What is VoIP?

transcript

What is VoIP?

VoIP (Voice over Internet Protocol), sometimes referred to as Internet telephony, is a method of digitizing voice, encapsulating the digitized voice into packets and transmitting those packets over a packet switched IP network.

Why VoIP? (Key Benefits of VoIP)

• Elimination of expensive leased lines, PBXs and PBX lines and PSTN lines with recurring monthly costs

• Ease of adds, moves and changes.

• Elimination of costly tie lines between multiple PBXs

• Reduction of supported PBXs resulting in the reduction of annual maintenance and support contracts

• Reduction of costly long distance charges between branch offices via toll-bypass – sending voice traffic over the existing data network

VoIP Voice Protocols

VoIP uses two common protocols to carry your voice:

– User Datagram Protocol (UDP)

– Real-Time Protocol (RTP)

RTP DataIP UDP

VoIP Packet

Voice over UDP

• UDP was not designed for transporting voice

• Due to its quick transporting ability, it is suitable for voice

• Basic shortcoming of UDP

No packet loss recovery mechanism

• Voice communications can tolerate some loss

• Efficient coding techniques can be design

to recover some lost packets

• Supporting QoS can reduce the probability of packet loss

No packet ordering scheme

Packets in the same session are unlikely to follow different paths

…we still like to resolve some of the shortcomings of UDP

Real-Time Transport Protocol

• Provides end-to-end network functions and delivery services for delay-sensitive, real-time data, such as voice and video

• Works with queuing to prioritize voice traffic over other traffic

• Services include:

Payload type identification

Sequence numbering

Timestamping

Delivery monitoring

VOIP Signaling Protocols• H.323 -

ITU standard, ISDN-based, distributed topology - 90%+ of all Service Provider VoIP networks - The current interconnect for CallManager to Service Providers - Useful for video applications

• SCCP (Skinny Protocol)- Centralized Call-Control architecture. - CallManager controls all features.- over 700,000 IP Phones deployed

• MGCP - IETF RFC2705 - Centralized Call-Control Architecture - Call-Agents (MGC) & Gateways (MG)

• SIP - IETF RFC2543- Distributed Call-Control - Used for more than VoIP…SIMPLE: Instant Messaging /

Presence

VOIP Signaling Protocols

H.323 between Cisco CME systems

PSTN Gateway and IP to IP

Gateway functionality

VOIP Topology that will be created in lab.

Analog Phones

ATA 186

401301 302

201 202

1751 Router with CCME

101 102

27575432

55575432

Cisco IP Phone 7905

Cisco IP Phone 7960

Cisco ATA 186

Panasonic PBX 3/8

Voice Dial Plans, Configuring Voice Interfaces and Dial Peers

Cisco Networking Academy Program

Analog Voice Interface: FXS

• Connects directly to analog phones or faxes

• Used to provision local service

• Provides power, call progress tones, and dial tone

Foreign exchange station interface

Analog Voice Interface: FXO

PSTNFXO FXO

• Connects directly to office equipment

• Used to make and receive calls from the PSTN

• Can be used to connect through the PSTN to another site

• Answer inbound calls arriving

Foreign exchange office interface

Dial-Peer Call Legs

Configuring Dial Peers

Understanding Dial Peers

• Cisco voice-enabled routers support two types of dial peers:

POTS dial peers: Connect to a traditional telephony network

VoIP dial peers: Connect over a packet network 2600XM

Configuring POTS Dial Peers

Configuring VoIP Dial Peers

Default Dial Peer 0

PLAR Connection

Configuring Cisco CallManager Express (CME)

Cisco Networking Academy Program

Overview of Cisco CME

What is Cisco CallManager Express?

Cisco CME

Trunks

• Call processing for small to medium sized deployments

• VoIP integrated solution

• Up to 120 IP phones

• IOS based solution

Cisco CallManager Express Requirements

• Select IOS based platform

• Multiservice access routers

2600XM

• IOS platform

12.3(7)T or greater is recommended

IP Voice

• Cisco CME software and files

GUI files

Firmware

Cisco CME Features and Functionality

Supported Protocols and Integration Options (Cont.)

