Kronos OverviewKronos Overview

Pedro Parrilla

Prodys Support Department

Chapter goalsChapter goals Introduction. Description of the main features. Description of the component parts of the Kronos. Kronos Multiplexing: E1/T1 module. Kronos Management: Control module. IP traffic multiplexing. Audio Encoder Module. Audio Decoder Module. Synchronous data Module. E1/T1 link BackUp. Alarm system. Remote Control through TCP/IP with SNMP: ProdysControl. Practical example: Mpeg Layer III, 320 kbps audio distribution.

IntroductionIntroduction KRONOS E1/T1 Multiplexer is a system that allows transportation of voice channels, high

quality audio and data across 2.048 Mbps or 1544 Mbps structured links (E1 or T1 circuits), using time division multiplexing (TDM). It supports up to four E1 or T1 links with the possibility to drop/insert time slots across any of the connected E1 circuits.

In a E1 link, there are 32 time slots, 64kbps bandwidth each, which can be configured to convey data and/or audio information between Kronos.

Drop-Insert routes allow data/audio forwarding across E1/T1 circuits:

It is implemented using a modular construction on a common backplane architecture in 19” rack, being possible to cascade up to 4 racks. This all gives great flexibility in the choice of input and output modules to fit to the requirements of each application. These modules can be hot swapped for easy updating and servicing.

0 1 2 3 3031

E1-Rx

E2-Rx

E1-Tx

E2-Tx

E1/T1

Ec-Rx

Ed-Rx

E1/T1

Ea-Tx

Eb-Tx

Main FeaturesMain Features Ability to connect up to four E1/T1 circuits to one base device. Drop/insert across any of the connected E1/T1 circuits. AC or DC (48V) power supply. Option of redundant AC or DC power supply. Hot swapping of modules to make servicing and updating easier. Option to extend the configuration with additional racks (up to a maximum of 4 racks). Up to 24 full duplex audio channels per rack. Local or remote control and configuration through RS232 (Telnet) or LAN interface (SNMP). Ability to assign time-slots for IP traffic dynamically. Kronos routes LAN traffic through E1/T1

circuits. Totally configurable audio modules by software: selection of analog or digital interface as well as

encoding/decoding algorithm. A wide range of industry standard algorithms built in all the audio modules: G711, G722, apt-X standard and enhanced 16,20 & 24 bits, Mpeg Layer II/III.

Under 5 miliseconds end-to-end 20 Khz bandwidth coding at 192 Kbps. Audio source BackUp:If a threshold is not reached in an specified time, the audio source will be

switched: Analog to digital or vice versa. Bi-directional module of synchronous data (two ports per module). The interface can be

configured as V35 or X21 and as DTE or DCE. This system allows to establish a link as master and another one as slave. In that way, if a drop is

detected in the master link during a specified time, all the audio routes will be switched to the slave link. Up to 2 BackUp links can be configured.

Powerful alarm system. Alarms can be activated per module, and up to 7 GPO can be assigned to alarm events. A relay in the rear panel will warn of alarm events.

Kronos partsKronos parts Kronos frame: 19”-4U Rack mount. This is the main block where modules are

fitted. It can be cascaded up to 4 racks. Main power supply: It is always installed in the connector CN1 of the back

panel. The main power supply can be AC or DC. Secondary power supply: It is always installed in the connector CN2 of the

back panel. This power supply is optional and it is used as redundant in the case of failure of the main power supply. The secondary power supply can be AC or DC.

CONTROL module: This module looks after the configuration and monitoring of the system. It includes a GPO connector.

E1/T1 module: The Kronos allows two modules (up to four E1 or T1 links) they must be installed in the slots 0 and 1 of the rack.

Audio ENCODER module: This module carries out the audio encoding process and can be installed in any of the slots 2-14 of the rack. Each module can decode up to 2 independent mono audio signals. There are two types of Audio Encoder Modules: thin and normal modules. Thin modules have DB9 audio connectors and one rack can house up to 12. Normal modules contains XLR audio conectors and up to 6 of them can be housed in a rack.

CN1 CN2

Audio DECODER module: This module carries out the audio decoding process and can be installed in any of the slots 2-14 of the rack. Each module can decode up to 2 independent mono audio signals. There are two types of Audio Decoder Modules: thin and normal modules. Thin modules have DB9 audio connectors and one rack can house up to 12. Normal modules contains XLR audio connectors and up to 6 of them can be housed in a rack.

SYNCHRONOUS DATA module: It comes fitted with two V35/X21 ports which can be configured as DCE or DTE. This module can be installed in any of the slots 2-15 of the rack.

EXTENSION module: This module is needed to connect more than one frame. This module must be installed in the slot 15 of the main rack and in slots 0 and 15 of the secondary racks. It offers an option to extend the number of audio or data modules.

