Documentation

Revision as of 16:13, 8 November 2012

Here are a few links you can start from. In addition, you might want to take a look at the list of all categories or all pages.

x164 Introduction

x164 consists of a central database which holds private and public rate tables, statistics and route configurations. Many x164 switches connect to the central x164 database to retrieve routing information and to update the statistics in realtime. Softswitches are preferably, but not limited to, yate-based switches. Call detail records are collected with radius. Call details, statistics and the configuration screens are accessible by the web access.

Rates database

x164 system relies on the rates database to perform different tasks: authenticating users, looking up routes, setting up credit limits and blocking bad routes among others. Ip addresses for switches are set in the Gateways table. Carriers and Customers are defined separately in their own tables, and are linked to a profile in Profiles, which in turn is attached to a set of rates in the Rates table. A profile can be of type 'IN' (links customers to incoming rates), 'CARRIER' (links carriers to outgoing rates ), or 'DIDRANGE' (routes that terminate in your own network). DID numbers are defined in DIDcients. The table relationship is as follows:

It is possible to allow the user to choose dynamically between different rate sets by using prefix dialing. This is accomplished by creating many instances of the same incoming profile and setting a different rate name and prefix for each one of them. Rates associated with this profiles will only be available when dialing the prefix.

Currencies sets the exchange rate to euros for each currency. When looking up routes, the field 'curr_code' in Profiles links to the matching exchange rate and the price for routes is normalized according to it.

Finally, monthly credit limits for subscribers can be set in the Quota table. This table keeps record of the monthly bill sum for each subscriber. Ia quata is set and the limit is reached, the subscriber is blocked. This means the field 'blocked' of its entry in the Customers or Carriers table is set to 1. Unblocking must be done manually.

x164 Call flow

When receiving a call, the softswitch queries the database for user authentication. The flag 'Dynamic_IP' in Customers indicates if the customer uses fixed or dynamic IP. In the first case, authentication is made by IP. In the second, the fields 'Subscriber' and 'Password' are used. If the authentication is positive, the system checks that the user is linked to an incoming rate for the dialed number: the field 'Profile' links to a record in the Profiles table, and the field 'Rate' of this record links to a set of rates in the 'Rates' table that define the destinations that the user is allowed to call, and the rate charged for each one. If there is a match between the called number and one of this rates, the softswitch looks up the database for outgoing rates.

Outgoing rates are retrieved in the same way, but this time the path is Carriers -> Profiles -> Rates. This time a set of rates is retrieved for each available carrier. The algorithm takes the longest match for each company and measures the expected profit taking in account the incoming rate, the outgoing rate and the route's quality statistics available in the Rates table. If no matched rate is profitable, the call is blocked. Otherwise, the most profitable rate is picked and the call is routed. At the end of the call the CDR database and the route's statistics are updated.

Web Access

x164 provides its members a web access to configure their settings, upload their rate tables and view call statistics. The interface and rating-engine is derived from CDRTool, which we modified heavily for speed and simplification.

Call search menu

Description

The call search offers access to call-detail-records (CDRs). CDRs can be summarized and filtered for various statistics.

Selection fields

Rating menu

Access to all data influencing the rating and routing. The rating data is contained in several tables which can be selected on the top-right side. The cost calculation of the calls stored in the system occurs in parallel and periodically using the values that the user introduce ​​in this tables.

Customers table

Description

The Customers table shows details of your authorized customers who may send calls through the x164 system. The user can be authorized by trusted peer or subscriber and password.

Data fields

Carriers table

Description

The Carriers table has the details of your carriers to send calls to them.

Data fields

Profiles table

Description

The profiles table shows the rate details assigned to customers which will be used to calculate the price of the call by x164 system,

Data fields

Rates table

Description

The rate table shows details to calculate the price by x164 system according to valid tariff and destination

Data fields

Gateways table

Description

The gateways table serves to identify the IP address of the switches used by the reseller.

