Sure it is, just make sure you are being thoughtful of the function you are there to do for your current employer. Fulfill your responsibilities there first, but keep a watchful eye out for opportunities to network for yourself!
Tech conference are sometimes attended by a couple of recruiters, but mostly technical employees make up the attendee list. If the attendee directory is available ahead of time and you know you'd like to do some job networking, see if a target company is sending any recruiters and reach out to them. If there aren't any, pick a few companies that interest you, find a couple of folks attending from those companies, and proactively reach out to them, letting them know it would be really nice to meet them at the event.
Otherwise, you can peruse the booths and have meaningful conversations with representatives - noting that "this is a very interesting product! I'll bet it's really fun to work on the team that is creating this new feature/release/etc." Take business cards, write a note to remind you of the context of your conversation, and send an email after you return home from the event to let them know of your interest in employment there.
First and foremost, however, be respectful of your current employer's purpose for having you there. There's no reason you can't test the waters for yourself during your free time!