Module location constraints:Main Rack

MODULE Position in the rackMain power supply (AC o

DC)Connector CN1

Secondary power supply AC/DC

Connector CN2

E1/T1 module Slots 0 – 1

Audio Encoder Module Slots 2-14

Audio Decoder Module Slots 2-14

Data Module Slots 2-15

Control Module Slots 13 – 14

Expansion Module Slot 15

Secondary Racks

MODULE Position in the rack

Main power supply (AC o DC)

Connector CN1

Secondary power supply AC/DC

Connector CN2

Audio Encoder Module Slots 1..14

Audio Decoder Module Slots 1..14

Data Module Slots 1..14

Expansion Module Slot 0 & 15

Extension RacksExtension Racks There is an option to extend the number of audio or data modules

by connecting additional racks using the extension modules. Each of these racks has its own independent power supply, and the ability to also install a redundant power supply.

To extend racks, extension modules should be installed at the base and extension racks. The extension modules can be fitted on slots 15 and 0 of the backplane.

It is possible to install audio and data modules in the rest of the slots (1-14) of the backplane in the extended rack.

E1/T1 or control modules cannot be installed in the extension racks.

The way to interconnect the subracks will be as follows:

IP traffic through E1/T1IP traffic through E1/T1 Up to 20 time slots (1280 kbps) can be destined to IP traffic, which

will be multiplexed along with the time slots reserved for audio and data channels in the E1/T1 data flow.

This way, the control card is able to communicate by IP with remote units through E1/T1 channels, thus, being possible to access the whole network of KRONOS units for centralized management and configuration from an only one management application.

The control card is therefore a router that allows the interconnection of networks.

IP traffic

Kronos Management:Control ModuleKronos Management:Control Module

The control card has two connectors (CON & LAN) in order to allow two differents types of management: Console (local) and TCP/IP (remote) management.

Local management: The CON connector provides a serial port connection. It acts as DCE. The terminal that is connected to that port, must be configured at 9600 bps, No parity, 8 data bits, 1 stop bit, no flow control.

Remote management: The Control card has a TCP/IP stack, which allows the remote management through:

       TELNET service: Emulates the serial port console       SNMP service: Allows centralized management of

the unit with software, typically ProdysControl or HP Openview.

Management of local Kronos units (those connected to our LAN through the Kronos LAN connector) as well as of remote Kronos units can be carried out, since the Kronos routes the IP traffic through the E1/T1 links.

The Control card also provides with the following features: Control of the KRONOS clock: The Controller Card monitors the

state of the E1/T1 Line clocks and generates the Master clock for the KRONOS. If the line clock fails, the next active clock is assigned as Master clock.

Auto configuration of hot-plugged modules: When a card is inserted in to the Frame, the Control Card detects it automatically and configures the switching routes. In that way this card does not interfere with the current status of the unit. If the configuration is valid, it will start working immediately.

Auto configuration of the swapped cards: If a faulty module is replaced, the Control card detects the new one and the configuration is restored, the new card works to the same configuration as the faulty one.

Management of remote units: Kronos can route IP traffic through E1/T1 links, thus providing the ability to control remote units.

Audio Encoder ModuleAudio Encoder Module The audio encoder module allows the transmission

of audio signals through the E1/T1 circuits in different compression formats. User must select which channel(s) will be used to transmit the encoded audio. When selecting the encoding mode, only those channels with the required bandwidth for this mode will be available to choose from.

One encoded module can encode up to two different mono audio signals, and each encoded audio signals can be routed to different destination channels (distribution).

Algorithms: G711, G722, Mpeg Layer II/III, Apt-X, J41, J42, J57.

Selecting the audio source: Analog or digital. Gain adjustment: The gain of each channel can be

adjusted between +6 and –6 dB in steps of 1dB. Enabling the test tone: We can active or

deactivate a test tone of 1004 Hz and –12 dBFs in each channel. This tone will replace the input audio to all intents and purposes (vumeters, coding...), but will not be affected by the volume control.

It is possible to enable the audio source backup: If a threshold is not reached in a specified time, the input will be switched. Additionally an alarm can be activated to monitor whether the audio input

source has been switched.

Compression modes:Bandwidth and Compression modes:Bandwidth and total delay (encoder-decoder)total delay (encoder-decoder)

LayerII

LayerIII

Apt-X

Audio Decoder ModuleAudio Decoder Module The audio encoder module allows the reception

of audio signals through the E1/T1 circuits in different compression formats. User must select which channel (only 1) will be used to receive the decode audio. When selecting the decoding mode, only those channels with the required bandwidth for this mode will be available to choose from.

One decoder module can decode up to two different mono audio signals, with different compression modes or the same but different bit rate.

Algorithms: G711, G722, Mpeg Layer II/III, Apt-X, J41, J42, J57.

Selecting the audio ouput: Analog or digital (external, audio or internal synchronization).

Gain adjustment: The gain of each channel can be adjusted between +6 and –6 dB in steps of 1dB.

