Cellular Mobile phones

I was recently offered a "free" Cellphone with a product I bought. While I accept that it may be a condition of accepting the "free" phone that you also subscribe to their airtime, is it actually illegal not to purchase an agreement with the phone?

When you buy a phone from Dixons, say, rather than from a dealer (who gets a golden hello of 100 quid + from the air time provider) you don't have to sign up with anyone. All you get is a info pack for Call Connections (with Cellnet). The phone in this case is pre-registered with Cellnet, but that shouldn't prevent you from signing up with Vodafone.

However, in your case, the supplier of your "free" phone is expecting a nice big kick-back when you sign up, and is unlikely to give you the phone without an airtime agreement. Usually this type of disreputable dealer will rip you off for rental and call charges, to recover the subsidy of the "free" phone. When the dealer says its illegal, what he really means is that its unprofitable for him!

Also, beware of gotchas such as the following

Will calls from PSTN lines to mobile phones, in other countries, work? What premium will I pay above the normal charges?

Yes it will work. It costs the same as phoning a normal number in that country. One daft thing about the current charges is that it can cost less to phone a Eircell mobile phone in the Irish Republic from the UK than it costs to phone the car parked outside your window (if you would want to!).

Will inbound access to UK mobiles work?

You can call any UK mobile phone from overseas.

Where can I get details of Cellnet, Vodafone, One2One and Orange coverage?

One of the two mobile phone magazines available ("What Cellular Phone"?) has coverage maps for Vodafone TACS, Vodafone GSM, Cellnet TACS and One2One in the back pages. You can also get Carphone Warehouse's (0800 424 800) colour catalogue, which includes the maps.

Orange have info on 0800 286 286. There are some coverage maps made available for Orange at <URL:http://info.mcc.ac.uk/MCC/OtherPages/Orange/>.

Why do analogue cellphones have a 'soft' serial number, enabling alteration?

It is a problem with the cellphone manufacturers, NOT the TACS/ETACS specification which states that the ESN should be hard coded within the phone. However this causes huge problems when the phone goes for servicing or gets broken etc. so many put the ESN in EPROM, EEROM, PROM etc. therefore cloning becomes very easy.

With GSM or PCN (which is based upon the GSM spec, but at a higher frequency) the ESN's are stored in a different way. You also have two 'ESN' per phone, one for the phone itself and one for the SmartCard with the user details. Both have to be validated.

Interestingly, authentication of a mobile subscriber for use in a TACS network is available. The method that is defined in Issue 4 of the TACS specification has been implemented my all the major vendors of mobile equipment.

The network side of the implementation is already in place in the UK, Italy, China and the UAE. The system is cheap to introduce into the mobile phone and is also very secure. But operators like Vodafone and Cellnet have not promoted the use of TACS authentication.

What do Cellnet Callback and Vodafone Messenger offer? Who do I ring for help?

Both offer storage of messages whilst your phone is switched off or unavailable (eg the network is busy or you don't have a signal), in fact the voicemail software is written by the same company.

For Messenger help, ring the Messenger help line on 0836 823823. They will set up an account with a PIN so that only you can access your messages. They'll also tell you how to set up the divert etc.

To activate the Messenger's recall box, dial 121 and ask the operator to activate the facility. However, if you do not use the recall service for more than 30 days, then you will have to re-call 121 and ask them to switch it back on again.

What prompts the Cellnet callback or Vodafone Messenger systems to call back?

1. The network was busy when there was an incoming call, but it now has spare capacity, or the switch/ cell site you were using had no capacity to pass the call.

2. You were in a no service area, but now you are available again.

Each cellphone is required to register itself when it is turned on, or has moved into an area of coverage from no coverage. They also reregister every now and again just to ensure the network hasn't forgotten about them.

When an outgoing call is made - this performs a registration.

The network can also 'page' the phone, both for incoming calls and to send you callback messages. The paging can also occur to get the phone to reregister.

Both networks have the facilities to try and help you with regards to coverage in your area, etc. Ring the operators from the cellphone.

Who are the 'People's phone'?

People's Phone is a service of Cellular Communications Corp., a Vodafone and Cellnet service provider.

