Meeting: Demystifying Networking

Report by Peter Richmond and Chris Hughes

Last month’s meeting covered the topic of networking RISC OS computers, both with themselves and with other computers as well as with network storage devices. It was ably handled by Steve Potts, Chris Hughes and Steve Fryatt, using a number of machines. Indeed there was also going to be Steve Bass as well, but he forgot that he was on holiday!

The evening started with the usual announcements, including another appeal for a meeting coordinator – so far with no response. It’s time that someone else stepped forward, as Chris has now stood down from the role. There was also an appeal for people to write meeting reports for the newsletter and website, although this too has met with a limited response. We know people find these summaries useful, but it is always the same people writing them.

The first thing to cover was why we would want to connect two or more computers together – generally, it’s a more convenient way of transferring information between the two. Of course you could use floppies, Zip drives CDs or USB memory sticks, and for computers that can’t have a network card fitted, that’s what you might have to do.

Machines that have RO 3.7 or later can have network cards, and some of these are available second-hand from the usual RISC OS sources; older machines can usually take network podules, which again are available second hand. Iyonix and RiscStations already have network cards built in, and Omegas could have one fitted (mine’s got one).

Joining the wires

The simplest way of networking is to use two RISC OS machines with a cross-over cable. This is usually called a Cat 5 crossover lead. With the correct setting up, this allows each machine to see the other’s hard drive.

If you’re trying to connect to other computers, you’ll need to do two things – buy a network switch, and use a different method of talking to the other computers. A network switch is like a splitter and connector for computing devices, and can have a wireless feature within it, so you can use a laptop to talk to a desktop and all of the computers could talk to one or more printers – much like a small business might use.

Connecting machines that are in different rooms can require a lot of network cable, so there are some alternatives. ‘HomePlug’ networks using standard mains wiring to transmit the signals between two power sockets, linking two or more pieces of a Cat 5 network together. Chris had brought a couple of HomePlug adaptors with him, and explained some of the options. There was then a live demonstration of the system, with Steve Potts on the far side of the room using VNC to control one of the three computers at the front by way of the sports club’s power sockets.

Finally, as far as the hardware went, Chris had brought a couple of print servers with him, which allow standard USB or parallel printers to be connected across the network. He told us that similar hardware was built in to many modern printers, allowing them to be connected to several machines at the same time.

Software issues

The next part of the evening was Steve Potts explaining a bit of the technical stuff behind networks with the aid of a slide show. He started by explaining IP addresses, before looking at net masks, the difference between ‘255.255.255.0’, ‘255.255.0.0’ and so on, and what effect this had on the IP addresses like 192.168.0.1 and 10.1.0.10.

Chris returned to take a look at using Access shares (ShareFS) between RISC OS computers and even Virtual machines, and demonstrated rather effectively just how confused you become with all the hard drives being called ‘HardDisc4’ – it can even confuse Access. We then saw how an alias name can be used to help work out which computer you are looking at.

You have to decide whether the disc in each machine can be only read from, or can be written to, across the network – this is done by the Share options in the hard disc menu. You can limit writing to only one folder. This scenario would probably be of more use when there are computers outside of your own network – for example letting someone over the internet access one of your folders. It’s worth noting, if you’re always using one computer as the master, that once you’ve set up your computers you don’t need the remote computer’s monitor on.

The final part of the evening was taken by Steve Fryatt, who showed how to link different systems like RISC OS, Linux and Windows so that files could be shared between them. He used a variety of software, including Sunfish and Moonfish, SambaServer and LanMan98.