ServersCAP Polling Calculator 1.0 - Specifics

CAP Polling Calculator 1.0 – Specifics

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Michael Niehaus


The Variables

To get a reasonable idea of how much network traffic your SMS clients are generating
when checking for new advertisements, please fill in the following details. If you have any
questions about the specific values, see the “Explanation of Variables” section below.

The Variables

To get a reasonable idea of how much network traffic your SMS clients are generating when checking for new advertisements, please fill in the following details. If you have any questions about the specific values, see the ‘Explanation of Variables’ section below.

Limitations in version 1.0: Only machine-targeted calculations are currently supported.
Calculations for user- and group-targeted advertisements will be added at a later date.

Total SMS client machines:
Total number of packages:
Total number of advertisements:
Number of machines targeted:
Expected number of machine-targeted advertisements per machine:
Expected number of group-targeted advertisements per machine:
Expected number of user-targeted advertisements per machine:
Number of user groups targeted:
Number of users targeted:
Client polling interval (minutes):


Explanation of Variables

Total SMS client machines

All SMS client machines will poll an SMS server’s client access point (CAP) at the specific
polling interval, as long as the client machine can access the CAP (the obvious time when they
won’t: when they are turned off).

Total number of packages

SMS creates two files and a directory in the “CAP_XXXPkgInfo.box” directory for each package
defined to SMS. One of these files (the “.NAL” file) contains a list of distribution points the
package can be loaded from. The second file (the “.PKG” file) contains the details for the package:
name, description, programs (and their command lines), etc. The directory (the “.ICO” directory)
contains any custom icons defined for the programs associated with the package.

Each of these files and directories increases the number SMS must scan when looking for a particular
package. Due to the number of these directory scans, the amount of traffic generated in the process of
doing this really adds up.

Total number of advertisements

Each advertisement results in one file in the “CAP_XXXOfferInf.box” directory (the “.OFR” file).
This file contains details about the advertisement, such as the package associated with it, the
availability and expiration dates, etc.

Each of these files increases the number SMS must scan when looking for a particular
advertisement. Due to the number of directory scans resulting from this, the amount of traffic
generated in the process of doing this really adds up.

Number of machines targeted

While all machines will poll for advertisements, not all will find any. Those that are targeted by
at least one advertisement will find an instruction file in the “CAP_XXXOfferInf.box” directory
(the “.INS” file). A directory scan is required to locate this instruction file.

All machines, regardless of whether they have been targeted, will read the “CAP_XXXOfferInf.boxXXXSYSTM.LKP”
machine lookup file to determine whether an instruction file exists for that machine; there is no
direct correspondence between the name of the instruction file and the machine.

Expected number of machine-targeted advertisements per machine

No, that’s not a typo: packages can be advertised to a machine through one of three ways:
directly at the machine, based on the client’s user group membership, or based on the client’s user ID.

This value should include only those advertisements targeted at an average machine. This value corresponds
to the number of entries found in the machines instruction file (“.INS” file), and has a strong
influence on the overall traffic.

Expected number of group-targeted advertisements per machine
Expected number of user-targeted advertisements per machine

Packages targeted at a group or user work differently than those targeted at a machine. The client machine
must check the proper lookup file (“XXXUSRGRP.LKP” or “XXXUSER.LKP”) to determine which of the groups (from the list of
groups the logged-on client belongs to, or the client’s user ID) have advertisements associated with them.

Each entry found in either of these files generates additional network traffic. (The amount is about the same
as that generated by each entry in the machine’s “.INS” file, containing the list of
machine-targeted advertisements.)

Number of user groups targeted
Number of users targeted

Each targeted user group or user will create another file in the “CAP_XXXOfferInf.box” directory, which affects the
amount of network traffic generated by each scan of this directory (for any purpose).

These files are also read by the client machine for each user- or group-targeted
advertisement and must themselves be located (again via a directory scan).

Client polling interval

The easy one: this specifies how often, in minutes, the SMS client will check the CAP for new
advertisements. The default value is 60 minutes, but can be as low as 15 minutes or much higher.
Setting this value too low can create excessive network traffic – it serves as a multiplier for all
the other variables.

This is version 1.0 – some of the values may not be 100% correct. However, they should be
close – please do not use these as anything more than an order-of-magnitude estimate.


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