Data fields

DIDclients table

Description

The DIDclients table shows the DID clients with their numbers.

Data fields

Currencies table

Description

The currencies table shows the currencies used by x164 system. They are used in the routing process to look for the most appropriate route.

Data fields

Quota table

Description

The quota table stores the billed sum of calls made by each subscriber. The table allows to set a monthly quota limit. When the limit is reached the subscriber is blocked. The usage is reset at the beginning of each month. Un-blocking of subscribers has to be done manually.

Data fields

Generation of client rate tables

x164 allows to generate rate tables for customers from outgoing carrier rate tables. x164 consolidates the carrier rates into one rate table following a strict longest-code-match logic. The rate table can be further simplified by filtering for quality or consolidating prices within tolerances to one code/price.

The operation takes the following parameters as inputs:

First rates are retrieved filtering by date and reseller id. The reseller id is found in the Gateways table using the secret_key parameter. The relationship with the Rates table is defined as folows:

After this initial filtering the system searches for the best prices. For each destination code, the longest match per carrier is retrieved. Then the qACD and qASR parameters are taken in account. If any of the matches satisfies this limits, the cheapest route is selected. If the cheapest price is common to many routes, the one with the highest quality is picked. When none of the longest matches per company satisfies the quality limits, the process is the opposite: take the route with the highest quality firs, and if there is more than one choose the cheapest of them.

At the end of this process there will be one record for each destination dialing code. Before starting with the simplification stage, all records with price lesser than rateMin are set to rateMin.

In the next steps, rates will be simplified using the tolerance parameter. First, redundant codes will be removed if shorter codes exist within their price tolerance. As an example, consider the following record:

Destination	Price
371660		25

With a tolerance of 15%, this code would be deleted from the final selling table if a shorter match with price within the range [22.5 - 28.5] is found, such as:

Destination	Price
3716		26

In the second part of the simplification process, the algorithm groups sets of ten consecutive codes, like the following:

Destination	Price
3710		50
3711		50
3712		45
3713		51
3714		47
3715		48
3716		49
3717		50
3718		47
3719		46

First the system makes sure the shorter code (371) does not already exist in the database. If it doesn't, it checks that all the prices are within the tolerance range. In the previous table case, for a tolerance of 15%, the cheapest price upper limit would be 45*(1+15/100) = 51.75, which is superior to the highest price in the set. Thus, this set is removed from the final table and a new record is created, using the information of the most expensive code, and updating the destination field to the one that comprehends the whole set:

Destination	Price
371		51

Once the simplification process is over, codes longer than max_code_length are deleted. Finally, all the prices are increased according to the profit percentage specified in the input.

CSV import and export

The x164 system supports CSV import and export to ease the task of updating the rating tables. CSV files are plain text files which store spreadsheet or database information, using commas to separate fields and line breaks to separate records. Rating related information will frequently be available in some spreadsheet format, so in order to upload it to the x164 database you will need to export to CSV first.

"Destination", "Price"		// Example of CSV file with two fields ('Destination' and 'Price')
34928, 120			// and two records.
349287, 100

Export a spreadsheet file to CSV

We will be using OpenOffice Calc for this example, although the process is similar in other spreadsheet softwares like Excel. First step is to reorder your data to fit the x164 format. Take as an example the following rates table with two records:

Country			Country Dial		$ USD		Effective Date
Spain			34			0.258		Oct 09, 2012
Spain			34928			0.1757		Oct 09, 2012

Create a new spreadsheet where the first row contains the field names for the relevant x164 table, in this case Rates. The only exception is that the first field 'Id', that instead must be named 'ops' and set to '1' for every row. Then insert your data in the appropiate fields of the new spreadsheet:

ops	Reseller   Rate		Destination   Region	Description	App	Conn	Price	Conn In	Price In  Start Date  End Date
1	100	   Rate_Name	34			Spain		Audio		2580			  09-10-2012
1	100	   Rate_Name	34928			Spain		Audio		1757			  09-10-2012

Note that CSV files use line breaks to separate records and commas to delimit fields. You must ensure those are not present in your data.

