The diagram below shows how ESME is connected to the SMSC via the SMPP server (SMPP gateway).

Fig: ESME to SMSC Interconnection (click to enlarge)

The SMPP Agent (process) is responsible for maintaining the communication link with the ESME, accomplishing the conversion of the SMPP standard message and the internal message of the SMSC ( Short Message Service Centre ) system, and providing the external short message entity (ESME) with the open interface to access the SMSC system. The current version of SMPP protocol is 3.4  (SMPP3.4).

As explained in the communication between ESME and SMSC servers post, there are two transmission modes between ESME and SMSC servers, namely-

1. Transmitter Mode
2. Receiver Mode

The following diagram explains the role of SMPP server during the connection establishment and release between the ESME server and SMS server

Transmission Mode:

Fig: Role of SMPP server during transmission mode(click to enlarge)

In the figure,

Fig: Role of SMPP server in Receiver Mode(Click to Enlarge)

In the figure:

•Steps (1) to (4): ESME is bound with SMSC in Receiver mode and is ready to receive short messages from SMSC;

•Steps (5) to (8): SMSC distributes a short message to ESME.

•Steps (9) to  (12): Disconnect the link between ESME and SMSC.

• Method of the ESME to access the SMSC

Fig: ESME and SMSC Communication

Interworking between the SMSC and ESMEs are categorised as:

1. Messages from ESMEs to the SMSC
2. Messages from SMSC to ESMEs

• Transmission mode between ESME and SMSC

There are two transmission mode between ESMS and SMSC

1. Transmitter Mode
2. Receiver Mode

1. Transmitter Mode

Fig: Messages between ESME and SMSC

• Major Operation between ESME and SMSC

The major operation between ESME and SMSC are:

1. Bind operation
2. Unbind operation
3. Submit_SM operation
4. Deliver_SM operation

Bind operation is carried out to connect ESME server and SMSC server. Unbind Operation is carried out to release connection between ESEM server and SMSC server. Submit_SM and Deliver_SM are operation carried out to send and deliver short message between ESME and SMSC server. There are two types of bind operation:

1. Bind_Transmitter
2. Bind_Receiver

All these operation process is explained below with figure.

The figure below illustrates the process of bind_transmitter operation between ESME and SMSC servers.

Fig: Bind_Transmitter (Bind Process between ESME and SMSC servers)

The figure below illustrates the process of bind_receiver operation between ESME and SMSC servers.

Fig: Bind_Receiver Process between ESME and SMSC

The figure below illustrates the communication process between ESME server and SMSC server for transmitting and receiving Short Messages

Fig: Short Message transfer between ESME and SMSC

Thus mobile user sends sms to ESME and is then send to by that ESME to the SMSC server and the bill is generated by counting the number of SMS send or received. The SMS count for each ESME account is identfied by the SMS short code given at the time of interconnection of the ESME and SMSC. The amount per SMS is subject to business policy between the two SMS service provider.

This article first explains the CRBT call flow in a mobile network , then a block diagram explaining the CRBT system connection to other parts in IN(Intelligent Nework). Finally the CRBT system hardware and software itself is explained.

Suppose subscriber A makes a call to subscriber B and the subscriber B has CRBT enabled. Also suppose that subscriber A and B are in different geographical location so that subscriber A calls are handled by MSC A and subscriber B is handled by MSC B. The figure illustrates the RBT call flow

Fig: Ring Back Tone Call Flow

Explanation:

 CRBT Architecture

Fig: CRBT System Architecture

Explanation:

This article explains the mobile network number system, its planning and coding

1. Network Parameters

1.1 Mobile Subscriber ISDN Number (MSISDN)

An MSISDN is the number that a calling dials to call a user in a digital PLMN cellular mobile communications network. The number format is as follows:

CC + NDC + SN

CC: country code, for example, 86 for China.

NDC: Mobile service access number, for example, 130 ~ 139 for China

SN: Comprise of HLR identification number(H0H1H2H3) and subscriber number in each HLR(ABCD).

1.2 International Mobile Subscriber Identity (IMSI)

The IMSI is the unique number used to identify a mobile subscriber in the digital PLMN. It is comprised 15 numbers. The number format is as follows:

MCC+MNC+MSIN

MCC: Mobile Country Code

MNC: Mobile Network Code

MSIN: Mobile subscriber identification number Here, MSIN contain H1H2H3H0?and the H1H2H3H0 is the same as H0H1H2H3 in the MSISDN. The IMSI is used in all signaling of the GSM mobile communications network and stored in the HLR, VLR, and SIM card.

