ICT Infrastructure Useful Websites Relating to ICT Infrastructure Open systems www.opengroup.org Networking and communications The Electronic Industries Alliance: www.eia.org, and the Internet Engineering Taskforce: www.ieee.org, for cabling standards The International Organization for Standardization: www.iso.ch, for general standards www.yahoo.com/Computers_and_internet/communications_and_networking www.yahoo.com/Computers_and_internet/software/communications_and_net working Vendor sites that provide useful information and white papers Hewlett-Packard: www.hp.com/rnd IBM: www.networking.ibm.com Intel: www.intel.com/network/connectivity/ Cisco Systems: www.cisco.com 3Com: www.3com.com Internet information sites Internet Society: www.isoc.org Internet Engineering Taskforce: www.ietf.org InterNIC: www.internic.net March 2003 Volume 10 – Information and Communications Technology Online periodicals www.infoworld.com www.lanmag.com www.lantimes.com www.theregister.co.uk www.zdnet.com General areas of interest www.brint.com/interest.html Birmingham City Council’s Open Source Academy project Business Link IT and e-commerce page Financial Information Service