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Transcript of VoIP
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Arah Perkembangan
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Philosophy The old world
Box reliability Centralized
The new world Network availability Distributed
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References http://www.cisco.com http://www.lucent.com http://www.xl.com http://www.quicknet.net http://openh323.org http://openphone.org http://www.pulver.com
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Outline End User Perspective Conceptual Framework Next Generation Telco ..
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End User - Internet Telephone
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Komponen VoIP / Menit Telkom Rp. 75 / menit ISP Rp. 75 / menit Hook-off Service
http://www.net2phone.com
Delay <250ms
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Biaya SLI / Menit (1US$=Rp8000)
Country Peak Normal
Disc VoIP
US 9900 8300 6230 1350
Singapore
6780 5650 4240 2550
Taiwan 9960 8300 6270 4070
Jepang 11286 9400 7050 2310
Hong Kong
9960 8300 6230 2710
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Solusi Kantor Kecil / Rumah Satu (1) Saluran VoIP
Internet PhoneJACK US$150 Internet LineJACK US$220 Internet PhoneCARD US$170
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Komunitas WARNET [email protected] Free subscribe:
Komunitas e-commerce [email protected] [email protected] [email protected]
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Kebutuhan WARNET Line telepon koin Leased line analog
Regional Network / DIVNET Akses ke box JAMUS V.35 / RS.449
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WARNET “tanpa” Telkom
WARNET ke Internet Satellite DirectPC – US$200 / card KabelVision – Rp. 300.000 / bulan
Jaringan WARNET 2-11 Mbps 2.4 GHz US$250 / card
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Teknologi VoIP sederhana
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Internet Telephone
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Dialer
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Video Conference
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Internet PhoneJACK
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Connection PhoneJACK
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Internet PhoneCARD
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Voice Quality Comparison
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Solusi Gateway Sederhana
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VoiceTronix (8 port)
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VoIP untuk WARNET Investasi WARNET+ Invest Card DSP ~US$150 / kanal. Estimasi ke US biaya / menit
US$0.13 + Rp. 75 + Rp. 75 Estimasi ke US biaya SLI 001
Rp. 9900-8300 / menit
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Issue Desktop VoIP Solution Ease of Installation. Infrastructure. Flexibility. Compatibility. Ease-of-Use. Quality. Cost Growth Path. Base for Applications.
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Aplikasi Desktop VoIP IntraNet Communication Remote Call Forwarding Distributed Call Center Virtual PBX Line Doubling Personal Iphone Calling
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Personal Iphone Calling
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Intranet Communications
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Remote Call Forwarding
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Distributed Call Center
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Virtual PBX
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Line Doubling
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Mobile User
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Mobile User Internet Locator Service (ILS) Mapping Name Number
Dynamic IP
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Internet Locator Service (ILS) http://www.icq.com
ILS & chat system http://www.tzo.com
Dial your DNS name.
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Conceptual Framework H.323
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H.323 Benefit Codec Standards. Interoperability. Network Independence. Platform & Application Independence. Multipoint Support. Bandwidth Management. Multicast Support. Flexibility. Inter-Network Conferencing.
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H.323 mengatur .. Video Codec (H.261 dll). Audio Codec (G.711, G.723 dll). Data channel (T.120 dll) e-board dll. System Ctrl Unit (H.245, H.225.0 dll). H.225.0 layer – error detection, error
correction and frame sequencing.
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Open Standard
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Komponen H.323 Terminal Gateway Gatekeeper Multipoint Control Unit (MCU)
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Terminal H.323 Provide Real-Time. Provide Two-way communications. H.245 – nego channel usage &
capabilities. Q.931 – Registration/Admission/Status
(RAS). T.120 – Data Conferencing Protocols.
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Komponen H.323 H.323 Gateway
Interface H.323 terminal – WAN terminal. H.323 Gatekeeper
Address Translation (E.164 – IP) Admission Control. Authentication. Bandwidth Control. Zone Management. Call Control & Management
(e.g. VoIP – PSTN)
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H.323 Gateway Optional! Translation function between H.323
conferencing endpoints and other terminal types.
Translation between transmission formats (i.e. H.225.0 to H.221).
Translation between communications procedures (i.e. H.245 to H.242).
Translation between audio and video codecs. Performs call setup and clearing on both the
LAN side and the PSTN side.
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H.323/PSTN Gateway
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Gatekeeper The most important component
asct as a virtual switch of an H.323 enabled network.
It acts as the central point for all calls within its zone and provides call control services to registered endpoints.
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Gatekeeper Address translation from LAN
aliases for terminals and gateways to IP or IPX addresses (e.g E.164 – IP)
Bandwidth management. Route H.323 calls. Bill for calls.
