WLAN as an alternative to leased line.

1. WLAN as an alternative to leased line. Stewart Sharpe.

2. Cisco Systems. 3Com. BreezeCOM. Culubris. Lucent. Enterasys. SpectraLink. Intersil. Vendor neutral supplier. Mobius Technologies Ltd. can supply solutions from a huge range of vendors on an impartial basis. These include: -

3. Basis for choice of solution. • Reliability. • Application suitability including security. • Expandability. • Upgradeability and investment protection. • Customer support. • Cost effectiveness.

4. Solutions to be highlighted. Cisco Systems – Aironet. 3Com – Airconnect.

5. 2 different applications to be studied. • Huge number of scenarios available to us for each solution. • We have chosen straightforward scenarios for demonstration. • Case studies later, will expand up on this basic representation.

6. 2 different applications to be studied. Cisco Systems – Aironet. • Point-to-point/multipoint link between buildings. • Applications with specific or extended coverage requirements. 3Com – Airconnect. • Office environment LAN.

7. Scenario 1. Multi-building LAN extension.

8. Scenario 1. 1. Main office building. Centralised location of: - • File servers. • Mail server. • Internet connection.

9. Scenario 1. 2. Sub-office within the main campus. • Office uses all facilities of main office. • 15 network users.

10. Scenario 1. 3. Sub-office within main campus. • Office uses all facilities of main office. • 30 network users.

11. Scenario 1. 4. Sub-office outside main campus. • Office uses all facilities of main office. • 15 network users. • Public road between office and main campus.

12. Scenario 1.

13. Options for extending network. Campus buildings 1, 2 & 3.

14. Options for extending network. Campus buildings 1, 2 & 3. • Wire between buildings. • Fibre between buildings. • Wireless bridge between buildings.

15. Characteristics of options.Wire/fibre between buildings 1, 2 & 3. Benefits. • Limitless bandwidth possibilities. • Permanent link with little maintenance. • One off installation costs.

16. Characteristics of options.Wire/fibre between buildings 1, 2 & 3. Drawbacks. • Typically would be buried in ground. • Huge upheaval to existing features e.g. car parks, footpaths, landscaping etc. • Time consuming and costly installation. • No benefit in relocation.

17. Options for extending network. Buildings 1 & 4.

18. Options for extending network. Buildings 1 & 4. • Dial-up connection between buildings. • Leased line between buildings. • Wireless bridge between buildings.

19. Characteristics of options.Dial-up connection. Benefits. • Easy quick installation using existing lines. • Adequate for occasional usage. e.g. Weekly submission or update of files. • Can be used in multiples to increase bandwidth. • No office relocation issues.

20. Characteristics of options.Dial-up connection. Drawbacks. • Very slow for all but most basic tasks. • Multiple connections increase unit costs. • Inconvenience of repeated reconnection. • High relative costs.

21. Characteristics of options.Leased line. Benefits. • Permanent link. • Huge bandwidth availability. • Reliable connection.

22. Characteristics of options.Leased line. Drawbacks. • Not always possible to install. • Expensive installation costs. • High periodic costs for higher bandwidth. • Long lead times for installation. • Relocation requires re-installation.

23. Characteristics of options.Wireless bridge. Benefits. • Very quick and simple installation. • No periodic charges. • 11Mbps bandwidth. • Permanent link. • Easily relocated.

24. Characteristics of options.Wireless bridge. Drawbacks. • Requires clear line of sight between points. • Bandwidth diminishes as distance increases. • Site survey necessary as a pre-requisite.

25. Site survey. Necessary to ensure the following: - • That no unforeseen circumstances render system unsuitable - prior to purchase. • Highlight precisely what will be available. • Accurately specify equipment required for quotation purposes. • A clear picture of physical layout in advance.

26. Costings.Scenario 1. Suggested. • Point-to-multipoint link between 1 & 2, 1 & 4. • Point-to-point link between 1 & 3.

27. Costings.Scenario 1. • Allows 11Mbps to be shared between the 1 - 2 link and the 1 - 4 link. • Allows a full, separate 11Mbps link between 1 & 3.

28. Costings.Scenario 1. Site survey. • 2 people on-site for 2 days. Point-to-multi-point link. • Bridge and omni antenna for building 1, bridge and yagi antenna for each of building 2 & 4. Point-to-point link. • Bridge and yagi antenna for buildings 1 and 4.

29. Costings.Scenario 1. Installation. • 2 people, 5 days. Additional equipment. • Lightning arrestor per location. • Antenna mounts and connectors.

30. Costings.Scenario 1. Additional costs (unknown.). • NEMA enclosure per location. • Electrical contractor to provide supplies to enclosures and earth lightning arrestors. • Any masts required to gain line-of-sight.

31. Summary of benefits. • Bandwidth adequate for most applications. • No periodic costs. • Quick and easy installation. • Short lead times. • Ideal in difficult situations. • Easily relocated with the business. • No license required.