I havenīt read the whole thread yet so I donīt know if anyone has mentioned these options.
Benjammin has a good idea - the flame. I have been thinking of getting some kind of torch or even creating it myself as a self defense weapon against the attacking animals for some time. This torch should be lightweight, it should have a good range but it should not be too big.
You could attach it for example to the side of your back pack. It should be attached the way that you could "draw" it easily and very quickly. Then you could train yourself to the sequence of the moves - pull it and then light it using lighter/whatever as fast as possible.
You could keep the dogs/other animals away by waving it etc.. I think they should instinctively fear the fire even if they would not touch the flame directly.
The key feature of the torch would be that the torch cannot put out no matter how wildly you are waving it.
Maybe you could handle several dogs with it if you would be very fast, centered and therefore could detect and prevent an attack from every direction. You could then retreat and find quickly some place to go where the dogs cannot reach you (if they would still be around you) - tree, building, ... and then call for help.
At least this is my theory. And itīs unproven theory I just thought might work.
For example
this torch looks quite good.
Another torch. Do you know other commercial camping torches?
The other solution I have been thinking about would be some kind of sonic weapon.
This
ultrasonic Dog Repeller looks interesting but from the description it is not 100% solution.
A promising description of the
Sonic Devastator.
(Excuse my English.)