Overview of Telecom

Presented by : M. Mahdikhan Version 2015

Overview of Telecom

Presented By : M. MAHDIKHAN

Session 1

Panasonic communication systemsTraining Course


Cisco Press

Panasonic communication systems Manuals

VoIP Knowledge via Internet


1. Telecom History2. STANDARD COLOR CODE FOR TELECOM CABLE3. private branch exchange (PBX)4. PBX functions5. Interfaces for connecting extensions to a PBX 6. Interfaces for connecting PBXs to each other7. Interfaces for connecting PBXs to trunk lines 8. Interfaces for collecting data from the PBX9. Panasonic hybrid System – TE Series Configuration


History Of Telecom

Alexander Graham Bell (March 3, 1847 – August 2, 1922) was an eminent scientist, inventor, engineer and innovator who is credited with inventing the first practical telephone.


On October 9, 1876, Alexander Graham Bell and Thomas A. Watson talked by telephone to each other over a two-mile wire stretched between Cambridge and Boston. It was the first wire conversation ever held. on January 25, 1915 , the same two men talked by telephone to each other over a 3,400-mile wire between New York and San Francisco. Dr. Bell, the veteran inventor of the telephone, was in New York, and Mr. Watson, his former associate, was on the other side of the continent. They heard each other much more distinctly than they did in their first talk thirty-eight years ago.


Simple Circuit :


Switchboard Operators :


PSTN : Public Switch Telephone NetworkIt consists of telephone lines, fiber optic cables, microwave transmission links, cellular networks, communications satellites, and undersea telephone cables, all inter-connected by switching centers, thus allowing any telephone in the world to communicate with any other. Originally a network of fixed-line analog telephone systems, the PSTN is now almost entirely digital in its core and includes mobile as well as fixed telephones.


Telecom Infrastructure


Private Branch Exchange : PBXSystem components

• The PBX’s internal switching network.• Microcontroller or microcomputer for

arbitrary data processing, control and logic.• Logic cards, switching and control cards,

power cards and related devices that facilitate PBX operation.

• Stations or telephone sets, sometimes called lines.

• Outside Telco trunks that deliver signals to (and carry them from) the PBX.

• Console or switchboard allows the operator to control incoming calls.

• Uninterruptible power supply (UPS) consisting of sensors, power switches and batteries.

• Interconnecting wiring.• Cabinets, closets, vaults and other housings.

PBX

Telecom Company

http://en.wikipedia.org/wiki/Microcontroller

http://en.wikipedia.org/wiki/Microcomputer

http://en.wikipedia.org/wiki/Uninterruptible_power_supply

http://en.wikipedia.org/wiki/Battery_(electricity)


Extension :

Analogue HybridDigitalDECTIPSIP


CO/TRUNK:

Analogue / CO Digital : E1/PRI IP-GW SIP-GW


A way is required to turn analog phone signals into digital signals that can be sent over the Internet.

VoIP/Digital


Supervisory Signaling

On-hook Signal Off-hook Signal Ringing


Information Signaling

Dial tone Busy Ringback Reorder


Address Signaling

DTMF (Dual-tone Multi-Frequency) Pulse


PulsePulse Mode works in rotary dialing phone. It works in this way. When you rotate to a number, then pulse will be sent to the central. I’ll illustrate that like this. When you rotate to “1″, then only 1 pulse will be sent to the central. If you rotate to “9″, then 9 pulses will be sent to the central.Each pulse consist of high and low. High means 33 ms. Low means 67 ms. The spare time between the number that you rotate will cost 400 ms.1 means 100 ms ; based on this : 33 ms + 67 ms.8 means 800 ms ; based on this : 8*(33+67) ms.0 means 1000 ms ; based on this : 10*(33+67) ms


DTMF

The second system is DTMF. In this system, when you push a button, then there’ll be 2 frequencies sent to the central. If you push 3, then 657 hz and 1477 hz will be sent to the central.


E.164 E.164 is an ITU-T recommendation that defines the international public telecommunication numbering plan used in the PSTN and some other data networks. It also defines the format of telephone numbers. E.164 numbers can have a maximum of fifteen digits and are usually written with a + prefix. To actually dial such numbers from a normal fixed line phone, the appropriate international call prefix must be used.

Country Code National Destination Code (optional) Subscriber Number

National (significant) number

cc = 1 to 3 digits maximum = 15 − cc = 12 to 14 digits

International public telecommunication number for geographic areas (maximum 15 digits)


PSTN Managednetwork

Wireless

PublicInternet

Managednetwork

Today Technology ….


PSTN Advantages and Disadvantages

Advantages

Well established technologyEasy maintenanceHassle free set-up processSimplicity in usage procedures

Disadvantages

Dedicated line required to complete a callLimited scalabilityOptimum usage of bandwidth not possibleMonthly fees applicable for maintenanceHigher call charges


TWO Solution :Digital E1 PRI

VoIP LAN WAN


E1/PRI30


An emerging set of applications or protocols that allows you to make telephone calls over the internet.

The Internet

Voice VoiceVoIP


A way is required to turn analog phone signals into digital signals that can be sent over the Internet.

VoIP/Digital


VoIP makes use of Media Gateways and Media Gateway Controllers

Three different types of VoIP services:

• Analog Telephone Adaptors• IP Phones• Computer-to-Computer

Requirements:

• Broadband Internet Connection• VoIP subscriber’s account• Wi-Fi enabled phone

(if you want to make use of mobility)

VoIP/Digital


User Services :


User Services :

Call forwarding and overflow Call forwarding and call overflow reroute calls

intended for one set to a different set:Forwarding: the user activates the forwarding

and chooses the destination set to which incoming calls are rerouted

Overflow: the user cannot activate overflows. Overflows are activated in system management


User Services :

Call pick-up Call pick-up enables a user to answer an

incoming call to another set on his own set.


User Services :

Camp-on The camp on feature allows a user to

automatically or manually camp on the set of another user already engaged in a call.


Automatic off-hook dialing (hotline)Automatic off-hook dialing enables a set to

directly call a predefined number when picked up.

User Services :


User Services :

Business account callsThe cost of a call can be charged to a specific

business account (project), configured by the system administrator.


User Services :

Call park Parking a call means that an internal or external

caller can be put on hold on a set and this call can be picked up from any other set (retrieving the call).


User Services :

Callback requestA callback asks the calling to call back.Reserve line


User Services :

Hunt groups A hunt group enables sets to be grouped together

under a single call number.Parallel UCDPriority Hunt


User Services :

Direct Inward System Access (DISA)


User Services :

Direct Inward System Access (DISA) Automated Attendant Call an extension by dialing the extension number. Call another outside party via the outside (CO)

lines of the PBX. Access the desired extension simply by dialing a

single-digit number (DISA Automated Attendant [AA] number) using DISA AA service.


Questions?

Thank you

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Panasonic PBX Expert Group

Overview of Telecom

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