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2. Component hardware £1500 Budget

You have to build a PC shopping list. These prices are hopelessly wrong, but may be an indicator. VAT is UK tax. Any suppliers mentioned, were found in a magazine, and are mentioned for courtesy - as the origin of the information. I have no knowledge of them. NO - I don't sell hardware.

This is an Intel-PC because it is. I don't have an ALPHA or any opinion on them. To be honest, I'm not THAT interested in hardware, which is why Raven is built from standard, replacable components.

As well as the Intel-PC, you will need books. It's your list, don't forget ... hand-scanners, video-frame-grabbers, FM-radio - but check LSM's and Linux DOCs for keywords. Many devices are supported in Linux, but it isn't easy to see HOW-WELL they are supported. Ask your supplier, and other users.

2.1 URLS - Hardware FAQ's

If you have Internet Facilities at work (uni), there are a number of URL's listed in a separate file. If you can't find that file try one of these.

pc-hardware-faq

pc-hardware-faq is a 5 part faq about ibm.pc hardware, BIOS information, etc It applies to Linux and DOS.

Near there is an E-IDE FAQ which tells you about good/bad hardware and the symptoms. It has a list of EIDE manufacturers' URLs.

ftp://rtfm.mit.edu/pub/usenet-by-group/news.answers/pc-hardware-faq/enhanced-IDE/part2

        says PIO-0 is 3.3 MB/s PIO-4 is 16.6 it also lists the IO_PORTS
        for 4 IDE cables (two cards).

        Near there are other URL's about graphics cards and other things.

2.2 BOOK - Linux Doc. Project - LDP (£30)

This book is indispensable. You should really buy it first, as it contains information about hardware.

This is a collection of LDP 'books' and 'HOWTO's, assembled from several sources. Most of the individual authors and editors are now collectively producing the Linux Documentation Project.

The Networking Guide will tell you EXACTLY how TCP/IP and all its various features (NIS, boot servers) are configured. The Ethernet HOWTO hints at what is involved in writing a driver for an ISA card.

The NET-2/NET-3 HOWTO, is the Networking Guide for developers, and provides a well valued second opinion (from the original authors), and different descriptions of the networking software and its configuration.

The Ethernet HOWTO is written by (any maybe for) the writer of many drivers for Ethernet cards. It 'compare-and-contrasts' different card designs, costs and performance. The Hardware HOWTO lists a range of hardware that Linux supports (at time of writing!)

The book is published independently by a number of distributors. More or less the books are the same, from the same text, but may contain different chapters. They are printed at different times and may add extra chapters for their own distribution.

All the information in the book is available on your CDROM or over the NET. http://lsl.com/ If you want to print it and sell it ... please add a better tabbed index.

The online Index of Howto's is available from http://sunsite.unc.edu/~mdw

<-! tilde became amp mbsp in chimera ! ->

2.3 Mini-Tower case: (£30+VAT)

I've just noticed that my mini-tower, puts the back end of a hard disk, where I want my sound card to go! The second choice card slot is also unusable, because the CPU+FAN gets in the way. Oh well.

Of course, if you want an 8 GB server, you will need a big case. You would also need 100-TP ethernet cards to the central HUB.

You may prefer a desktop case, that sits beneath the monitor. Personally I hate these, because they don't work ergonomically for me. They tend to have less space for disks and cards, (or raise the monitor too high).

Conversely, you may hate towers, because they require most things to have an extension cable, which get in the way, and there might be less leg room under the desk. or the floppy is harder to reach.

removable back plane

The back-plane that holds the system board is removable and makes it much easier to set jumpers and handle the PCB. I didn't notice that!

CPU FAN has own PSU cable.

If your PSU has a connector with a pair of thin red and black wires (as well as several thicker 4-wire connectors), make sure that the CPU FAN has the corresponding connector, otherwise you will need a splitter (or plan moving to a box with a different PSU).