Enabling the test tone:The test tone of 1004 Hz and –12 dBFs can be activated or deactivated in each channel without being affected by the gain control. If the decoder is framed, its level will be reflected in the vumeters replacing the decoded audio.

Synchronous Data ModuleSynchronous Data ModuleThe Data module allows data transportation across the E1/T1 time slots.

The Data Card is able to manage up to two independent bi-directional lines of synchronous data, each one at a speed configurable between 64 kbps and 1984 kbps. The way these data lines are multiplexed across the E1/T1 time slots is totally configurable, allowing great flexibility in the assignment of available resources. The sum of speeds of the two data lines must not exceed 2048 kbps; otherwise only one of them will work.

The features of each one of these data lines are as follows:

V-35/X21 Interface with high-density connectors SCSI-20 (Micro-D). Working as DCE or DTE.

Bi-directional data line, with the same Tx and Rx speed.

Transparent synchronous data line.

Selectable speed of n x 64 kbps, from 64 kbps up to 1984 kbps, with option of deactivating the hand shaking lines (TD, CTS, DSR or DCD).

Reception from any E1/T1 channel.

Transmission/distribution to any E1/T1 channel.

Kronos Multiplexing:E1/T1 ModulesKronos Multiplexing:E1/T1 ModulesTwo main concepts to carry out Kronos multiplexing configuration: Channels: A channel is an unidirectional data flow (bits) at a bit rate

of N x 64 kbps, where N is less than 32. The user must define the channel before setting the route. One channel is defined by the E1/T1 link, the direction (Rx, Tx) and the number of taken time-slots.

Routes: A route defines the connection between input/output modules and channels. An Rx channel must be routed to an output module and a Tx channel must be routed to an input module. Bear in mind that data modules are bidirectional, so they can be both channel source and destination. There exists an special route called drop/insert route, which will connect an incoming channel to an outgoing channel, thus enabling data forwarding. The output channels will be no longer available. However, the input modules will be available for other routes. Note: You can define more than one route with the same origin and different destination channels, in other words distribution.

It is necessary to define the routes at each end of the E1/T1 link. Both ends of a route must have the same bandwidth (effective speed), link number and time slot allocation.

BackUp ConfigurationBackUp Configuration Kronos allows establishing a link as master and

another one as slave. In that way, if a drop is detected in the master link during a specified time, all the audio routes will be switched to the slave link.

Once the slave link is working, it will not switch to the master again until: A drop in the slave link happens during the

specified time for the master link. The Kronos is restarted. In that case, the

master link is established as active again. It is possible to define up to two independent

backup links. This way it is possible to handle up to four links.Timeout is the timer parameter to control when to switch to the backup link.

As soon as one link is selected as slave, user confirmation is required to delete all channels and routes. Since then, it is not possible to create channels or routes in this link.

Backup status: It is possible to monitor the backup status just placing the mouse pointer on the link module. A tooltip will appear with information on the backup status

ALARMS (1)ALARMS (1) Kronos allows to set up the following alarm events to be

monitored:

Link BackUp. IP traffic utilization at 100%. Error in offline configuration of Kronos. Error in offline configuration of module. Master clock changed. Line down. Encoder Audio BackUp. No input audio level detected. Route assigned but audio not framed. Voltage out of range. Error loading module. Communication with Kronos lost. Communication with module lost.

ALARMS (2)ALARMS (2) It is possible to select the rack

and the module involved in the alarm event to be monitored. When an alarm even from a module comes up, the module

background color changes, and the corresponding GPO when assigned is activated.

Remote control through Remote control through SNMP:ProdysControlSNMP:ProdysControl

ProdysControl is a suite of software tools designed to control and monitor several Prodys devices (Pronto1/2/3, ProntoNet, Kronos, etc…) from the same user interface. It consists of: Database:It stores all the required information for proper

operation. Server: This is responsible for communicating with devices and

registering them in the database. Client: It comunnicates both with the Server and the database.

It is the user interface which lets the user control several unit at once.

The communication protocol used in client/server communication is TCP/IP. The system functions on any LAN/MAN/WAN which supports TCP/IP.

Great flexibility: One or more ProdysControl Servers detect the units connected in a network and register them in a Database, and one or more ProdysControl Clients can communicate with the Database and the Server(s) to monitor and configure the Database registered devices.

ProdysControl: User InterfaceProdysControl: User Interface

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7

1: Menu 2: Toolbar 3: Device control 4:Device Catalog

5: Kronos window 6: States 7: Status Bar

Establishing an audio connectionEstablishing an audio connection Steps to carry out in order to achieve an MPEG layer III 320

kbps unidirectional (distribution) connection between two Kronos: Configure one 320 kbps channel at both ends. Establish a route: Click on a Encoder Module,select Mpeg Layer III, 320 kbps, and select thepreviously configured channel. Do the same in the RX Kronos, with the Decoder Module.