Analog Phones

ATA Skinny

Skinny

Analog

H.323 Or SIP

FAX ATA

Supported Protocols and Integration Options

(1) H.323 Protocol

(2) Session Initiation Protocol (SIP)

(3) Skinny Client Control Protocol (SCCP)

• Cisco proprietary

• Call Control protocol

• Lightweight protocol

• Low memory requirements

• Low complexity

• Low CPU requirements

Supported Protocols and Integration Options (Cont.)

• Cisco CME does not support remotely registered phones

Remote PhonesLocal Phones

DHCP Service Setup

• Assigns an IP addresses and subnet masks for one or more subnets

• Optionally can assign a default gateway

• Optionally can assign DNS servers

• Optionally can assign other commonly used servers

• The DHCP scope can be customized to assign a TFTP server to IP phones

• Best practice is to configure a DHCP scope for the IP phones

Dynamic Host Configuration Protocol

DHCP Service Setup (Cont.): Phone Bootup

• Range of available IP addresses

• The subnet mask

• A default gateway

• The address of the TFTP server

• DNS server(s)

On the Cisco CME router a DHCP Scope can be configured. The scope should define the following:

The IP phone powers on

The phone performs a Power on Self Test (POST)

The phone initializes the IP stack

The phone boots up

Continued next slide…

DHCP Service Setup (Cont.): Phone Bootup (Cont.)

IP phone send DHCP Discover broadcast requesting an IP address

DHCP server selects a free IP address from the pool and sends

along with the other scope parameters as a DHCP Offer

The IP phone initializes applies the IP configuration to the IP stack

The IP phone requests it configuration file from

the TFTP server

DHCP Service Setup (Cont.)

Configuring DHCP on an IOS router

• Option 150 sets the TFTP server on the IP phone

• The TFTP server contains the configuration files and firmware for the IP phone

CMERouter(config)#ip dhcp exluded-address 10.90.0.1 10.90.0.10CMERouter(config)#ip dhcp pool mypoolCMERouter(dhcp-config)#network 10.90.0.0 255.255.255.0CMERouter(dhcp-config)#option 150 ip 10.90.0.1 CMERouter(dhcp-config)#default-router 10.90.0.1CMERouter(dhcp-config)#dns-server 10.100.0.1 10.100.0.2CMERouter(dhcp-config)#exit

IP Phone Registration

• Firmware

• SEPAAAABBBBCCCC.cnf.xml

• XmlDefault.cnf.xml

• SCCP-dictionary.xml

• Phonemodel-dictionary.xml

• Phonemodel-tones.xml

Files critical to the IP phone

TFTP Server

7960Firmware

7940Firmware7920

Firmware7912Firmware7905

Firmware7902Firmware7910

Firmware

Files (Cont.): Firmware

• Firmware is installed in flash with the Cisco CME software or individually as needed

• Served up by the TFTP server on the Cisco CME router

• The command tftp-server flash:firmware-file-name

CMERouter1#show flash-#- --length-- -----date/time------ path1 399514 Mar 1 2002 12:56:28 P00305000301.sbn2 22649180 Mar 1 2002 12:38:00 c3725-ipvoice-mz.123-7.T.bin3 321939 Mar 1 2002 12:55:58 CP7902010200SCCP031023A.sbin4 317171 Mar 1 2002 12:56:06 CP7905010200SCCP031023A.sbin5 317968 Mar 1 2002 12:56:10 CP7912010200SCCP031023A.sbin6 700651 Mar 1 2002 12:56:18 CiscoIOSTSP.zip7 369950 Mar 1 2002 12:56:22 P00303020214.bin8 333822 Mar 1 2002 12:56:30 P00403020214.bin9 47904 Mar 1 2002 12:56:54 S00103020002.bin10 301298 Mar 1 2002 12:56:56 ata18x-v2-16-ms-030327b.zup11 496521 Mar 1 2002 12:57:22 music-on-hold.au12 1908762 Mar 1 2002 12:56:54 P00503010100.bin13 21 Mar 1 2002 12:56:18 OS7920.txt14 839984 Mar 1 2002 12:57:18 cmterm_7920.3.3-01-06.bin……33 307067 Mar 1 2002 12:56:02 CP79050101SCCP030530B31.zup34 710144 Mar 1 2002 12:57:06 cme-gui-3.1.1.tar