2.4 System Board (£100+VAT)

Linefeed is a UK company with opinions, facts and information on a range of system hardware. See www.linefeed.com for their information about ide and system boards such as the GA486AM.

If you get EIDE + Floppy + Serial + parallel on the motherboard, you save a PCI slot. Maybe now that V34 technology is standard it will also appear.

Some boards have faults with extra features, but you should be able to test it fairly soon, and if it is non-standard - take it back. Also any extra features should be disable-able, allowing use of other cards.

2.5 16 Mb memory (£100+VAT)

4 Mb is not enough, 8 is OK, 16 is exactly OK, 32 is rich.

This has come down in price recently from £325 to £100. Shop around. Getting it from the same place as your system board and CPU makes sense. Don't get two lines of 8M, as this prevents you from expanding later, unless you motherboard can take it.

4Mb offered in most 'bundles' is NOT enough (except for a 386/sx running X11 remotely, and local SVGA text apps). 8MB is runnable, but I find it irritating. I'd upgrade, but it's only a second machine, and it's is still a lot of money.

If you can afford a P5 and memory, you are lucky (consider an alpha). If you have to make a choice, go for 16 M memory, with the best 486 you can get.

Without real memory, the CPU spends it time waiting:- re-loading code pages from disk, and reclaiming data pages by writing them to swap, then reading in the required page.

A 'P5-Alive' sticker looks different when illuminated by your disk light.

2.6 CPU: 486-DX2-80

You do not need a Pentium. A 486 runs office apps just fine.

The 486 is yesterdays technology, but it is still meat enough to handle millions of bits in X-window redraws and it multi-tasks smoothly. Running X11 with several windows active, I got a tidal memory usage of 10-14 Mb with low disk activity (less paging). Applications start up and run quickly. I compiled a few system apps (samba, smbfs, smail, ... ) and each only took a few minutes. I compiled the kernel - that took longer.

However, I only use 8 bit X11R6, not 24 bit displays, which uses 3 times as much memory, and has more bytes to move around. I don't watch TV, I don't race MPEG-video-data to disk, I don't mix sound data real-time, and the biggest compilation I do is the Kernel (takes chunk of an hour).

Pentium chips and system boards carry a premium price, and may not be value for money, when competing against other components in a budget. However that depends on what you want to do, office tasks or graphics rendering.

Of course, by the time you read this, costs have changed. The CPU price gap (and motherboard price gap), may make a Pentium worth while.

Software developers - please DON'T get the fastest possible machine. It will only hide the performence problems that others are experiencing when multi-tasking.

DX2-80 means that the memory bus runs at 40 MHz, but the CPU has an internal signal at double that speed: 80 MHz. DX4-100 runs at 25/33 MHz.

40 MHz may push the memory chips to their limit, or require extra wait states, whereas 25 MHz memory is OK. This is set on the motherboard and in the CMOS settings. Problems might show up as occasional system problems, or mysterious lockups. If gcc often gives you SIGSEGV, it may be a memory speed problem, try adjusting your CMOS, or cleaning the contacts.

A Pentium also needs a Pentium system board, which may cost more.

The non-Intel 486's, are close to being 486's (eg the AMD), but the higher clones drift towards their own design, and may require a system board that supports them particularly well.

2.7 EIDE ATAPI disk controller

2.8 multi-function EIDE with IO on-board (£35)

Serial+parallel IO does not need VLB or PCI, it needs 8 bit XT bus! but it does save a card.

If you can get these features on your system board, it saves a card.

2.9 PCI or VESA-Local-Bus ?

Some time ago I got VLB, because it was cheaper and more tested. PCI is now reliable on 486 boards, and you can carry the cards to other machines. It is also faster.

The idea of VLB -or- PCI is to move large amounts of data around, using 32 bit words instead of 16 bits and use better clock speeds doing so. It makes a HUGE difference to the screen and disk drives, but less to the network card, and none to the UART card which uses 8 bit data.

When compiling the kernel, you should select PCI support, and watch out for semi-broken IDE controller chipsets, that the kernel can fixup (but only if you tell it to!)

