SMSC
SMS & SMSCPresented By:Vikas MiyaSMS OverviewSMS stands for
Short Message ServiceSMS is the ability to send and receive short
alphanumeric messages to and from mobile telephones.SMS works on
store and forward methodBesides text, SMS messages can also carry
binary data. It is possible to send ringtones, pictures, operator
logos, wallpapers, animations, business cards and WAP
configurations to a mobile phone with SMS messages.
SMS OverviewOne SMS message can contain at most 140 bytes (1120
bits) of data, so one SMS message can contain up to:160 characters
if 7-bit character encoding is used (suitable for encoding Latin
characters like English alphabets.)70 characters if 16-bit Unicode
UCS2 character encoding is used (SMS text messages containing
non-Latin characters like Chinese)SMS text messaging supports
languages internationally lie Arabic, Chinese, Japanese and
Korean.
Concatenated/Long SMSOne SMS message can only carry a very
limited amount of data. To overcome this drawback, an extension
called concatenated SMS A concatenated SMS text message can contain
more than 160 English characters.The sender's mobile phone breaks
down a long message into smaller parts and sends each of them as a
single SMS message.The recipient mobile phone will combine them
back to one long message.SMSC OverviewSMSC stands for Short message
service centerSMSC is a network element in the mobile telephone
network which delivers short messages (SMS)SMSC works on store and
forward principle i.e. when a user sends a text message to another
user, the message gets stored in the SMSC which delivers it to the
destination user when destined user is available.SMSC Overview An
SMS center (SMSC) is responsible for handling the SMS operations of
a wireless network.When an SMS message is sent from a mobile phone,
it will reach an SMS center first. The SMS center then forwards the
SMS message towards the destination. The main duty of an SMSC is to
route SMS messages and regulate the process. If the recipient is
unavailable the SMSC will store the SMS message. It will forward
the SMS message when the recipient is available.
Network Architecture
SMS technical realization The SMS is realized by the use of the
Mobile Application Part (MAP) of the SS#7 protocolThese MAP
messages may be transported using 'traditional' TDM based
signaling, or over IP using SIGTRAN and an appropriate adaptation
layer.SMS on Store and forward technique.SMS Call FlowBasic SMS
Call Flow :End to end SMS transaction completes in 2 parts :Message
submission by originating subscriber to its SMSC (Mobile
Originating Part)Message delivery by SMSC to recipient Subscriber
(Mobile terminating Part)
9SMS Call Flow
MO-SM SubmitThe SM is sent from the originating Mobile Station
(MS) to the serving Mobile Switching Center (MSC). The address of
the SMSC where the SM should be submitted to is stored on the SIM
card of the subscriber and forwarded to the MSC with the
message.The MSC forwards the SM to the SMSC. The SMSC returns a
positive (ACK) or negative (NACK) response indicating whether the
message was successfully stored of not.
MT-SM DeliverTo delivers a SM SMSC has to find out the location
(serving MSC) and the International Mobile Subscriber Identity
(IMSI) of the recipient subscriber first. This information (routing
information) is retrieved from the Home Location Register (HLR) of
the recipient subscriber based on the recipient number (MSISDN).
HLR Provides routing Information to SMSC, which includes IMSI and
serving MSC of recipient number. Based on routing information SMSC
delivers SM to the serving MSC and MSC forwards it to the recipient
Mobile Station.
