Sms Performance On Sdcch

EXECUTIVE SUMMARY

Short Message Services is a growing and promising alternative choice for all kind of users and for a diverse type of new business ideas, starting from third party suppliers to corporate users or a fast set of alarms only for half duplex communication requirements.

Because of fact that this service use existing resources in the network we need to provide tools for the write measurement and supervision. This implies that some areas need to be review constantly on monthly basis, such as SDCCH traffic, BHSM with BHCA, SMS traffic and SMS error distribution. Therefore we demonstrate within this paper the steps and considerations that need to be taken in order to create targets and thresholds require for a fast countermeasure and forecast.

TABLE OF CONTENTS

A INTRODUCTION 3

1. Business Challenge 3

2. Intention 3

3. Scope 3

C PRESENTATION 4

1. SMS actual architecture 4

1.2 Performance End to End 5

1.3 RF resources 8

2. Tendencies 16

A INTRODUCTION

1. Business Challenge

The short message service (SMS) permits users to send and receive text messages to/from their mobile phones. SMS was introduce in 1992 and, since then has experience a remarkable success: xxx millions of messages are sent per month.

2. Intention

In the paper, we evaluate our architecture for SMS delivery performance and management. In our present model the performance depends on different platform services functionalities and network environment, rather than a more flexible and dynamically approaches to define maximum acceptable loss of messages of a non-guaranteed SMS service class, thereby controlling the trade-off between minimal message loss and maximum throughput in the pipelines to improve this service. In Paraguay SMS usage is increasing rapidly as more and more subscribers preferred as a normal way of exchanging ideas and chatting to friends or colleagues. Apart from good volumes on normal days, SMS usage reaches abnormally high peaks on special days and during normal peak days of the week.

A natural question that arises when one sees such phenomenal usage of this service is: What happens to the performance of this services volumes increase beyond expectations? Or, how are other services that are provided on the same network affected, with increasing SMS usage?.

3. Scope

This document cover technical aspects of SMS utilization performance and trends, in which we propose thresholds in dimensioning and selection for alternatives in superpose networks that absorb and enable parallel growth.

C PRESENTATION

1. SMS actual architecture

1.1 Network architecture.

Network architecture relays on SMS over GSM. This implies that all the MO-SMS and MT-SMS will use a SDCCH to reach destination. The message use all CS connection path to the MSC and towards the SMSC вЂ" Converse platform.

The networks elements involve in the transfer of short message are shown in the figure above. The figure present the steps involve in delivering a MT-SM to an MS.

1. A MT-SM will start from the Service Center then will be forwarded to a gateway MSC or in this case MSCBAR1 where the HLR is collocated.

2. The HLR will locate the MS by querying the HLR forward it to the appropriated MSC. MSCPER2, MSCARE3 or MSCSAN

4. The VLR in turn provide the information where the subscriber destination area is and deliver the message to the MS.

The SMS at this level is carried on either SDCCH or SACCH depending on the use of traffic channel. When TCH is not allocated, i.e., no voice call or data transfer in progress, the short message is carried on the SDCCH.

If a TCH is allocated before a short message transfer starts, the Short message use the SACCH associated with the TCH. If a TCH is allocated during a short during a short message transfer on an SDCCH (i.e., a voice call or data transfer during short message transfer), the transaction stops and continues on the SACCH associated with the TCH. If the voice call or data transfer ends during short message transfer, the short message may either continue on the SACCH associated with the TCH or may stop and continue on the SDCCH.

The sequence of messages exchange is similar to that of the voice call set-up. In the case of SMS messages transfer when the Traffic channel is not allocated, the SDCCH is not released after authentication, ciphering and routing but is retained for sending or receiving the message. The time for which the SDCCH is held is calculated in the next section.

1.2 Performance End to End

The performance of the SMS at system level is calculated using the following concept:

This relation is base on all messages End to End, reported by the system (MSC) at daily total values

According to the Graph the performance End to End of SMS is stable in around 86% and increasing. Breaking this indicator in two branches, MO-SMS (Mobile originating Short Message) and MT-SMS (Mobile terminating Short messages), will help us to do a deeper analysis to the whole process identifying the sections where the bottleneck might be.

The Performance indicator is calculated base on MSC counters. Those counters are collected daily using the total of the day. This method is useful for the optimization point of view to analyze worst performance trends and pure problems without the congestion variable.

One of the branches we will present in the next figure