2.10 DISK drive: ATAPI mode 3 (or more) 1.2Gb (£135+VAT)

There are tiny-Linux installation disks, that let you survive in 10 Mb, but that is the realm of 386/sx printer buffers with NFS disks.

The Slackware base uses 300 MB, a few apps uses up another 300 MB.

If you already have an existing (DOS) system, get a second disk 1.2G for Linux only. Then save up to buy ANOTHER disk! 2.0 G disks are an option.

Whatever you needed, you need that much again! Then you can have two independent systems, ie your existing _old_ system, and your unstable _new_ system.

You could build up the new disk in one of those removable IDE drive bays, then swap it out of the system, as a sort of 1 stop upgrade, but then you will need a second machine with TWO exchangeable bays, to duplicate the 'ROM' you have just created.

If you had the 0.5G DOS disk then the 1.2G Linux, you can use the Linux disk to hold a copy of the DOS partition whilst you repartition the DOS disk, perhaps creating a 32M swap space (performance gain - heads don't move on OTHER disk).

Linux can feed ext2 disks to windows-for-work-groups, but only over the LAN (samba over TCP/IP). Locally Linux can mount DOS disks, but DOS cannot read ext2 partitions (except with a read-only utility and name mangler). OS/2 can read/write ext2 partitions with long names (recent, may be stable).

It is possible for DOS to read individual Linux files using a utility program and a driver that can reach above 1024 cyclinders.

There are variations between disk manufacturers, interfaces, etc. Get the biggest disk with the smallest seek time (access time), and then get PIO-Mode-4.

2.11 ATAPI-EIDE CD-ROM: Quad Speed (600 Kps), 200ms access (£50+VAT)

I have an old dual speed CR-562 on its own interface card, on one system, and an EIDE quad speed Mitsumi on raven. The Mitsumi developed a head-seek fault, but the replacement unit is OK. Other than the hardware failure, I have never had any problems with the quad speed EIDE drive.

The CR-562 uses a Panasonic interface, that appeared on original sound cards, but the EIDE drives use the same EIDE interface as hard disks, so you don't need an extra interface card or driver. It is possible to disable the EIDE-CDROM code in the kernel, but you don't want that.

You might have 3 disks and a CDROM. If the CDROM is on its own IDE cable, jumper it as the IDE master, otherwise jumper it as the slave. Don't use cable select, because even the manufacturers disagree on what that means.

External SCSI CDROM's may require high quality cables and limit the number of drives that can be cascaded (2). This is a generic problem with external SCSI and is often helped by good termination (active).

SIX-speed and EIGHT-speed IDE CDROMS are now available for a few pounds more. After that check seek/access times and reliability.

SEVEN-DISK auto-changers is an interesting idea (especially audio), but there would be a 3 second delay when switching between tasks, accessing different disks. It's only dual speed, and the cost including the SCSI controller would buy a few quad-speed always-online CD-ROMS (in a tower case).

TRIPLE-DISK-IDE auto-changers. I saw an advert for these, but they won't be supported until a driver appears for them.

Don't forget to enable IDE-CDROM in the kernel when you compile it. You know it's there, because when the kernel boots, it lists all drives found, and says "CDROM" against one of them. If the messages ran by too fast, run dmesg.

2.12 CD-writers (£700+VAT)

This is NOT part of the basic Raven spec, but is mentioned here as many people will wish to plan for it.

Writing CDROMS would make it possible to backup and rebuild sections of the hard disk. You will also need a free 660 MB partition to build the filesystem on, before burning the cdrom. This is because cd-writers have to get the data on-time, first-time.

If you plan several installations it offers you a way to duplicate a system, and distribute it to each CD equipped workstation. The writer needs a SCSI card.

If only CD-writers would drop in cost as fast as readers!

