Here's a little script that can tell you the producer assigned to a (globally unique) MAC address according to the officially designated allocations. With this you will be able to quantify the number of Apple users who can not follow instructions sufficiently to stop themselves tripping the network trip wire.
If you're googling for "mac address allocations" you really want the "Organizationally Unique Identifier" from here
#!/usr/bin/python import os, pickle, sys OUI_ALLOCATIONS="http://standards.ieee.org/regauth/oui/oui.txt" CACHE_FILE="/home/ianw/.mac2prod.cache" class MACCache: maccache = {} def __init__(self, recache): if (recache): self.setup_cache() return try: f = open(CACHE_FILE, "r") unpickler = pickle.Unpickler(f) self.maccache = unpickler.load() except: self.setup_cache() def setup_cache(self): f = os.popen("wget --quiet -O - " + OUI_ALLOCATIONS) for l in f.readlines(): if l.find("(hex)") > 0: sl = l.split("\t") name = sl[2].strip() mac = sl[0][0:8].replace("-",":") self.maccache[mac] = name of = open(CACHE_FILE, 'w') pickler = pickle.Pickler(of) pickler.dump(self.maccache) def usage(): print "usage: mac2prod [-re-cache] 00:00:00:00:00:00" sys.exit(1) if not len(sys.argv): usage() if (sys.argv[1] == "-re-cache"): recache = True sys.argv.remove(sys.argv[1]) else: recache = False if len(sys.argv[1]) != 17 or len(sys.argv[1].split(":")) != 6 : usage() mc = MACCache(recache) try: print mc.maccache[sys.argv[1][0:8].upper()] except: print "Unknown Producer"