We use N1MM contesting software which can be networked. It keeps a running score and also has a dedicated chat server built in. N1MM is free, works great and can really help boost your score if used in the correct way.
In a portable multi-station environment, you can set your stations up a couple of different ways. The first is to have dedicated stations on each band and they never deviate from that band. In this setup your logging computer doesn't really need to be aware of who you worked on other bands, so you don't have to worry about dupes, but your blind on what others stations are doing. If you are on 20m and you just worked a station you might need on 40m, how would you know? If you did need that station on 40m, what frequency would you point him to? Is the operator in your group running on 40m, or searching and pouncing? Running in "island mode", you don't know who's logging what on the other bands.
The second options is to have multiple operators spread out doing their own thing on different bands with some loose operating rules with networked computers. In the N1MM networking window, I know exactly who's on what band, if they are running or S&P and what frequency they are on. If I need to pass a call to someone on another band, I can put it up in the chat which then gets broadcast to all stations. This makes it easy to get those multipliers on different bands. In this environment, you are aware of who's on what bands and who those operators are.
All the portable operations I've been a part of have been the latter. If 15m is hot and you have an antenna that can run 15m, start running on 15m!! If 20m is dead, change to a different band based on what others are working. There really isn't a lot of rules, and it's up to the operators to make sure they are not stepping on other bands but still making lots of contacts. It's easy to keep track of who's operating where, so if someone steps away, we can communicate that and someone else can pick up the band where they left off.
Since we choose to network N1MM, that means building out a large WiFi network depending on how spread out we are in our portable setup. Running an off the shelf WiFi router you get at Best Buy just doesn't cut it when trying to shoot long distances, so I Frankenstein-ed my own WiFi solution that is self contained and waterproof with options of extending the signal to another external WiFi antenna.
I did use an old router that I've had lying around, but flashed DD-WRT firmware on it, which basically turns it into a super router with much more configuration settings. We can boost the WiFi power coming out of the router and turn off antenna diversity to push all the power to 1 antenna. In order to make the most out of the space within the enclosure, I stripped the wireless router down to just the circuit board and installed on a mesh insert with double sided velcro. It connects to an 8db gain omni-directional antenna attached to the side of the box.
The box and mesh insert can be purchased on Amazon.
The bottom is (will) be filled with waterproof cable glands. Four of them to be exact. Two that will connect the R and L antenna ports. One for an Ethernet cable to connect another remote WiFi extender that we will connect with a 100ft cable and another cable gland to bring power into the box.
In the picture above, the power cable gland has yet to be drilled. The power will come from a 50ft extension cable, where I will cut off the plug end, feed it through the gland and then re-attach the plug end for the WiFi transformer. There is a torrid to help keep RF out of the board from the transformer. The power will route along the side of the box, keeping it as far away from the transmitting antenna cable as possible.
The antenna is an 8db omni-directional antenna that has a holder bolted into the side of the box. A little hot glue made the connections waterproof. The antenna sticks up around 8 inches above the top of the box.
The whole box will be attached to a painters pole with some U brackets and mounted to the side of the RV or sign post in the middle of camp. I'm hoping that we can get 300+ feet range out of the antenna, as that's about as far away operators will be with their laptops. Even if we don't get a huge amount of bandwidth, that will be ok, as N1MM doesn't take that much data. Plus if we sync our computers often, there shouldn't be any issue missing contacts.