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Kilasan Backbone Telkom Next Generation. Onno W. Purbo onno@itb.ac.id onno@indo.net.id. Philosophy. The old world Box reliability Centralized The new world Network availability Distributed. References. http://www.cisco.com http://www.lucent.com http://www.xl.com
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Kilasan BackboneTelkom Next Generation Onno W. Purbo onno@itb.ac.id onno@indo.net.id
Philosophy • The old world • Box reliability • Centralized • The new world • Network availability • Distributed
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
Outline • End User Perspective • Conceptual Framework • Next Generation Telco ..
Conceptual Framework • H.323
H.323 Benefit • Codec Standards. • Interoperability. • Network Independence. • Platform & Application Independence. • Multipoint Support. • Bandwidth Management. • Multicast Support. • Flexibility. • Inter-Network Conferencing.
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.
Komponen H.323 • Terminal • Gateway • Gatekeeper • Multipoint Control Unit (MCU)
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.
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.
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.
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.
Isu Quality of Service (QoS) • Kekurangan Bandwidth • Delay terlalu lama. • Jitter / Variasi delay.
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.
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
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.
Philosophy • The old world • Box reliability • The new world • Network availability
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).
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)
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
Prioritizing • Voice Traffic • Priority Queuing (PQ) • Data Traffic • weighted fair queuing (WFQ) • class-based weighted fair queuing (CBWFQ)
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).
Traffic Shaping • Multiple access nonbroadcast media such as ATM and Frame Relay where the physical access speed varies between two end points.
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.