1.3 Mobile Station Roaming Number (MSRN)

The MSRN is a temporary number allocated by the VLR, as required by the HLR, to a mobile subscriber being called to enable rerouting by the network. Once the connection is completed, this number is freed for use by another subscriber.

In the China Mobile network, its structure is 8613900M1M2M3ABC or 861374X M1M3M3ABC.

"M1M2M3" is the number of the MSC.

1.4 Handover Number (HON)

The HON is a temporary number allocated by the target MSC/VLR to a mobile subscriber to enable routing during an inter-office handover. As a part of an MSRN, this number can be used only when a mobile subscriber performs an inter-office handover. It can be freed for use by another subscriber once the connection is completed.

1.5 Location Area Identity

The LAI is used to identify location areas. Its number structure is MCC+MNC+LAC.

Herein, the MCC and MNC are the same as the MCC and MNC of the IMSI.

LAC (Location Area Code) uniquely identifies each location area in the digital PLMN in China. It is a two-byte hexadecimal BCD code expressed as L1L2L3L4 (in the range of 0000 ~ FFFF; it can define 65,536 different location areas).

1.6 MSC/VLR Number

The MSC/VLR number is used in the No.7 signaling information, representing a number of the MSC. The structure of an MSC/VLR number in the GSM mobile communications network in China is 8613900M1M2M3. Herein, the allocation scheme for M1M2 is the same as that for H1H2.

1.7 HLR Number

The HLR number is used in the No.7 signaling information, representing a number of the HLR. The structure of the HLR number in the GSM mobile communications network in China is an MSISDN with an all-zero subscriber number.

2. Coding Plan

2.1 E.164 Coding Format

MSISDN and other numbers are coded in the E.164 format, which is CC+NDC+SN. Mobile phone numbers, MSC, HLR, and other numbers are coded in the E.164 format.

2.2 E.212 Coding Format

The IMSI is coded in the E.212 format: MCC+MNC+MSIN.

2.3 E.214 Coding Format

The E.214 coding format is comprised of the CC and NDC in the E.164 coding format and the MSIN in the E.212 format. Its structure is as follows:

CC+NDC+MSIN

To understand how SMSC works, one needs to understand where it is located in PLMN. The figure below illustrates this:

Fig: Short Message Service Center (SMSC)

Where:

BSS:  Base Station Sub-System

MSC:  Mobile services Switching Center

VLR : Visitor Location Register

HLR : Home Location Register

OMC : Operation and Maintenance Center

SGSN:  Serving GPRS Support Note

GGSN:  Gateway GPRS Support Note

AUC : Authentication Centre

EIR:  Equipment Identification Register

PSPDN:  Public Switched Data Network

PLMN:  Public Land and Mobile Network

The SM-SC (Short Message Center) exists as an independent network element in PLMN, and occupies one signaling point in the SS7 network. In PLMN, it is connected to MSC, HLR, and SGSN via the SS7 network as shown in above picture.

The SMSC is mostly integrated with the IW/GMSC, that is, it has the functions of IW/GMSC to connect the SC with PLMN. Here, the GMSC receives short messages from the SMSC, requests routing information from the HLR, and forwards the short messages to the VMSC/SGSN of the mobile stations, while IWMSC receives short messages from PLMN and sends them to the receiving SMSC.

The functions of short message gateway are located inside the SC entity to connect PLMN via the standard MAP signaling

Architecture of single SMSC

A single SMSC usually consists of two major parts: SC and the External Short Message Entity (ESME). The former integrates both IW/GMSC and the short message service processing center with an internal interface in between. Between ESME and SC, the SMPP protocol interface is adopted. Standard SS7 links are employed for communications between the SC and the PLMN using a standard service interface in compliance with MAP protocol standards. The structure of the system is shown in the figure below:

Fig: SMSC Architecture

The SC comprises the service processing module, the Operation & Maintenance Module (OMM), the Billing Module (BM), SMPP agent module (SMEA module), junk short message monitoring module, and short message query module. Multi-level modularized design is adopted inside each of the modules. Short message entities (SMEs) are value added service platforms like the information station, manual station and automatic station.

Hardware Architecture

Fig: SMSC Hardware Architecture

The SC consists of the IW/GMSC, service processing module, OMM, BM, SMEA, junk short message monitoring module and short query module. Each module inside adopts multi-level modularized design. Various components are connected via the Fast Ethernet (FE) and communicate through TCP/IP. Dual networks are used to ensure the reliability of connections.

The functional structure of these modules is described briefly as follows:

1.    IW/GMSC module

Comprised of one or multiple modules to process the SS7 signaling, it is the interface between the SC and such functional entities as HLR/AUC, MSC/VLR and SGSN. The hardware is based on the ZXJ10 switching platform and the number of modules can be configured flexibly according to practical requirements.