2.13 SVGA PCI Cirrus Logic 5434 (£50+VAT+1MB)

2 MB is essential. It allows a large X11 window, with spare space for fonts or BLIT zones.

You might have to purchase the RAM chips separately (£30), but if possible get them on-board (soldered in). Some 64 bit cards may need an initial 4M (+4M blank).

Linux (XFree86) supports many different cards, 5434 is only an example. I'm waiting for a new breed of cards, so I got a CL-5429 VLB. Its fast enough, hi-res, well known, had the spare sockets for the 2nd Mb, it was in the shop, and cheap. It also has on-screen memory streaks.

It's got to be a PCI card (or VLB or on-board) because there are so many pixels in X11, that the ISA bus is *too* slow for snappiness.

The chipset is the core of the SVGA card. You want one with the latest technologies for accelerators and RAM-DAC circuitry, but one that is well known enough to be better supported by XFREE drivers. Look in /var/X11R6/lib/doc for information about supported S3 chips.

I'm not a shop, so you really need to refer elsewhere, maybe: ftp://rtfm.mit.edu/pub/usenet-by-group/news.answers/pc-hardware-faq/video/chipsets

If you are considering a 3-D rendering card, check which are supported by XFree86, (eg Matrox Millenium isn't, though apparently there is a commercial driver for it). (IE for the 3D functions, the SVGA part will be supported).

2.14 SVGA 15" Monitor (£260)

17" IDEK recommended if cash and portability are not a problem.

If you can, get the refresh rate of a range of monitors eg 72 Hz at 1024x768. This gives an indication to the top end limits of the monitor. You will configure the card as close to this limit as it will go (if you want to).

Faster monitors are better, but you also want one with a sharper picture. This will be more apparent at the higher resolutions. Hopefully, the better tubes are put with the faster circuitry, otherwise you should go to the shop and look.

Old 14" monitors should be 'retired' from regular use, but can still be usable with X11 desktops, at 640x480.

2.15 MODEM: V34 28.8k fax/data (£99)

Internal is much neater, but you can't see the lights telling you that something is happening.

Some modems make a lot of noise. VOICE ones have ear phone sockets to listen to line (and otherwise go quiet).

Voice modems can act as ansa-phones, or a MENU of voice directed options, with the caller using a touch tone phone to select options. This might then be a FAX service to a specific user, and both ends switch to FAX mode.

NOTE: Rockwell chips use an undisclosed compression format, so you can play and record sound clips down the phone, but NOT through the sound card or CONVERT them to or from any other format. You will need the software for this to work. I never got voice working (and never leave the machine on when I go out as it is a potential fire risk).

        sunsite: /cdrom/system/Serial/mgetty+sendfax-0.98.lsm

I've seen a V34 + SoundBlaster combo advertised. Hope it works.

US models detects most BT signals sort-of badly and are 2/3 the price. BT approved models are no better, but sport that stylish green triangle. If anyone can tell me of a modem that CORRECTLY detects all UK signals, please tell me. Mine has to timeout.

Personally, I distrust RS232 WIRES at high speed. An internal modem doesn't have an RS232 cable, it has a virtual wire, the length of a chip, and is less prone to noise. SLIP and PPP will detect any errors, but why get them at all?

Individual brands may have special bugs, or capabilities, such as CallerId (know the callers phone number before answering). You milage may vary, see mgetty.

My Internal V34 modem (an early version) had unbelievable problems with IRQ's when it was set to anything other than COM3 (the default additional COM port). This may have been it's fault, or the fault of the IDE card not getting out of the way. Things got a lot better when I put them both back on their preferred "default" settings.

2.16 PRINTER: none, Epson-FX80, or YOUR-CHOICE (NON-GDI)

Linux will drive a POSTSCRIPT printer or any "common" printer. HP, Epson, 24-bit dot matrix, color-ink-jet, PCL, etc. You can get a second hand 9-pin for £20, but they are slow and noisy.

I don't know anything about laser memory requirements, for complex pages. Especially since ghostscript will be converting to a pixel image.

