UNIVERSITI TEKNOLOGI MALAYSIA - FKE - UTM

13module’ (SIM). For GPRS, the ME has to be equipped with packet transmissionabilities. There are three classes of GPRS equipment:i. Class A: equipment that can handle voice calls and packet data transfers atthe same time.ii. Class B: equipment that can handle voice or packet data traffic (but notsimultaneously) and can put a packet transfer on hold to receive aphone call.iii. Class C: equipment that can handle both voice and data, but has todisconnect from one mode explicitly in order to enable the other.2.5 Short Messaging ServiceSMS stands for Short Messaging Service. It is the technology of enable thesending and receiving of messages between mobile phones. SMS first appeared in1992. It was included in the GSM standards right at the beginning. Later it wasported to wireless technology like CDMA and TDMA. The data that can beobtained by an SMS message is very limited. One SMS can contain at most 140bytes (1120 bits) of data. So, one SMS can contain up to 160 characters if 7-bitcharacter encoding is used and 70 characters if 16-bit Unicode UCS2 characterencoding is used. SMS text messaging supports languages internationally. It worksfine with all languages supported by Unicode including Arabic, Chinese, Koreanand Japanese. Besides text, SMS messages can also carry binary data. It is possibleto send ringtones, pictures, operator logos, wallpapers, animations, business cards(e.g. VCards) and WAP configurations to a mobile phone with SMS messages.There are many different kinds of SMS applications on the market todayand many others are being developed. Applications in which SMS messaging canbe utilized are virtually unlimited. Some of them are:i. Person-to-person text messaging.ii. Provision of information.iii. Downloading.