7905Firmware

7940Firmware

7960Firmware

Files (Cont.): Device Configuration XML File <device> <devicePool> <callManagerGroup> <members> <member priority="0"> <callManager> <ports> <ethernetPhonePort>2000</ethernetPhonePort> </ports> <processNodeName>10.15.0.1</processNodeName> </callManager> </member> </members> </callManagerGroup> </devicePool> <versionStamp>{Jan 01 2002 00:00:00}</versionStamp> <loadInformation>P00303020214</loadInformation> - <userLocale> <name>English_United_States</name> <langCode>en</langCode> </userLocale> <networkLocale>United_States</networkLocale> <idleTimeout>0</idleTimeout> <authenticationURL /> <directoryURL>http://10.15.0.1/localdirectory</directoryURL> <idleURL /> <informationURL /> <messagesURL /> <proxyServerURL /> <servicesURL /> </device>

SEPXXXXXXXXXXXX.cnf.xml

* XXXXXXXXXXX = to the MAC address

Files (Cont.): Default XML File

XMLDefault.cnf.xml

* Notice there is no ATA or 7914

Default

Files (Cont.): Language Specific XML Files

<?xml version="1.0" encoding="ISO-8859-1" ?><phrases><phrase i="173" t="Login"/><phrase i="172" t="Flash"/><phrase i="171" t="Acct"/><phrase i="170" t="Incompatible device type"/><phrase i="169" t="Another Barge exists"/><phrase i="168" t="Failed to setup Barge"/><phrase i="167" t="Barge" /><phrase i="166" t="Network congestion,rerouting" /><phrase i="165" t="CallBack" /><phrase i="164" t="SAC" /><phrase i="163" t="DND" /><phrase i="162" t="TrnsfVM" /><phrase i="161" t="SetWtch" /><phrase i="160" t="Intrcpt" /><phrase i="159" t="ImmDiv" /><phrase i="158" t="Voicemail"/><phrase i="157" t="RmLstC"/><phrase i="156" t="Unknown Number"/><phrase i="155" t="Not Enough Bandwidth"/><phrase i="154" t="Private"/><phrase i="153" t="Park Number"/><phrase i="152" t="Conference"/><phrase i="151" t="Error Mismatch"/><phrase i="150" t="Error Unknown"/><phrase i="149" t="Error Pass Limit"/>

7960-dictionary.xml

SCCP-dictionary.xml

Contents will vary based upon language selected with the user-locale command

Language

Files (Cont.): Call Progress XML File

7960-tones.xml

Contents will vary based upon call progress tones selected with the network-locale command

Call Progress

Ephone-dn and Ephone

Ephone-dn

A DN and Extension number are equivalent

Line and voice port are equivalent

Has a unique tag or sequence number assigned when the ephone-dn is created

Can have one or more telephone numbers associated with it

Can have one voice channel or two voice channels

Creates one or more telephony system pots dial peers when the ephone-dn is initially configured

DN1 and DN2

Primary/Secondary extensions configured on a single line ephone-dn where the primary is an internal extension number and the secondary is an E.164 number

One phone extension on a dual line ephone-dn for ephone-dns that need call waiting, consultative transfer and conferencing

DN1Primary extension number on a single line ephone-dn that can make or receive one call at a time

ephone-dn

ephone-dn dn-tag [dual-line]ephone-dn dn-tag [dual-line]

router(config)#

• This command is used to create an extension (ephone-dn) for a Cisco IP phone line, an intercom line, a paging line, a voice-mail port, or a message-waiting indicator (MWI).

number dn-number secondary dn-number [no-reg [both | primary]]number dn-number secondary dn-number [no-reg [both | primary]]

router(config-ephone-dn)#

• This command is used to associate a DN number with the ephone-dn instance

Ephone-dn (Cont.)