GDI requires MS-Windows software to drive it. I don't think Linux does this yet. But some GDI printers have an 'upgrade to normal printer add-in'. and can be driven in PCL from DOS.

Printer cables can be quite long, but beware of total length, with switch-boxes. The printer will go quiet if the total footage is excessive (40 ft). If you are lucky, you can avoid buying an expensive, bulky and messy printer, and use the printer at College, or work.

2.17 TAPE-DRIVE:

Don't bother. Get a second disk, and keep YOUR files on floppies. Label the floppies 9601-Jan, and keep backups of them on an ext2 disk. Take TAPE backups of that ext2 disk.

The system is HUGE, but can be deleted and re-loaded from CD-ROM (as you shall see ...). Reloading the system from scratch is difficult to get right without forgetting SOMETHING, but each time, make a note to improve next times installation procedure.

Collect all the ftp files you found. Put the ones you have installed on a backup archive. If the machine needs to be rebuilt, you have them.

For site backups use an external CD-writer. This won't backup working PC's, but you prepare a 660M image using mkisofs, and borrow the CD-Writer for an hour (or so). Sites with incremental backups merge departments, each 'posts' 50M to a weekly backup (N-copies takes N-hour's :-). How do you dispose of CD's?

Some tape drives are very noisy, and can't be active in the same room as a human being. DAT tapes (quiet) have a high capacity, but cost a lot.

2.18 Removable media

I have an old Syquest SCSI 80 MB cartridge, which works very well. There are newer 1 Gig drives, and these should work well, (using standard SCSI interfaces).

I did have problems with DOS requiring a reboot on every change, but this is NOT a problem with Linux.

They are more expensive than faster non-exchangable disks, but may be more suitable for sending through the post to get CDROM's cut, or more convenient for archives, or moving between machines.

The parallel interfaces, will be much slower than internal SCSI cards, and you should check whether they are supported or not, and the convenience looks very tempting. It is, however, another box, power cable and interface cable. Portable users would probably swear by them.

If you don't want to switch disks very often, you might consider an exchangable SCSI or EIDE frame.

2.19 Sound Card (£35+)

I don't have one, though I have seen one at £20 (second hand). I did have one a long time ago, but I was disappointed by the amount of HISS and general sound quality. I lent it to a friend, who has moved.

2.20 Multi-disk system upgrades

System upgrades are easier if you can boot two independent systems (as well as DOS). IE: the old-system and the new-system. If you plan to do that you must reserve the disk now, possibly leaving you with only 2 of 4 disks (+new system, +cdrom)

During the migration, you might do a lot of deleting. Be lucky.

If you are lucky, you can share /usr/andrew, eg as /hdc2/andrew. With other apps, beware of different library file versions, but try /etc/ld.so.conf.

2.21 Second disk (£135)

Put the second IDE on either the first or second EIDE cable and controller.

With both disks on the same cable, one must wait whilst the other uses the IDE cable. You will need a second ide cable (the first one is always included with the controller card), and scrounge a few jumpers. Check that you have enough PSU cables (or a splitter).

DOS currently halves the data path width of a hard drive ON THE SAME CONTROLLER as the IDE CD. Linux does not have this problem. It may be fixed with a DOS driver.

Splitting data across two disks can boost performance, for a number of reasons. If you are hardly using the DOS partition, but have a swap space on that disk, every time the system wishes to read or write a swap-page (4K block), it can do so without moving the disk head of the other disk, and conversely.

2.22 Bundled Machines

Shops often put out adverts of complete machines at low prices. These are not fakes, but checking the specification, you may notice only 8Mb RAM, or whatever. Take the specification home and price it on an item-by-item basis. Then go back to the shop with a proposal for an upgraded machine, they'll probably snatch it out of your hand. Remember that their prices depend on sustained turnover, and your thousand will enable them to get newer stock.

2.23 Books

Running Linux - Matt Walsh

Subject to availability.

Essential System Administration - Aileen Frisch

I don't have this, but I've heard it is very good.

