Technical Seminar Presentation Presented by :- Plaban Kumar Rout (EC ) “Wireless ATM & Congestion Control ” Presented by Plaban Kumar Rout Roll# EC At NIST,Berhampur Under the guidance of Mr. Dutikrushna Panda

Technical Seminar Presentation Presented by :- Plaban Kumar Rout (EC ) Wireless Technologies ? Wireless LAN technologies comprise of infrared (IR), UHF radio, spread spectrum, and microwave radio, ranging from frequencies in the region of GHz in Europe (900 MHz in the U.S.) to infrared frequencies  Spread Spectrum (CDMA)  Time Division Multiple Access (TDMA)

Technical Seminar Presentation Presented by :- Plaban Kumar Rout (EC ) ATM (Asynchronous Transfer Mode) In ATM networks, the data is divided into small, fixed length units called cells. The cell is 53 bytes. Each cell contains a 5-byte header, which comprises of identification, control priority and routing information. The rest 48 bytes are the actual data. There are two fundamental types of ATM connections  Permanent Virtual Connections (PVC) Set up by some external mechanism,typically network management.  Switched Virtual Connections (SVC) Set up automatically through signaling protocol,does not require the manual interaction needed to set up PVCs  How ATM Works?

Technical Seminar Presentation Presented by :- Plaban Kumar Rout (EC )  Fixed Wireless Components  Mobile End Users  Mobile Switches with Fixed End Users  Mobile Switches with Mobile End Users  Interworking with PCS  Wireless Ad Hoc Networks Wireless ATM Components Wireless ATM ATM is considered to reduce the complexity of the network and improve the flexibility while providing end-end consideration of traffic performance.

Technical Seminar Presentation Presented by :- Plaban Kumar Rout (EC )  Architecture Key Issues Wireless Base Station Connected Through An ATM Switch

Technical Seminar Presentation Presented by :- Plaban Kumar Rout (EC )  Cell Size The ATM cell size (53 bytes) is designed for 64kbps or higher. Each cell contains a 5-byte header, which comprises of identification, control priority and routing information. The rest 48 bytes are the actual data. There are two fundamental types of ATM connections  Virtual Circuit Management And Packet Routing Each processor that attaches to the ATM switch maintains a virtual connection to each other processor over which it passes data packets. The processors use a second, separate virtual circuit for routing updates.  Physical Layer The physical layer includes all hardware components and the wireless connections. This includes the high speed radios, order wire packet radios, ATM switch, antennas, and additional processor for configuration and setup.

Technical Seminar Presentation Presented by :- Plaban Kumar Rout (EC )  Media Access Control (MAC) Relation of wireless network (PCN) protocol layers of ATM

Technical Seminar Presentation Presented by :- Plaban Kumar Rout (EC )  Data Link Layer  Network Locations and Connection Establishment  Mobile ATM Handover Location Management Routing Addressing Traffic and QoS Control Wireless Network Management

Technical Seminar Presentation Presented by :- Plaban Kumar Rout (EC ) Why Congestion Control Needed? A Network with High Speed Links

Technical Seminar Presentation Presented by :- Plaban Kumar Rout (EC )  Connection Admission Control  Usage Parameter Control  Priority Control  Traffic Shaping Leaky Bucket Algorithm Generic Functions

Technical Seminar Presentation Presented by :- Plaban Kumar Rout (EC )  Network Resource Management Responsible for the allocation of network resources in order to separate traffic flows.  Frame Discard It may be better to drop all cells of one frame than to randomly drop cells belonging to different frames  Feedback Control The set of actions taken by the network and by the end-systems to regulate the traffic submitted on ATM connections according to the state of network elements.  ABR Flow Control The ABR service category uses the link capacity that is left over and is applied to transmit critical data that is sensitive to cell loss

Technical Seminar Presentation Presented by :- Plaban Kumar Rout (EC ) Some Early Debates  Open-Loop Vs Close-Loop 1 st one do not need end-to-end feedback,but In 2 nd approaches, the source adjusts its cell rate in responding to the feedback information received from the network.  Credit-Based Vs Rate-Based Credit-Based approaches consist of per-link, per-VC window flow control. Rate-Based approaches control the rate by which the source can transmit  Binary Feedback Vs Explicit Feedback Binary Feedback uses on bit in the cell to indicate the elements along the flow path is congested or not In Explicit Feedback, the network tells the source exactly what rate is allowed for it to send

Technical Seminar Presentation Presented by :- Plaban Kumar Rout (EC ) Conclusion  WATM has the potential to bring wireless networks a new generation  The success of WATM will be highly relies on the success of ATM/B-ISDN in wired networks  Both ATM and wireless communicates have put a lot of attention on Wireless  This report introduced the concepts in congestion control for ATM networks, and the specifications for ATM Congestion Control ATM traffic control proposed by ATM