The Telecom Protocols

The Signalling Connection Control Part (SCCP) message are used by the peer to peer protocol. Following are the SCCP message used by the peer to connection oriented and connection less services. Application that uses the service of SCCP are called Subsystems. Refer the  SCCP structure for detail SCCP structure. Classes of service : • Class 0 —Basic connectionless class - it has no sequencing control. i does not impose any condition on SLS, therefore SCCP message can be delivered in out-of-sequece. • Class 1 —In-sequence delivery connectionless class - it adds the sequence control to class 0 service by requiring to insert the same SLS to all NSDU. • Class 2 —Basic connection-oriented class - Assign the local reference numbers (SLR,DLR) to create logical connection. it does not provide the flow control, loss, and mis-sequence detection. • Class 3 —Flow control connection-oriented class - Class 3 is an enhanced connection-oriented service that offers dete...

Why LTE?  The first question came into mind is why LTE? we are having 2G and 3G well established in market, then what is the requirement of LTE or so called 4G. But before proceeding let me clear LTE is not considered as 4G but the 3.9G due to some limitation. To answer the question, the subscribers and business users are discovered the power of wireless broadband through the advanced phones. Today internet are used for video streaming, live video, You Tube,  Maps, Social Sites and web search. Because of so much to do on internet, consumers wants the high speed in data transfer on the go and the solution is LTE. The standards of LTE developed by 3GPP. LTE Provides following features and application for users and business: Improve QoS by decreasing the latency time. provide the connectivity for non-traditional device like cars provide the communication, entertainments, personal assistance. Improving the services Reducing th...

For call related message, there are two type of solutions defined for portability Domain: A. Mobile Number Portability-Signaling Relay Function (MNP- SRF): it is based solution acts on SCCP addressing and also makes use of NP database. B. IN- Related Solution : IN based solution allows the MSCs to retrieve routing information from NPDB. A. Mobile Number Portability-Signaling Relay Function (MNP- SRF) Scenarios: Figure-  Call related case - Signalling Relay Function (SRF) solution Call A.1 : Call to a non-ported number : Fig 1:  Call to a non-ported number  From an Originating Exchange a call is set up to MSISDN. The call is routed to the subscription network being the number range holder network, if the number is non-ported. When GMSCa receives the ISUP IAM, , it requests routing information by submitting a MAP SRI to the MNP_SRF/MATF.  When the MNP_SRF/MATF receives the message, the MNP_SRF/MATF analyse...

H.248   is protocol used between the MGC and MG in Master-Slave fashion. MEGACO is similar to MGCP. MGC uses this protocol to control the MG. MEGACO  provide the following enhancement over the MGCP. - Support multimedia and multi point conference enhanced service. - Improve syntax for more efficient semantic message processing. - TCP and UDP transport support - Support either binary or text encoding. Message Structure: Message {  Transaction {     Action {         Command {            Descriptor {                Package {                     Property { }}}}}} MTACDPP … Message : Multiple Transactions can be concatenated into a message, which contains header, the version...

Mobile Number Portability (MNP): Mobile Number Portability (MNP) is the ability for a UMTS or GSM mobile subscriber to change the subscription network within a portability domain while retaining her original MSISDN. Fig 1: General Architecture of Portability for Calls  Few Definitions to understand the MNP feature:  Number Range Holder Network (NRHN):  The Network to which number range containing the ported number has been allocated.  For Example if a number which is in process of porting is belongs to Vodafone network, then the Vodafone treated as Number Range Holder Network (NRHN).  Donor Network : A subscription network from which a number is ported-out in porting process. This may or may not be the Number range holder network.  For example if a subscriber is ported-out from Vodafone to Airtel, then Vodafone  network if called as Donor network. If this number range belongs...

Session Initiation Protocol (SIP) SIP stack handled over the following layer and data transfer based on following Internet Media Protocol stack: Application Layer: H.232, SIP, RTP, DNS, DHCP Transport Layer: TCP, UDP Internet Layer: IP Physical Layer: ATM, V90, Ethernet, Wireless 802.11 1. Physical Layer : it can be following:         - Ethernet LAN,         - DSL,         - ATM         - Wireless 802.11 network. 2. Internet Layer : used to route the packet across the network using the destination IP address. IP offers following functionality and drawbacks with simplicity:  -- Connection less  -- Best-effort packet delivery protocol.  -- IP packets can be lost  -- IP packets can be delayed  -- IP packets cab be received out of sequence.  -- IP packet are not Acknowledged. IP Address used over the public internet are assigned in blocks by the IANA (I...