Linux Documentation Project LDP

Did you know that in the UK, books without CDROM's are VAT excempt (17.5%). This book may appear under different names, eg:

Doctor Linux - LDP selection printed (£30)

This book is indispensable. See above. I've seen this advertised for $22, but then you need US-UK postage. It weight 4 pounds, so confuse your local post office with two bags of sugar. US-UK air mail can take 2 weeks, bulk mail ... who knows?

TCL/TK John Ousterhout (£29)

TCL is a threaded interpreted language that is a sort of a mix between BASIC, LISP and SHELL. Its very flexible, but has a limited number of data-types (as does shell).

You can add C++ code into Tcl, or add run_tcl_script() ability to you program. ELF will hopefully add dynamic linkage.

TK is a library that bolts onto Tcl and X11, giving object types such as frame, label, button, radio-button(s), data-field entry, canvas, text_panel_widget (with multiple fonts, etc, etc).

Tcl/Tk is rumoured to run on WIN-311. When that hits the fan, a lot of windows programmers will go lemon squeezy. I don't know what DOS does for unix services, but it sounds like a reasonable cross-platform tool.

This book is the authors guided tour of features. It is a reference for commonly used command options, with an accurate and concise index.

Others

If you have a book you'd like reviewed, email me and I'll have a look.

Linux Journal ($22 US, $32 world)

A monthly magazine, with lots of articles. Its has technical articles, background info on famous names, development progress stories (Is BLADE running yet?), and a very high quality finish. It's nearest sibling is WebMaster, also from www.ssc.com.

Linux Gazette

This is a FREE online e-zine, available as html and available for download. It also appears on some CDROM's.

2.24 Motif - optional

X11 is a window maker's toolkit. Different window makers experimented with different styles. EG:

        TRAD. Scroll Bar Behavior: CLICK-ing on SCROLL-BAR:

                LEFT    - scroll page up so that THIS line is at top
                RIGHT   - UNDO of LEFT
                MID     - JUMP to this % place in DOCUMENT
           DRAG-MID     - scroll text (tiring)

        OTHER Scroll Bar Behavior: CLICK-ing on SCROLL-BAR:

                LEFT    - scroll page up by one page
                LEFT    - scroll page down by one page (above bubble)
           DRAG-LEFT    - scroll text (tiring)

Each of these, and the variety of them are confusing to people who are used to MS-WIN, and everyone got excited about the Motif library (and style guide). In the need to declare a standard, they did so.

X11 is FREE, with contributions from the big names. Motif costs, so you have to buy it separately.

Then you can down-load all those Motif applications, compile them, and link them with shared-libraries. The rest of us can't compile them, and can't link them, so we down-load the bigger static-library executables.

A Motif clone is brewing (LessTif). It will take time for everyone to confirm that their code compiles and runs correctly with it. In the mean time you don't NEED it (Motif). Most of the interesting stuff compiles without it. The rest is available pre-compiled from the net .

Motif is not fast. I only realised that the motif linked executables were sluggish when I saw faster ones. Utilities (xedit, xterm), applications (modula-2:oberon), or even scripted applications (using tcl+tk) - so comparatively fast it is astonishing (and depressing when its back to sludge).

FYI I find ddd slow. Is this Motif, or my machine?

In balence, the Scriptum program is static Motif, and is fast, so maybe it isn't just Motif that causes the problem. However, I prefer to have everything on one CDROM (set), so I'm waiting for LessTiff, and prefer not to code X11 directly (using Tk or other instead).

X11 includes a set of applications that do not use Motif, and a proportion of the software on sunsite (etc) also.

2.25 Internet Service Provider - account - (£10+VAT pcm)

There are different types of dial-in accounts. You want your own static IP address with full TCP/IP access to the Internet.

You also want some space on the ISP's machine for your web pages, available 24 hours. You may prefer an ISP that has a fixed rate, no time charges, and ask about 0345 (local call) options (£15 pcm).

