Adding to the network

January 5, 2005 12:54 PM

An office has a single network drop which winds through the walls back to a switchbox in the server room. This office holds two occupants, both of whom would like access to the network. How would the occupants go about sharing this network drop? A "splitter" (is there such a thing?)? A router? Should one machine sharing the connection with the other? (Is more information needed?)
posted by jdroth to Computers & Internet (10 answers total)

Best answer: You want a switch. People also call 'em hubs, but the term hub technically refers to an older, less complicated device. They're cheap.
posted by zsazsa at 1:00 PM on January 5, 2005

Assuming there is no device on the network enforcing a policy of a single machine per drop (for instance, a switch which does MAC address filtering or a DHCP server which will only hand out one address per drop), just connect a cheap 4-port Ethernet switch and the two machines in the office (connect the drop to the switch's uplink port, and the two machines to two of the standard ports).

If there is a device enforcing a policy of a single machine per drop, and you must circumvent the policy due for some bureaucratic reason, connect one of the combination home gateway/routers/switches to drop and your two office machines to the gateway. Make sure you enable NAT on the gateway.
posted by RichardP at 1:04 PM on January 5, 2005

You can get cheap a little box that will do DHCP, NAT, and provide WiFi that pretty much just plugs in and works. I've had pretty good success with Linksys but everyone has opinions on brand...
posted by freebird at 1:24 PM on January 5, 2005

If you're talking about two people sharing a single ethernet cable then this is what you want. You need one at either end (natch).
posted by dodgygeezer at 1:47 PM on January 5, 2005

Seconding zsazsa and RichardP, you want a switch — it's unlikely that the network enforces 1 IP per drop — and probably a couple extra ethernet cables.
posted by revgeorge at 1:50 PM on January 5, 2005

If the switch you want to buy has no uplink port, you'll also need a crossover cable to connect from the switch to the network point.
posted by seanyboy at 2:16 PM on January 5, 2005

Don't worry about the crossover cables - any switch that supports Auto-MDIX doesn't need them.

The first switch on zsazsa's "They're cheap" link ($11.49) supports Auto-MDIX.

That and two standard ethernet cables is all you'll need.
posted by cactus at 2:45 PM on January 5, 2005

Seanyboy: in my limited experience almost all modern switches/routers auto-detect the need for crossover and adjust accordingly (called Auto-MDIX - and on preview I see cactus beat me).

jdroth: broadly speaking, and someone pedantic is free to leap in here and beat me about the head . . .

Hub: a simple repeating device. What gets transmitted into one port gets sent to all the others - endpoint devices (your network card) are expected to do their own filtering for the signals intended for them (they don't have to and sometimes passwords are intercepted via this method, but that's a tangent . . .)

Switch: Like a hub, but properly directs traffic from the proper source port to the proper destination port. Helps with congestion under heavy traffic load and all that. Most modern 'hubs' are really switches these days.

Router: a general-purpose device with some form of programmability as regards how traffic flowing through it is 'routed.'

What you want is a simple 4-port switch for like $40/50 at CompUSA or probably cheaper at the local whitebox store.
posted by Ryvar at 2:47 PM on January 5, 2005

Note that cat5 splitters are evil little things that break standards and may not work if the cabling is of poor quality. That said, a place I used to work had heaps of them and I recommend them for your situation over a hub.
posted by krisjohn at 7:04 PM on January 5, 2005

Response by poster: Thanks for all of the advice. I bought an eight-dollar switch at Fry's. With the existing cabling, all seems well. (And by this I mean that both machines can access the internet. I'll know more about LAN-specific stuff tonight; one's a Win98 machine, and may cause me woe.)
posted by jdroth at 7:24 AM on January 6, 2005