Thanks. I am going to look into which container would best fit my requirements. I haven't yet got a unique identifier for each record (local port number?), but I could always implement one, and use a map, as someone suggested. If I don't use a unique ID then I could use a list as jlou suggested, to minimize the cost of erasing elements.

Thanks for the suggestions. If I mis-interpreted someone, sorry. I'm going to have a good read through your suggestions as soon as I get some time to read them thoroughly.

Dan