keys.me

speech signal process tools

.lo
.SJ "Living with the Entropic License Manager System"
.AU "Alan Parker"
.TM ETM-S-91-xx:rap 1.2 1/22/93
.sh 1 "Introduction"
.pp
Instead of requiring that a given software license
be associated permanently with a given CPU,
Entropic uses a floating license system 
that can assign software licenses dynamically as needed to any 
host on a network.
This document
describes how this system works, provides guidelines for setting it up,
and provides information to help solve common problems.
.sh 2 "Goal of the License Manager System"
.pp
The license manager system is a technical means of implementing our
software licensing policy.   Our current policy is to license
\fIwaves+\fR on a per-user basis and ESPS on a
per-host basis.   In the case of \fIwaves+\fR the license manager will
allow no more than the licensed number of \fIwaves+\fR to be running at
any one time on the network.  
A \fIwaves+\fR license is checked out automatically when \fIwaves+\fR is
run, and checked back in when \fIwaves+\fR terminates.
In the case of ESPS, a license must be
checked out
for a particular host before anyone can run ESPS programs on
that host.  Until the license is checked back in, any ESPS programs can
be run on that host by any user (given that ordinary Unix file permissions
are appropriate).
The ESPS license is checked out for a host in one of two ways.  It can be explicitly
checked out by the user by using the command \fIecheckout\fR, or simply by running 
an ESPS program.   If an ESPS program is run, and the required license is not checked 
out on the host, then the program will attempt to check it out.  If that succeeds, then
a license is checked out on that host until it is freed by the user.
.pp
Our reasoning for the distinction between the (per-user) \fIwaves+\fR
licensing and the (per-host) ESPS licensing is as follows:
Unlike
\fIwaves+\fR, the typical ESPS program only runs for a short time period
and does not provide an environment in which the user remains for an
extended period.
Most ESPS programs are command line oriented and can be used in Unix
shell scripts.  Therefore, if we had each ESPS program check out and free a
license (as \fIwaves+\fR does) it would be possible for scripts to fail
in unpredictable ways, since a license might a taken away between steps
within the script.   Our solution to this is to have a program which
checks out a license and one to free license.   During the time that a
license is checked out for a given host, any ESPS programs can be
run on that host.    It does not matter how many users there are on
that host or how many of those users are running ESPS programs.
.pp
The Entropic License Manager System consists of the following major
components: \fIelmd\fR, \fIelmadmin\fR, \fIecheckout\fR,
the license keys, and the various ESPS user programs.   
.sh 2 "How It Works"
.pp
The license manager daemon (\fIelmd\fR) is started and left running for
as long as any Entropic programs are going to run.  It is normally
started at boot time and simply left running forever.   When a client
program requests a license, the license manager checks the key files
and determines if any licenses of the requested type remain.  If so,
then the count of available licenses is decremented and the requesting
process is granted permission to continue.
.pp
Client programs communicate with the license manager with the
same facility used by the
network file system (NFS), so any system that supports NFS should be
able to run our license manager system.
.pp
The client programs can be on a different host than the one
running the license manager daemon (\fIelmd\fR).  But in this case, the client
programs must know which host is running \fIelmd\fR.
This information is passed to the client programs via the Unix
environment variable \fBELM_HOST\fR.   It is simply set to the name of
the network host running \fIelmd\fR.   
.pp
As mentioned earlier, \fIwaves+\fR checks out a license each time it is
started and frees that license when it exits.   ESPS programs (all other
programs except \fIwaves+\fR and its attachments) check to see if an ESPS
license is checked out before they run, but they do not check out the
license themselves.   The program \fIecheckout\fR 
checks out an ESPS license and then holds it (by putting itself
into the background).    The license is freed by causing \fIecheckout\fR
to exit.   A program is provided to do this; \fIefree\fR.
Under certain conditions this program can fail to find \fIecheckout\fR.
In this case, someone will have to find the \fIecheckout\fR with
\fIps\fR and kill it manually.
.sh 2 "Network Timeout"
.pp
The client programs (that is all ESPS programs and \fIwaves+\fR) will
timeout in a default 10 second interval if they cannot get a response
from the license manager daemon.   This should be enough time for all
but the busiest networks.  However, we have provided a means to allow
users to adjust this timeout interval.  The environment variable
\fBELM_TIMEOUT\fR can be set to the desired timeout interval (integer
values only).   So, for example, to set the timeout interval to 15
seconds do \fIsetenv ELM_TIMEOUT 15\fR.  (Or whatever works with your
shell.)
.sh 2 "Waves Related ESPS Programs"
.pp
There is a set of ESPS programs 
that provide conversion support and are included with the \fIwaves+\fR
product.
These programs will run if a network has a valid \fIwaves\fR license installed.
No license need be explicitly checked out for these programs.
There is no limit to how many hosts these programs can be used on.
These programs are: addfea, addfeahd, addgen,
bhd, btosps, comment, fea_element, featosd, formant, hditem,  hdshrink,
ils_esps, mu2esps, pplain, psps, sdtofea, sgram, sigtosd, testsd, splay,
and tofspec.   
.sh 2 "User Written Programs"
.pp
User written programs compiled and linked with the ESPS libraries will
be under the Entropic license manager system.   These programs will only
run if an ESPS license is checked out.   Also, if a site has a source
license to ESPS and recompiles any of the above mentioned \fIwaves+\fR related
programs, then they revert to the ESPS license rules; that is they will
only run if an ESPS license is checked out.  
.sh 1 "License Manager Setup"
.pp
The product installation instructions give sufficient information for
the general installation of all of the software, including the license
manager system.   Before installing the software, you 
must decide which host is to run the
license daemon (\fIelmd\fR).   While this can be any host that is
reachable on your network, there might be local considerations that make
one host better or worse than others.   Often the central server machine
(if there is one) is the logical choice. Note that the license manager need 
not run on the same host which stores the ESPS files.   A poor
choice of a machine to run \fIelmd\fR on would be a machine behind
several network bridges, one that tends to be down often, or one that might
be considered a personal machine by a particular user.
.pp
Once you decide which host will run \fIelmd\fR, you
need to get keys made for that host.   Note that the keys are bound to a
particular host, so that once the keys are made, they and \fIelmd\fR
cannot be moved to another host (for obvious reasons).  Of course, if
you have legitimate reasons for moving \fIelmd\fR and the keys to
another host, we will give you new keys.   To install the keys, you must
first run the program \fIelmadmin -c\fR which generates a server code
that you provide to us.
We take this server code, along with the information about what you
bought, and generate a key.  
.pp
The best way to communicate the server code to us is via email or FAX.
It is best if an actual Unix \fIscript\fR listing of the \fIelmadmin
-c\fR output is sent.  This greatly reduces the chance for errors in
copying the server code.   Voice telephone can be used, but it is 
more error prone.
.pp
After the keys are installed \fIecheckout\fR and \fIwaves+\fR should run
(if the proper keys were installed).   When running on a different host
than \fIelmd\fR is running on, then the environment variable
\fBELM_HOST\fR must be set to the hostname of the host running
\fIelmd\fR.    
.sh 2 "ELMD Initialization"
.pp
The license manager daemon, \fIelmd\fR, will not issue licenses for
about three minutes after it first starts up.   If you try and run a