You can play on a lan network.
STEP I
DOWNLOAD ARMA II AND THE TWO EXPANSIONS http://thepiratebay.se/torrent/7310976/Arma_II_CO___OA_1.60_-_DayzMod_Online_100__[Joe_Smith-BR]
STEP II
PATCH IT http://www.arma2.com/index.php?Itemid=20&option=com_rokdownloads&view=folder&lang=en
STEP III
DOWNLOAD THIS http://alt.tunngle.net/redirect/redirect.php?to=http%3A%2F%2Fwww.arma2.com%2Fbeta-patch.php
AND PATCH IT
STEP IV
DOWNLOAD DAYZ MOD http://www.dayzmod.com/downloads.php
MAKE A FOLDER IN ARMA 2 directory then name it @DayZ. Make a folder in @Dayz name it addons. Add the files from the mod in there.
STEP V
DOWNLOAD TUUNGLE http://www.tunngle.net/index.php?l=en&pg=downloads
REGISTER AN ACCOUNT
STEP VI
USE KEY CHANGER TO CHANGE CD KEY OF ARMA OA
THERE IS A KEYGEN IN THE #JIMBO FOLDER IN ARMA 2 DIRECTORY
http://www.mediafire.com/?yqeyuzdmpeiys5m
USE TO CHANGE THE CD KEY
WHEN USING KEYGEN MAKE SURE TO SELECT CORRECT EXPANSION
STEP VII
USE THE BETA ARMA II SHORCUT. TO START IT.
TO PLAY DAY Z YOU WANNA START TUNNGLE FIRST
-LOG IN
-JOIN ARMA II DAY Z NETWORK SHOOTERS-> ARMA II DAY Z.
-START ARMA II OA BETA SHORTCUT
-GO TO MULTIPLAYER CLICK ON BOTTOM LEFT TO CHANGE TO LAN.
THE THREE BEST SERVERS ON ARMA II DAY Z LAN ARE THE ONES WITH DE AND PL IN IT. Those three severs save character between each other and they're more populated and on 24/7
IF THESE DIRECTIONS ARE TOO COMPLICATED THE TUNNGLE CLIENT HAS A "DON'T PANIC" BUTTON THAT TELLS YOU THE EXACT STEPS.