Hacking Voice Mail Systems

Voice Mail is a relatively new concept and not much has been said about it.
It is a very useful tool for the business person and the phreak.  The way it
works is that somebody wishing to get in touch with you calls a number,
aometimes a 1-800, and punches in on his touch-pad your mailbox number and then
he is able to leave a message for you.  Business experts agree that this
almost totally eliminates telephone tag.  When a person wishes to pick up his
message all he needs to do is call the number enter a certain code and he can
hear his messages, transfer them, and do other misc. mailbox utilities.

Most VMSs are similar in the way they work.  There are a few different ways
the VMSs store the voice.  One way is that the voice is recorded digitally and
compressed and when heard it is reproduced back into the voice that recorded
it. Another method that is slower and uses more space, but costs less, stores
the voice on magnetic tape, the same type that is used to store data on a
computer, and then runs the tape at a slow speed.  Using this method the voice
does not need to be reproduced in any way and will sound normal as long as the
tape is running at a constant speed.  On some of the newer VMSs the voice is
digitally recorded and is transformed from the magnetic tape at about 2400
bits per second.

There are many different types and versions of voice mail systems.  Some of
the best and easiest to get on will be discussed.

Centagram
These are direct dial (you don't have to enter a box number).  To get on one
of these, first have a number to any box on the system.  All of the other
boxes will be on the same prefix; just start scanning them until you find one
that has a message saying that person you are calling is not available.  This
usually means that the box has not been assigned to anybody yet.  Before the
nice lady's voice tells you to leave the message, hit #.  You will then be
prompted for your password.  The password will usually be the same as the last
four digits of the box's number or a simple number like 1000, 2000, etc.  Once
you get on, they are very user friendly and will prompt you with a menu of choices. 
but the system administrators box, which will usually be 9999 on the same
prefix as the other boxes, will allow you to hear anybody's messages and
create and delete boxes.

Sperry Link
These systems are very nice.  They will usually be found on an 800 number.
These are one of the hardest to get a box on because you must hack out a user
ID (different from the person's box number) and a password.  When it answers,
if it says, "This is a Sperry Link voice station.  Please enter your user ID,"
you will have to start trying to find a valid user ID.  On most Sperrys it
will be a five digit number.  If it answers and says, "This is an X answering
service," you first have to hit *# to get the user number prompt.  Once you
get a valid user number will have to guess the password on most systems, it
will be 4 digits.  Once you get in, these are also very user friendly and have
many different options available.

RSVP
This is probably one of the worst VMSs but it is by far the easiest to get
yourself a box.  When it answers you can hit * for a directory of the boxes on
it (it will only hold 23).  If you hit # you will be given a menu of options
and when you choose an option you will then be prompted for your ID number.
The ID number on an RSVP system will just about always be the same as the
mailbox number, which are always only 2 digits.

A.S.P.E. N.
The Aspen voice message systems made by Octel Telecommunications is in my
opinion the BEST VMS made.  To get a box on an Aspen, you need to find an
empty box.  To find an empty box, scan the box numbers and if one says, "You
entered XXXX.  Please leave a message at the tone," then this is an empty box.
You next just press # and when prompted for your box number enter the number
of the empty box and friendly voice of the nice lady will guide you through
all of the steps of setting up your box.  She first tells you what you can do
with the box and then will prompt you with, "Please enter the temporary
password assigned to you by your system manager."  This password will usually
be 4 digits long and the same as the box number like 1000, etc.  Once you get
on their are many things you can do.  You can make a distribution list where
if you want to leave a certain message to more than one person, you can enter
the list number and all of the boxes on the list will get the message. You can
also have the system call you and notify you that you have new messages. These
systems also have what they call "Information center mailboxes" that are
listen only and can also have a password on them so the person calling has to
enter the password before he hears the greeting message.  Aspen VMSs have a
system managers mailbox that will just about give you total control of the
whole system and let you listen to people's mail, create and delete boxes, and
many other things.