An ISP has a "high speed" 24 hour link to a gateway near a backbone. The ISP also has 1-500 modems, each with its own phone line. The 500 connections fan-out with 4-16 modems per terminal server.

Your ISP provides you with a gateway for routing packets to/from the Internet.

The ISP has one machine that checks your password when you dial-in, and permits access to the services (SLIP) you pay for - routing packets from your host to and from the Internet.

The ISP has other machines to provides you with services that ISP's are supposed to provide, ie:

Remember that most people are still MS-DOS based, and your ISP's support desk might not have a lot of Linux experience, but when you are connected, and after you have read the FAQ's, there are a lot of people who may recognise your problem.

2.26 T-H-R-E-E Button Mouse (£7.50)

My very old serial logitech mouse recently got trodden on, and I looked at several on display for £30, and didn't like any of them. Then I resigned myself to the cheapest I could find without even looking at it. You decide whether you want an Taiwanese mouse in the current political climate.

It is a Genius Easy Mouse, and it is brilliant!

It is a serial mouse, so set /dev/mouse -> /dev/ttyS0, and it is configured as Protocol "MouseSystems" in /etc/XF86Config and in /etc/rc.d.rc.serial it is gpm -t msc.

2.27 MISC

2.28 MISC-II if you have a second 386/sx, MORE, or LESS

See the ETHERNET HOWTO for more information about cards. An ISA NE2000 clone, is fast enough to run the wire at full speed, but it probably has a high 'cost' on CPU overhead, hence is 'slower'.

I used jumpered IO_ADDR + IRQ, so that I don't have to run a DOS utility to program the card.

2.29 Home Ethernet Cables

If you are building a new network in a tiny office, install the absolute minimum that you can relocate easily. IE loose 10-MB thin ethernet.

They're the cables with 'T' pieces. You string the PC's in a line with a terminator resistor plug on the end 'T' pieces. Unconnected PC's are simply unconnected. The cable is like TV arial coax.

The PC's are strung in a line.

        X-T-----T-----T-----T-X
          PC    PC          PC

2.30 Office House Cables

TP is twisted pair high-grade phone wire that runs 100-M ethernet -or- 10-M. Every wall socket cable runs to where the HUB is, with a spray of cables sprouting out of the wall. Each tagged wire has another 2 metres and an end plug (you need a crimping tool and box of plugs).

7 cables plug into the HUB box (£200) which has a mains plug. That gives you 7 PC's on a private LAN. IE the entire building. 15 port HUBS are also available.

Specify 100-M TP cables, even if you only use standard 10-M TP cards. Burying TP cabling with a BT staple gun is expensive but easy. Digging it up ...

2.31 Office Floor Cables

If you have 100 PC's on 3 floors, every wall socket is labelled, and runs to the rack cupboard in the room adjacent to the dry riser.

Each work group has their own HUB.

Groups that have PC's with mixed 100-M and 10-M cards will need a pair of HUBS, and a host to bridge them (or indirect connections via other work groups).

The group's server is located with the group, and like all their PC's, it has a TP cable to the local groups HUB.

The group's server also has a second (hi-speed) card, and it's TP wall socket, runs to where the HUBS are, then plugs into an extension cable that runs down the dry riser, to the computer room, where it joins a HUB of other groups' servers.

The group server is acting as a gatway/router, as well as providing it's services to the LAN-HUB and to the BUILDING-HUB.

Any of the group's servers can be the gateway, it just needs 2 ethernet cards of the correct types for the cables. If you chain LANS of 15 hosts with gateways between HUBS, you will want to monitor traffic levels.

For example, here are two groups connecting to the central LAN.


         HUB                      HUB                         HUB
         |||                      |||                         |||
         ||+-GW-------------------+|+-------------- -------GW-+||
         ||                        |                           ||
         |+- PC                   |||                      PC -+|
         |                                                      |
         +-- PC                 RHUBLAN                    PC --+

You may need to consult a cabling and networking company to get this done. If you do it yourself you will only have yourself to blame. But at least you can start asking questions.


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