One of the most important network elements in the mobile telecommunication services is Intelligent Network (IN). IN connected telecommunication services providers and customer needs in order to all services can run well. The main function of IN is related to the billing function that will be implemented to the customers during accessing the services. Customer request will be accepted or not depend on the status of the numbers they have, if the number is valid (active state and have enough balance) then it will be allowed to access the service and if the number is invalid (expired state and low balance or expired state but enough balance) then the service will be blocked
All services application will connected directly or through interfacing to IN to do billing process. In the CDMA network those application included voice and SMS services and Value Added Services (VAS), e.g. download contain services, WAP application, CDMA 1x service etc. Since IN has the most important function in the mobile telecommunication services then generally they built in multi redundancy and have high capacity occupancy. These are reasonable to make sure that all services will run well and services will be not interrupted if one of IN failed to served. Moreover, this deployment to make sure those services will still have good performance to carry out much traffic
CDMA 1x and Value Added Services as the one of the services that need IN availability continuously are sending request every time whenever subscribers activate the service. The huge requests are possible to be sent from one application service (more then a thousand request per second). Image if the mobile telecommunication providers have fifty millions subscribers and there are five services they provided. The IN availability become the main issue for such provider. They must provided many IN system in their network and fully redundant, otherwise the services will always interrupt once high traffic come. As the result their subscribers will leave them. Generally CDMA 1x and VAS services both have the same charging system or in the some case, sometimes VAS have separate billing system that built indeed. In the case they have the same one, the charging system will need to connect to IN directly or in many case IN provide the gateway to connect their SCPs. Others services that need to have IN services used to attach to this gateway.
What will happen once subscriber activates the service? Commonly there are two type of subscriber billing status; they are prepaid and postpaid subscribers. IN will serve to the prepaid subscribers only meanwhile postpaid will only write in each billing application services and will be report to the postpaid billing application.
Following are the process will be done by SCP once the request coming in the CDMA 1x and VAS services;
1.Application billing system will send balance query request to IN
Once the session is coming the first thing that will be done by application services is sending request to the SCP according to the subscriber status.
2.SCP will look into the subscriber profile
If subscriber is valid (active state and enough balance) then it will be allowed to access the traffic, otherwise it will be blocked. This checking also will look forward what kind of service (class of service, COS) they have in the database. If the profile it matched then those services will be applied to this subscriber and vice versa
3.SCP will response the request
If request from application service is matched SCP will send response to identify that subscriber is valid and allow to access to the service
4.Application billing system will deduct amount of balance
Once request is responded then amount of balance will be deducted as the charging for the service
5.Application service will allow the traffic
Subscriber then will be allowed to access the traffic for that much balance they deducted. Once subscribers need more traffic, the same process will happen until subscriber terminate the session, disconnect the service
Due to huge request sent to IN, sometimes IN failed to handle the service. The error message will be sent by IN to application services to indicate what kind of errors it is. Some of application services forward these errors to subscriber to notify why they failed to access the service and some of them keep these errors in their system
Thursday, August 6, 2009
Billing status codes
Tuesday, June 9, 2009
why my internet connection fail?
There are many reason subscribers will get failure during access CDMA 1x through the Laptop/PC or handsets. The reason could be from subscribers end or network providers. Which side is having problem during accessing can be identified from the display errors that sent to subscribers. Errors mentioned below are common occurred at CDMA 1x but it is possible that the same errors occurred in the others network platform e.g. GSM, 3G and WCDMA networks
Here are data session processes starting from subscribers until they get internet service. Generally these processes are done by subscribers using Laptop/PC
1. Subscribers preparing their device by connecting the modem device to the Laptop/PC
Subscribers need to make sure that there are no issue connections in their device before data call dialing. It can be done by query the modem attached to the laptop/PC. Once query received succeed messages, it means the device ready to make a session
2. Data call then will request RF channel to the BTS. Once the channel is available then it will be occupied for active subscriber’s session.
Channel will be occupied as long as subscriber is active status. It means once subscribers leave the Laptop/PC and do nothing for a few time until reach dormant time then the session will be terminated
3. BSC will send IP channel to PDSN network
MSC will identify what kind of request send by subscribers. If it data call request then forward it to PDSN to reserve IP channel. MSC identified the called number sent by subscribers and if it is specific number (in this case #777 is a data call request) then MSC will send it to PDSN. At the same time, MSC will identify the subscriber number whether it is authorized to get data cal in the HLR. If the subscriber profile is available in the HLR then he/she will allowed to access it
4. PDSN will process the request and send the traffic once the parameters required is complete
There are many process will be executed by PDSN as the core device to serve data call.
They are:
- Allocating IP Pool: subscribers will be reserved one IP Pool to this session
- Sending authentication request: Authentication server will identify if the subscriber is a valid session. If yes then will be allowed to go to the next step
- Sending accounting request: this is the next step after authentication step is passed. Accounting server will check whether subscriber have enough balance or not. If balance is enough then will be permitted to access the internet service or another services provided by network provider. If not enough then the session will be blocked
- Forwarding internet traffic to customer through BSC's PCF
Below are errors message will be received by subscribers once they got unsuccessfully data call session;
1.Invalid username and password (error 691)
This error due to some reason below:
a. Subscriber put the wrong username and password.
b. Subscriber’s dialer has gone corrupt
How to get this error to go away:
1) Check the username and password.
2) Check which number the dialer is dialing, it should be #777.
3) Recreate the dialer.
Steps to recreate dialer:
a) Go to ‘Start’ >> ‘Control Panel’ >> ‘Network Connections’ >> on the left hand side you have the option ‘Create a New Connection’.
b) Follow the steps as: click on ‘Next’ >> ‘Connect to Internet’ >> ‘Setup Connection Manually’ >> ‘Connect Using Dialup Modem’ >> then enter username and password >> click ‘Finish’.
2.Hardware (modem) problem (error 797)
This error is coming due to modem was installed improperly. How to make sure the modem was installed proper or no?
a)Go to ‘Start’ >> ‘Control Panel’ >> phone and modem option >> click modem >> properties >> diagnostic >> query modem
b)Once this query is getting succeed response message, it means the modem is ready to be used
3.The remote computer did not respond (error 721)
This is error due to many reasons;
a.Session is not getting RF channel from the BTS
b.The number used by subscriber is not registered in the HLR to have data service feature. HLR is checking that the number is not available to have data service feature
c.The session is rejected by HLR
How to get this error to go away?
If this is caused by RF capacity what we can do is trying to connect in the low traffic time. But if this is caused by HLR customer need to contact the provider the check the number