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Gatekeeper Zone
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Isu Quality of Service (QoS) Kekurangan Bandwidth Delay terlalu lama. Jitter / Variasi delay.
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QoS Resource Reservation Protocol (RSVP) Real Time Protocol (RTP) Compressed Real Time Protocol (CRTP)
Traffic Shaping Queuing: Custom Queuing, Weighted Fair
Queuing. Congestion Control: Random Early Detection. Effisiensi Jaringan: link fragmentation &
interleaving.
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Metoda KompresiKompresi Kbps MIPS ms MOSG.711PCM 64 0.34 0.12
54.1
G.726 ADPCM 32 14 0.125
3.85
G.728 LD-CELP 16 33 0.625
3.61
G.729 CS-ACELP 8 20 10 3.92G.729 x2 Encoding 8 20 10 3.27G.729 x3 Encoding 8 20 10 2.68G.729a CS-ACELP 8 10.5 10 3.7G.723.1 MPMLQ 6.3 16 30 3.9G.723.1 ACELP 5.3 16 30 3.65
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MOS vs. DSP Price
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Intermediate Solution VoIP
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Interkoneksi Suara-Data-Suara
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Interkoneksi PC-Telepon
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Gatekeeper Lucent PacketStar IP Gatekeeper
23.500 DSO 2.300.000 calls / day (one zone) 7.800.000 calls / day (multi zone)
Cisco CallManager Windows NT
Quicknet H.323 Internet SwitchBoard
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Gateway Lucent PathStar
80.000 POTS 10.000 xDSL
Cisco DE-30+ 30 voice on E1
Cisco AT-2, 4, 8 Analog loop RJ-11, 2, 4, 8 POTS.
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Next Generation Telco
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Split Data & Voice Network
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Converged Enterprise Network
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Philosophy The old world
Box reliability
The new world Network availability
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Network Availability
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Network Availability Redudancy at many levels. Advanced Layer 3 Protocols:
Hot Standby Routing Protocol (HSRP). Open Shortest Path First (OSPF). Enhanced Interior Gateway Routing Protocol
(EIGRP). Multicast Routing:
Protocol Independent Multicast (PIM). Distance Vector Multicast Routing Protocol
(DVMRP).
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Campus Network
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How? – Detailed ..
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End-to-End Architecture
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Open Architecture H.323 Simple Gateway Control Protocol (SGCP) Media Gateway Control Protocol (MGCP) Session Initiation Protocol (SIP) Telephony Application Programmable
Interface (TAPI) Java Telephony Application
Programmable Interface (JTAPI)
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Low Cost of Ownership
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Hierarchical WAN Design the network must support and supply the
prerequisite QoS features. Hierarchical model to allow the most cost-
effective platforms. As the requirements for data traffic outstrip
those of voice, voice bandwidth decreases & lowering costs.
WAN links to support the minimum requirements for data + voice and video. When other applications are quiescent, the bandwidth is available for data.
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WAN QoS-Enabling Tech.
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Classification Layer 3 (IP)
IP Precedence; VoIP 5. Differentiated Services Code Point
(DSCP) Layer 2 (MAC) schemes
Voice RTP Voice UDP Voice Port 16383 - 32767
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Prioritizing Voice Traffic
Priority Queuing (PQ) Data Traffic
weighted fair queuing (WFQ) class-based weighted fair queuing
(CBWFQ)
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Prioritizing
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Link-Efficiency Techniques Voice Compression (e.g. G.723). Compressed RTP
40 byte IP+UDP+RTP 2-4 bytes. Voice Activity Detection (VAD). Link Fragmentation & Interleaving.
Frame Relay – FRF.12 Serial Link – Multilink PPP (MLP).
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Traffic Shaping Multiple access nonbroadcast
media such as ATM and Frame Relay where the physical access speed varies between two end points.
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Issue QoS - Campus Network Aggregation points where many
links aggregate into an uplink. aggregation points where speed
mismatches occur.
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QoS Campus Network The primary concern is buffer
management and the ability to provide the required queuing schemes to ensure voice gets the appropriate bounds for loss, delay, and jitter.
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QoS – Strategies Classification is a key attribute. Queuing techniques. Buffer management is also used to
ensure that excess jitter is not added for voice traffic.
To combat this, the multilayer LAN switches provide either two queues or a single queue with definable drop thresholds to bound delay.
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Application IP Telephony Unified Messaging IP Contact Center
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VoIP
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Unified Messaging
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IP Contact Center
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Migration Strategies
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Terima Kasih
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