To export the spreadsheet to a CSV file in OpenOffice, simply go to File -> Save As and select "Text CSV (.csv)". In the opened dialog you must rename the file with the name of the destination table, an underscore '_' and a number.

rates_1.csv		// CSV file names example for the Rates, Carriers and Profiles tables.
carriers_25.csv
profiles_81.csv

Import a CSV file to the database

In the x164 web access, go to the destination table and click on 'Choose a file'. Select your file and click 'Import'. When the file is correctly uploaded a confirming message will be prompted. The imported data will be available after a few minutes.

Export table as CSV file

You can also export data from the database in CSV format by clicking on the 'Export table.csv' button on the right side of a table. A new browser window will be opened showing the CSV text.

Softswitch

The x164 switch is based on yate, In its basic configuration the switch can handle SIP and H323 calls. IAX, ISDN, SS7 calls are theoretically possible. Users can activate further yate modules to extend the possibilities. x164 members are encouraged to post their suggestions and ideas on the forum. The yate configuration is located in /usr/local/etc/yate.

Server settings

Time zone

The server running yate should have its timezone set to GMT time if the timezone setting is used in the rating customers table. The timezone setting in the rating customer table must reflect the local time of the tariff in the rating profile table. The timezone setting is used to correct the CDR timestamps coming from the softswitch. The Starthourweek and Endhourweek time ranges in the rating profiles table are always in local time.

CDR module - cdrbuild.conf

Description

This module builds the CDR messages (Call Details Record) which are used later in the radius module. Here are set the necessary attributes to create the correct CDR messages.

h323 Channel module - h323chan.conf

Description

This module gives support to h323 protocol by using the open h323 library.

Mysql database module - mysqldb.conf

Description

This module is used to make the connection between yate and a MySQL database. Establishing the necessary parameters as host, port, database and password.

Radius module - yradius.conf

Description

This module give support to establish communication between Yate and FreeRADIUS, as well the ip address and port of the FreeRADIUS server. Are set the specific attributes to sent in the CDR message and are assigned the correct values.

Regexroute module - regexroute.conf

description

This module is used in addition to the register module, to assign values ​​of different parameters in the call as the error messages or the formats to use in transcoding calls, used to route calls without using database.

Register module - register.conf

The register module defines the messsage handlers which are communicating with the x164 database. Message handlers "catch" internal yate messages, issue queries to the database and return the result back to yate. x164 is configured to use mysql stored-procedures as message handlers.

Authuser

Description

User_Auth is used to identify the subscriber.

Statement

PROCEDURE `proc_user_auth`( 
IN username VARCHAR(100),   // username received in SIP INVITE
IN domain VARCHAR(100),     // domain name from caller
IN address VARCHAR(25)      // IP address and port of the received call
IN password VARCHAR(25)     // secret key for MySQL procedures in Yate
)

Register

Description

This query handle register messages, add in database data of register users and the last time that the user was registered.

Statement

PROCEDURE `proc_user_register`( 
IN ip_host VARCHAR(30),		// IP address received in SIP INVITE
IN ip_port INT,			// IP port received in SIP INVITE
IN expires INT,			// register expiration time
IN authname VARCHAR(125)	// authorized subscriber name corresponding in data base
IN password VARCHAR(25)		// secret key for MySQL procedures in Yate
)

Unregister

Description

This query handle unregister messages initializing the data entered by register message.

Statement

PROCEDURE `proc_user_unregister`(
IN authname VARCHAR(125)        // authorized subscriber name corresponding in data base
IN password VARCHAR(25)        // secret key for MySQL procedures in Yate
)

Engine timer

Description

The engine timer found that users have exceeded the time of registration and invalidate the dynamic_ip.