2.    Service processing module

The service processing module is comprised of one or multiple service processing sub-modules in the mode of multi-module load sharing. Each module adopts the structure of dual-system server plus disk array as well as the Cluster technology to enhance the reliability of the system.

The service processing module is the short message service processing center. It is responsible for receiving the short messages submitted by SME and MS, storing and forwarding short messages, and attempting to forward again the short messages failed in forwarding. A high-performance industrial server is used. This module exchanges information with other network functional entities through the IW/GMSC.

The service processing module consists of the service processing server and the database system.

3.    Database module

To gain higher short message processing capability, the DB module can be separated from the service processing module so that an independent service DB module can be used to conduct operations such as storage and query of short messages.

4.    O&M module

The operation and maintenance module consists of OMM Server, and the Agent station and the maintenance station connected to the OMM server. The Agent station and the maintenance station provide the man-machine operation platform. Operators can find out the running state of the system, detect and remove faults via the maintenance console, and manage users via the Agent. In addition, the operator can also implement remote services handling, operation and maintenance via routers.

5.    SMPP Agent module

The SMPP Agent module provides the standard external SMPP protocol interface for the SC and implements the function of conversion between internal messages and standard messages. Each ESME accesses the SC just via this module.

6.    Charging module

The billing module is responsible for generating short message charging bills. For facilitating the charging settlement by operators, the SMSC system will generate three kinds of bills, that is, MO, MT and ACK bills.

The BM adopts Cluster technology and shared disk array mode, is connected to the SC via DDN/X.25 network, and complies with FTP/FTAM protocol.

7.    Junk SM monitoring module

The junk SM monitoring module is designed in client/server structure to separate its monitoring and management functions. The server monitors and collects the suspected short messages, while the client provides the function for the system administrator to query, analyze and handle the suspected short messages and suspected subscribers, thus implementing the centralized monitoring of multiple SCs.

The rack-mounted universal server is used as server of the junk SM monitoring module, which consists of the analysis agent module and the management server module.

8.    SM query module

The SM query module is designed in a client/server structure. The server receives the SMSC-originated short messages and sets up index information for them. Also, as the module to process query requests from the client, the server searches the short message index database for short message flags of calling and called subscribers and further for the detailed information of short messages.

The rack-mounted universal server and disk array equipment are used for the server of the SM query module.

Software Architecture of SMSC

Fig: SMSC Software Architecture

Functions of these modules are described as follows:

1.    Operation support module

The operation support module, located in the real time operating system, provides the development platform and the unified operation interface for the upper layer service so that the upper layer need not care about the specific structure of the lower layer hardware platform and the operating system.

2.    SS7 module

For receiving and transmitting SS7 signaling, the SS7 module (that is, the IW/GMSC part) exchanges information with the service processing module, supports OMM, and provides the SMSC system with the signaling transfer function.

3.    SMPP access module

The SMPP Agent module is responsible for the communication between the SC and ESMEs, converts SMPP standard messages into internal messages and vice versa, provides open interfaces for ESMEs to access the SC system, and provides TCP/IP based and X.25 based access modes.

4.    Database module

The database module in the IW/GMSC is for loading and accessing the system configuration information in the SMSC system.

The database module in the service processing module stores basic subscriber information, subscriber service information, short message information and SC configuration information in the system, providing the data management function and the loading of various configuration information.

The SMSC system adopts the memory database technology that greatly reduces the times of operating the physical database and immensely improves the processing capability of the system.

5.    Service processing module

The service processing module is the core component of the whole SMSC system. It is for MAP access processing, SMPP access processing, and short message service processing.

MAP access is used to exchange signaling between the SC and the GSM network, providing a short message receiving and transmitting channel for MSs.

SMPP access is used to connect ESMEs and SC, providing manual and auto stations with a channel for receiving and transmitting short messages.

Short message service processing refers to such functions as receiving, storing, forwarding short messages and repeated attempts to forward short messages.

6.    O&M module

The SMSC system provides such operation and maintenance functions as subscriber data management, short message data management, system configuration, system monitoring, authority management, fault management, diagnosis test, subscriber equipment tracing, signaling tracing, security management, file management, clock management, service observation, version management, operation log and performance statistics. It also provides an interface with the Operation and Maintenance Center (OMC) for the whole GSM network system.

7.    Junk SM monitoring module

To prevent some mobile subscribers from sending illegal advertising short messages and spreading retroactive information via the short message service system, the junk SM monitoring module monitors the frequency and keywords of mobile short messages. It provides the function of adding the suspected subscribers in the blacklist, so that they are restricted from sending short messages.

