Authorised users are serving members of the Regular and Territorial Army, Reservists and their family members and guests. Access from non British Army personnel must be as a sponsored guest of a serving soldier.
3. Unauthorised attempts to access ArmyNET are strictly prohibited and are an offence under the Computer Misuse Act (1990).
4. The use of departmental Communications and Information Systems (CIS) facilities is subject to monitoring. Material held on MOD CIS equipment is considered to be the property of the MOD. Any information held on any MOD system may be made accessible to the chain of command or investigators without prior recourse.
Unless it's changed (I haven't been on there for ages) anyone can go on there, as long as they are sponsored by a member of ArmyNET. Why on earth they would want to though is beyond me, they (MOD Civilian type person) would have the Intranet anyway wouldn't they? I don't think there's any more information on ArmyNET than there is on Defence Net for civvies, is there?