Ephone

MAC 000F.2470.F92A

MAC 000F.2470.F92E

MAC 000F.2470.F92B

ATA 188

Button 1

Analog 1

Analog 2

Button 1

Button 2

Button 3

Button 4

Button 5

Button 6

MAC 000F.2470.F92D

• Software configuration of a physical phone

• Has a unique tag or sequence number assigned when the ephone is created

• Can be an IP phone, analog phone attached to an ATA

• The MAC of the IP phone or ATA is used to tie the software configuration to the hardware

• The hardware is auto detected for all supported models except the ATA and 7914 expansion module

• Can have one or more ephone-dn(s) associated with the ephone

• Number of line buttons will vary based on the hardware

ephone phone-tagephone phone-tag

router(config)#

• Creates an ephone instance and enters ephone configuration mode

mac-address mac-addressmac-address mac-address

router(config-ephone)#

• Assigns the physical IP phone by MAC address with this instance of an ephone

Ephone (Cont.)

button button-number {separator} dn-tag [[button-number {separator} dn-tag]…]button button-number {separator} dn-tag [[button-number {separator} dn-tag]…]

• Associates the ephone-dn(s) with a specific button(s) on the IP phone

type {7940 | 7960} addon 1 7914 [2 7914]type {7940 | 7960} addon 1 7914 [2 7914]

• Defines the device as a 7914 module(s)

Ephone (Cont.): Basic Example

CMERouter(Config)#ephone-dn 7CMERouter(Config-ephone-dn)#number 1001CMERouter(config)#ephone 1CMERouter(config-ephone)#mac-address 000F.2470.F8F8CMERouter(config-ephone)#button 1:7

MAC 000F.2470.F8F8

ephone 1

Button 1

ephone-dn 7: one virtual port

000F.2470.F8F8

Ephone (Cont.): Example Multiple Ephones

• Four physical phones

• Four ephones defined

• Four ephone-dns defined

ATA-186/188

Ephone (Cont.): Example Multiple Ephones Configuration

CMERouter(config)#ephone-dn 10 dual-lineCMERouter(config-ephone-dn)#number 1004CMERouter(config)#ephone-dn 11 dual-lineCMERouter(config-ephone-dn)#number 1005CMERouter(config)#ephone-dn 12dual-lineCMERouter(config-ephone-dn)#number 1006CMERouter(config)#ephone-dn 13 dual-lineCMERouter(config-ephone-dn)#number 1007CMERouter(config)#ephone 1CMERouter(config-ephone)#mac-address 000F.2470.F8F1CMERouter(config-ephone)#button 1:10CMERouter(config)#ephone 2CMERouter(config-ephone)#mac-address 000F.2470.A302CMERouter(config-ephone)#button 1:11CMERouter(config)#ephone 3CMERouter(config-ephone)#mac-address 000F.2470.66F6CMERouter(config-ephone)#button 1:12CMERouter(config)#ephone 4CMERouter(config-ephone)#mac-address 000F.2470.7B54CMERouter(config-ephone)#type ataCMERouter(config-ephone)#button 1:13

Configuration example

Ephone (Cont.): Multiple Ephone-dns

• Two physical phones

• Four dual line ephone-dns defined

• Two ephones defined

1008 on line 1

1009 on line 2

1010 on line 1

1011 on line 6

Button 1

Button 2

Button 1

Button 6

Ephone (Cont.): Multiple Ephone-dns Configuration Example

CMERouter(config)#ephone-dn 14 dual-lineCMERouter(config-ephone-dn)#number 1008CMERouter(config)#ephone-dn 15 dual-lineCMERouter(config-ephone-dn)#number 1009CMERouter(config)#ephone-dn 16 dual-lineCMERouter(config-ephone-dn)#number 1010CMERouter(config)#ephone-dn 17 dual-lineCMERouter(config-ephone-dn)#number 1011

CMERouter(config)#ephone 5CMERouter(config-ephone)#mac-address 000F.2470.FAA1CMERouter(config-ephone)#button 1:14 2:15CMERouter(config)#ephone 6CMERouter(config-ephone)#mac-address 000F.2470.A7E2CMERouter(config-ephone)#button 1:16 6:17

Multiple line ephone configuration example

Single Line Ephone-dn

• The ephone-dn creates one virtual voice port

• One call to or from this ephone-dn at any one time

CMERouter(Config)#ephone-dn 1 CMERouter(Config-ephone-dn)#number 1001

1001One channels

One virtual voice port

Dual Line Ephone-dn

• The ephone-dn creates one virtual voice port

• The “dual-line” keyword indicates two voice channels for calls to terminate on an ephone-dn extension

