1. What is a session?

 

As a general rule, the term "session" describes a temporary connection established between a client and a server. In this case the clients are any of your devices logging into the mdex network via mdexfixed.IP and the server is the mdex radius server, i.e. the authentication service for users logging on.

 

An mdexfixed.IP sessions begins whenever the mdex radius server has authenticated a device logging into the network and finishes when the connection between the client and server ends.

An mdex session is not identical with a random GPRS session established by your mobile device. When it logs into the mdex network there are, however, interdependencies between an mdex session and a GPRS session, thus some conclusions reached abouth the mdex session can also be applied to the GPRS session (for more information click here).

 

 

2. What do I need session information for?

 

You expect specific communication characteristics from your system, such as "always online" or dial-up connections at certain intervals or at certain times, as well as the transmission of certain "payload" data volumes.

 

Session information helps you to monitor whether your system is performing as expected in terms of its communication characteristics. Should, for e.g., your expect "always online" but the Session Monitor shows hundreds of sessions per month this could be an indication that the mobile network router settings are incorrect or that there are problems with network coverage or the antenna causing unintentional session aborts.

 

 

3. What information can the Session Monitor provide?

 

The Session Monitor displays the following data:

• The device ID with the alias you have assigned to it.
• The number of sessions logged.
• The total duration of the sessions (in the format hh:mm:ss), i.e. the total sum of session times recorded during the reporting period.
• The number of bytes received by the device and/or the data volume actually transmitted from the server to the device.
• The number of bytes transmitted by the device and/or the data volume actually received by the server from the device. 

 

 

4. Does the Session Monitor show me the GPRS volume my network provider will bill me for?

 

No, the Session Monitor shows the information recorded by the radius server (authentification service for users logging in). This information only reflects the real data volumes measured on the mdex server. Depending on the tariff, the network provider, however, rounds up the data per session to the next 1, 10 or even 100 Kbytes (data block rounding). This can lead to significant discrepancies between the data volumes actually transmitted and the volumes billed by the network provider. Thus it can make financial sense not to end a session every time single data units have been transmitted, but rather to maintain it for a longer period.

 

Another discrepancy between the data volumes shown by the Session Monitor and those stated on the invoice can result when data connections are not established via the mdex APN but instead via another. Should, for example, the network provider's standard Internet APN be used for a non-mdex service then this volume will appear on the mobile network invoice but not on the mdex Session Monitor.

 

 

5. How can I use the session data to optimize my GPRS data consumption?

 

If the information provided by the Session Monitor is significantly different to what you would expect, alarm bells should ring, because the discrepancy could be a sign of an error or a less than optimum configuration.

Typical examples for this are:

 

• A significantly higher number of sessions than the number of days covered by the report: To achieve optimum data block rounding (definition: see here) you should make full use of the block rounding steps. Depending on the tariff, block rounding takes place on an hourly or daily basis. If, in the case of daily block rounding, serveral data transmissions are planned then it makes the most sense not to end a connection after each transmission, but rather at most once every 24 hours so that the sum of the data volume transmitted is rounded up instead of each individual transmission.
• A significantly higher number of sessions than you expected: Could there be an error in the network or the device which allows a proper connection to be established but disrupts the actual data transmission? Is the application expecting something and thus keeps setting up frequent connections?
• A significantly higher data volume than you expected: Maybe the data is being transmitted more than once which is unnecessary?

 

 

6. Does the Session Monitor display all session data?

 

No, the Session Monitor only displays data for sessions which were correctly ended. Thus ongoing sessions are not be displayed. The same applies for sessions which were interrupted due to a sudden power cut or to equipment or software defects.

 

 

7. How up-to-date is the session data in the Session Monitor?

 

The Session Monitor provides data almost in real time and for correctly ended sessions - i.e. there is no information for ongoing sessions.

 

 

8. What happens if I change the SIM card in a device?

 

Session information is linked to the mdex access point. This is authenticated via the access data, not via the SIM card. We therefore ignore the substitution of one SIM card for another one within the same network. The session data continues to be assigned to the device used for access. Thus in the case of a card substitution the mdex session data can relate to multiple SIM cards.