8.    SM query module

As a complement to the short message probe module, the SM query module provides new functions such as querying and deleting short messages according to calling subscribers and called subscribers, based on the original function of querying the destination subscriber information.

it leaves the target qubit t unchanged, when the control qubit c is
set to 0

|0>c |0>t --> |0>c |0>t , |0>c |1>t --> |0>c |1>t ,

and it causes a flip of the target qubit, when the control qubit is set to 1

|1>c |0>t --> |1>c |1>t , |1>c |1>t --> |1>c |0>t

To realize a controlled-NOT gate, one needs a physical mechanism that couples any target qubit to any control qubit. Cirac and Zoller (1995) found a suitable mechanism to be given by Coulomb repulsion, in their proposal of a quantum computer that is made up of cold ions stored in a linear Paul trap. This concept proved to be attractive for experimentalists. In fact, many of the techniques for preparing and manipulating quantum states of trapped ions have already been developed in the field of precision spectroscopy, and it has been shown that entanglement between two trapped ions was produced and quantum teleportation was realized in a three-ion system. Hence the trapped ion scheme is indeed prospective. So, to get a realistic idea of how a quantum computer might work, as a physical system, we can have a closer look at the Cirac–Zoller proposal. Dealing with ions, the two states of a qubit, |0> and |1>, are realized by two long lived energy levels.Working with alkaline earth ions, one may choose the state |0> as a sub-level of the S12 ground state, and the state |1> as a sub-level of the excited D52 state. Those two states are coupled through a quadrupole transition. So the excited state is metastable. Nevertheless, with the help of lasers optical transitions between the two states can be induced. A second important point is that by utilizing the quantum jump technique, level occupations can be reliably read out. With a properly tuned strong laser, resonance fluorescence can be excited exclusively between the ground state |0> and a suitable higher level, whereas no such possibility exists for the excited state |1>. So the occurrence of a fluorescence signal indicates that the qubit is in the state |0>, whereas the absence of such a signal tells us that the state |1> is occupied. In fact, this is the kind of measurement that enables one to read out the result of a computation.

Qa = $\begin{pmatrix} 3/4  & 0 \\ 0  & 1/4 \end{pmatrix}$ , Qb = $\begin{pmatrix} 9/10  & 0 \\ 0  & 1/10 \end{pmatrix}$ and Qc = $\begin{pmatrix} 1/2  & 1/4 \\ 1/4  & 1/2 \end{pmatrix}$

forms a convex cone. The composite system ingredients were varied to obtain set of entropic values.  For example, system A is in 10%, system B is in 40% and system C is in 50% of the mixture. The calculated values of entropies were plotted in Matlab and plotted in 3D to obtain 3D pictorial view of the allocation of entropies. This is shown below:

Another view:

Fig: Allocation of Entropy for Tripartite System

Another View:

Allocation of Entropies for Tri-Partite System as Convex Cone

]]> http://blog.ektel.com.np/2011/11/allocation-of-entropies-for-tri-partite-system/feed/ 0 http://blog.ektel.com.np/2011/11/allocation-of-entropy-for-bipartite-quantum-system/?utm_source=rss&utm_medium=rss&utm_campaign=allocation-of-entropy-for-bipartite-quantum-system http://blog.ektel.com.np/2011/11/allocation-of-entropy-for-bipartite-quantum-system/#comments Wed, 16 Nov 2011 12:59:00 +0000 admin and |+>]]> http://blog.ektel.com.np/?p=85 The allocation of Entropy of a Bipartite system has been proved to form a Convex cone. This can be found in the IEEE paper authored by Nicholas Pippenger. Here I am taking two bipartite system as:

1. Mixture of |0> and |1>

2. Mixture of |0> and |+>

In each case of the bipartite system case, the percentage of the two states are varied and entropy calculated. The entropies were then plotted in Matlab to obtain the following 3D view of the allocation of Entropy.

fig: Allocation of Entropy for Bipartite Quantum Systems

fig: allocation of Entropies of a two Bipartite System, the blue color plot is for the |0> and |+> mixed system, the green color plot is for |0> and |1> mixed system(click on the picture to enlarge)

The following plot is for the |0> and |+> mixed bipartite system:

fig: Allocation of Entropy for |0> and |+> bipartite system in 3D

Another view:

In this figure, the red part at the top is the area of maximum entropy for the bipartite system, while the blue at the bottom represents the minimum entropy of the composite system. Any two points inside the area satisfies the convex function criteria as well as the convex cone criteria. Hence the allocation of entropy is a Convex Cone.

Fig: 3D graph of allocation of Entropy for Bipartite System

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