• Use on ephone-dns that need call waiting, consultative transfer, or conferencing on one button

• Cannot be used on ephone-dns used for intercoms, paging, MWI or MoH feeds

CMERouter(Config)#ephone-dn 2 dual-lineCMERouter(Config-ephone-dn)#number 1002

1002Two channels

One virtual voice port

max-dn max-dnmax-dn max-dn

router(config-telephone)#

• Sets the maximum definable number of ephone-dns that may be configured in the system

Number of Ephone-dns max-dn Command

• The maximum number of ephone-dns supported is a function of the license and hardware platform

• The default is zero

Number of Ephone-dns (Cont.)

CMERouter(config-telephony)#max-dn 10 CMERouter(config-telephony)#max-ephones 10

Attempting to create an 11th ephone-dn will fail

Initial Phone Setup

Manual Setup (Cont.): Commands Overview

• tftp-server flash:filename

• telephony-service

• max-ephones max-ephones

• max-dn max-directory-numbers

• load phone-type firmware-file

• ip source-address ip-address [port port]

• create cnf-files

• keepalive seconds

Commands needed to configure a basic telephony service

7940/60 Firmware

tftp-server flash:filenametftp-server flash:filename

CMERouter(config)#

• Allows a file in flash to be downloadable with TFTP

Manual Setup (Cont.): tftp-server Command

tftp-server flash:P00303020214.bin

tftp-server flash:cmterm_7920.3.3-01-06.bin

Available through TFTP7920

Firmware

7910 Firmware

telephony-servicetelephony-service

CMERouter(config)#

• Enters telephony service mode

max-ephone maximum-ephonesmax-ephone maximum-ephones

CMERouter(config-telephony-service)#

• Sets the maximum number of ephones that may be defined in the system (default is 0)

max-dn maximum-directory-numbersmax-dn maximum-directory-numbers

• Sets the maximum number of ephone-dn that may be defined in the system (default is 0)

Manual Setup (Cont.): Telephony Service Commands

load model firmware-file load model firmware-file

• Associates a firmware file with the model of IP phone

Manual Setup (Cont.): Firmware Association

7940/7960

telephony-service

load 7960-7940 P00303020214

load 7920 cmterm_7920.3.3-01-06.bin

load 7910 P00403020214

Filenames are case-sensitive

7940/60 Firmware

7920 Firmware

7910 Firmware

ip source-address ip-address [port port]ip source-address ip-address [port port]

• Identifies the address and port through which IP phones communicate with Cisco CME

Manual Setup (Cont.): Source IP and Port

telephony-service

ip source-address 10.90.0.1 port 2000

10.90.0.1

Default

create cnf-filescreate cnf-files

• Builds the specific XML files necessary for the IP phones

Manual Setup (Cont.): Create XML Files

telephony-service

create cnf-files

10.90.0.1

000F.2473.AB14

SEP000F2473AB14.cnf.xml

keepalive secondskeepalive seconds

• Sets the length of the time interval between keepalive message from the IP phones to Cisco CME

Manual Setup (Cont.): Keepalive

• Default is 30 seconds, range is 10 – 65535 seconds

• If 3 keepalives are missed in a row, the device will have to register again

telephony-service

keepalive 10

Keepalive

Manual Configuration: Example

ip dhcp pool MMAE

network 10.90.0.0 255.255.255.0

default-router 10.90.0.1

option 150 ip 10.90.0.1

telephony-service

load 7910 P00403020214

load 7960-7940 P00303020214

create cnf-files

max-ephones 10

max-dn 10

auto assign 100 to 120

keepalive 10

ip source-address 10.10.0.1 port 2000

ephone-dn 1 dual-line

number 401

ephone 1

mac-address 001B.53AD.6113

button 1:1

Manual Configuration: Example

number 402

ephone 2

mac-address 0019.306F.F5C2

button 1:2

number 301

ephone 3

mac-address 1930.6FF5.C201

type ata

button 1:3

number 302

ephone 4

mac-address 001B.53AD.9743

type ata

button 1:4

What is VoIP?

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