Statement

PROCEDURE `proc_user_enginer_timer`(
IN password VARCHAR(25)       // secret key for MySQL procedures in Yate
)

Preroute

Description

Preroute checks whether an incoming route for the combination of IP address and called number or authname and called number exists. The caller is either identified by IP address or was identified by authname/password combination in authname procedure. If no incoming route exists the call is blocked.

Statement

PROCEDURE `proc_get_preroute`( 
IN authname VARCHAR(125),     // authorized subscriber name corresponding in data base
IN address VARCHAR(25),       // IP address and port received in SIP INVITE
IN called VARCHAR(100)        // the called number, optionally with prefix
IN password VARCHAR(25)       // secret key for MySQL procedures in Yate
)

Route

Description

This selects the possible outgoing routes according to the incoming parameters, looking for the best quality and profit. Unprofitable routes are blocked.

Statement

PROCEDURE `proc_get_route`( 
IN usernameNobuy VARCHAR(125), // Subscriber_out found in incoming route to prevent call loops
IN rtproxy_in TINYINT(4),      // 0/1 flag to specify whether the rtp stream of the incoming call leg is proxied.
IN realRateSell FLOAT,         // (client) call rate found in preroute expressed in the base currency (EUR) 
IN called VARCHAR(100),        // Called number (optionally with prefix). The prefix is not used.
IN _format_in VARCHAR(255),    // Codecs received in incoming call leg
IN password VARCHAR(25)        // secret key for MySQL procedures in Yate
)

Route V2

Description

Selects the possible outgoing routes according to the incoming parameters. It also allows to select the routing method, set quality limits, and enable loss making calls.

Statement

PROCEDURE `proc_get_route_v2`( 
IN usernameNobuy VARCHAR(125),		// Subscriber_out found in incoming route to prevent call loops
IN rtproxy_in TINYINT(4),		// 0/1 flag to specify whether the rtp stream of the incoming call leg is proxied.
IN realRateSell FLOAT,			// (client) call rate found in preroute expressed in the base currency (EUR) 
IN called VARCHAR(100),			// Called number (optionally with prefix). The prefix is not used.
IN _format_in VARCHAR(255),		// Codecs received in incoming call leg
IN password VARCHAR(25),		// secret key for MySQL procedures in Yate
IN routing VARCHAR(100),		// Routing method: 'least_cost', 'quality'. Default is profit routing.
IN qACD INT,				// Minimum Average Call Duration. Routes below this limit are blocked.
IN qASR INT,				// Minimum Success Rate (successful calls/total calls). Routes below this limit are blocked. 
IN blocklosscalls TINYINT(4))		// 0/1 flag, blocks unprofitable calls when 0
)

cdr_finalize

Description

This procedure computes the values ​​of the call once finished to update the statistics in the system.

Statement

PROCEDURE `proc_cdr_finalize`( 
IN duration FLOAT,         // the overall call duration
IN billtime FLOAT,         // the time the call was connected
IN ringtime FLOAT,         // duration of call ringing
IN direction VARCHAR(10),  // incoming or outgoing
IN status VARCHAR(10),     // if the call was connected or not
IN rateidBuy BIGINT(20),   // id of the rate for the outgoing call leg
IN rateidSell BIGINT(20),  // id of the rate for the incoming call leg
IN password VARCHAR(25)    // secret key for MySQL procedures in Yate
)

RTP Channel module - yrtpchan.conf

Description

This module provides RTP and udptl transports for any technology that requieres it as SIP or H.323. The RTCP support is disabled.

SIP Channel module - ysipchan.conf

Description

This module give support to SIP protocol using the YASS library. Here also is posible select the value "expires" used in register.conf and the codecs enable to use.

Yate - yate.conf

Description

In this configuration file is selected the modules that are in use, and the parameter "timeout" limits the call duration as 2h.