People's Phone claim to offer a "better" deal for cellular phone users. They have a generally reasonable air-time contract, with various guarantees as to no increases etc., and attempt to be down-to-earth and trustworthy. Their marketing is targetted at (1) people who don't understand the wide variety of services and contracts in the cellular industry and (2) people who've had their fingers burned with other companies.

Of particular note is their "Quota" system. You agree (in advance) a limit to your call charges each month. When you reach that limit, the network inhibits further outgoing calls until the beginning of the next billing period. Incoming calls still work. You can change this Quota at any time.

Some other features of their system

How can I check the status of a GSM or PCN phone's divert and call waiting?

The *# codes are specified in the GSM standard and thus apply to all GSM and PCN phones.

 F1 -> menu -> determine divert status

 *#21# to check number for "All Calls Divert"
 *#67# to check number for "On Busy Divert"
 *#61# to check number for "On No Reply Divert"
 *#62# to check number for "Divert if unreachable (off or out of range)

 *#43# to check call waiting status. 

 To set divert:
 ** 21*number#
 ** 67          On Busy Divert
 ** 61          On No Reply Divert

What facilities are present in GSM and PCN handsets (like Orange and One2One) to counter 'phone thieves?

The new breed of GSM/PCN mobile phones use a Smartcard or SIM. This makes it possible to use any valid card in your phone. It also means that the phone number will change depending on the card. Both the mobile and SIM are validated before a call is set up. Therefore if the mobile is reported stolen it won't work even with a valid card. GSM and PCN both make use of encryption.

[Robin Fairburns writes:]

The security applies to the air path between the mobile and the base station ... and it's not as strong as they would like you to believe -- someone with the sorts of resources that GCHQ has can crack it in some modest number of minutes. If you think about it for a moment or two, you'll realise that the only way you could have an encrypted path right the way to the receiving telephone would be if that had decryption capability. On the whole, I would prefer a mobile that let me call anyone to one that was "in principle" totally secure.
It'll deter the casual idiot with his mobiles scanner, however. Legally speaking, the landline can only be tapped in course of engineering work (information gained from which should not be allowed to propagate), or subject to a warrant signed by the home secretary.
Of course
- a) if you believe that you'll believe anything, and - b) if you trust _him_, you probably don't care about the government having free access to any calls you make.

What are the functions possible with Hutchison's Voice messaging service?

After you've keyed in your PIN etc.

Message retrieval

 2      delete last msg
 3      play messages most recent first
 4      play messages oldest first
 5      replay last msg heard
 6      play all msgs
 7      play time and date information
 9      forward msg (enter mailbox number followed by #)

Extended forwarding

 13     to enter extended forwarding
        2       confirm msg to be forwarded
        7       to prepend a comment
        9       to append a comment
        5       to listen to complete message with comments
        6 followed by # to actually send the message
        10      to return to normal message retrieval mode.

What are the phone numbers for the GSM network SMS 'message centres'.

Key MT = Mobile Terminated SMS MO = Mobile Originated SMS Text = text-based input TAP = Telocator Alphanumeric Protocol (a paging standard)

Inter-network codes Incoming: Mobiles from this network can be sent messages from external SCsOutgoing: The SC on this network can send messages to mobiles connected to other networks RemoteSC: Mobiles on this network can send MO messages to SCs on other networks UK-in: Network can receive SMS messages from UK OLO SCs UK-out: SC can send SMS messages to UK OLO subscribers

DTMF access to MT Vodafone 0385 490490

Modem access to MT Vodafone 0385 499499, Text, 7E1, 2400 Cellnet 0860 980480, TAP, 8N1, 14400 Orange 0973 100602, Text, ?, ? One2One ?, TAP, ?, ? (on test)


 Orange ?
 One2One ?
 Cellnet Incoming, Outgoing, RemoteSC
 Vodafone RemoteSC

MO to MT Vodafone +44 385 016 005 Orange +44 973 100 973 {*} Cellnet (on test), ? One2One ?

MO to elsewhere Vodafone Paknet Orange ? Cellnet ? One2One ?

Version: 2.10 Last-modified: Time-stamp: <96/05/12 23:04:20 jrg>