summarize all slides. presented by: fazilah shahren wet020035 maisun zakaria wet020078 mazlaine...

SUMMARIZE ALL SLIDES

Presented by:

Fazilah Shahren Wet020035 Maisun Zakaria Wet020078 Mazlaine Husain Wet020081 Raziedahanin Kasim Wet020148 Sihahrihah Robani Wet020157

OSI,LAN,TOKEN

Mazlaine bt Husain(wet020081)

OSI

OSI layer: - application,presentattion,session,transport,network, data link,physical Function of the layer Peer-to-peer process: Interface between layer Organization of the layer

LAN

Definition - High speed, fault-tolerant data network - Cover a relatively small geographic area Technologies - ethernet - Token ring - FDDI Advantages & disadvantages - security and cost. Types - server-based LAN- - peer-to-peer LAN LAN transmission Method - unicast - multicast - broadcast

Topologies - Physical-bus, ring, star etc. - Logical-broadcast, token passing

Devices - repeater - hub - bridge etc

Wire/cable - UTP - STP

Fiber optic

TOKEN simple placeholder frame that is passed from station to

station around the ring. Access method: token passing Priority and reservation- station of equal priority= first come first serve Time limit- imposes time limit (any station use the ring) Problem: - monitor station: Token destroyed by noise- how

to solve. Addressing: use 6bytes address Electrical specification: -Signaling : uses differential Manchester encoding

-data rate: up to 8 Mbps Frame format -data/command frame -token frame -abort frame

Frame Relay, Asynchronous Transfer Mode (ATM): Basic, ATM: Standard

Sihahrihah Robani (wet020157)

Frame Relay Frame Relay is a networking protocol that works at the

bottom two levels of the OSI reference model : the physical and data link layers.

Two general categories : > Data terminal equipment (DTEs), which include

terminals, personal computers, routers and bridges. > Data circuit-terminating equipment (DCEs), which

transmit the data through the network and are often carrier-owned devices.

Frame Relay virtual circuit fall into 2 categories: > switched virtual circuits (SVCs) - temporary

connections. > permanent virtual circuits (PVCs) – permanently

established connections by the network provider.

Asynchronous Transfer Mode (ATM): Basic

ATM is cell relay protocol and allow high-speed interconnection of all the world’s network.

ATM combines a new set of networking features Connection oriented, based on switch technology and

fixed length cell Uses existing cable plants Wide range of speed and distance Designed for LAN/MAN/WAN/MAN applications Evolution, not revolution, from existing networks and

applications ATM is real and there is wide participation from all

market segments

ATM STANDARDS 3 main standard bodies :

ITU-T (International Telecommunication Union)

include topics such as the definition of the B-ISDN protocol model, the function and sequence of each bit in the ATM cell.

ANSI (American National Standard Institute )

adopts and adds detail to the ITU-T standards and deals with issues concerning the unique North American transmission requirements.

ETSI (European Telecommunications Standard Institute)

deals with issues concerning the European communications.

4 industry forums currently participating :

ATM FORUM working on standards for ATM LAN emulation.

IETF (Internet Engineering Task Force)

defining the standard of Internet such as TCP/IP. Organized by topic into several areas (routing, transport, security etc)

RELAY FRAME connection -oriented protocols, involveISDN-based signaling, and require similarnetwork management functions.

SMDS Interest Group (SIG)

working closely with the ATM Forum to specify access to SMDS service over anATM UNI interface.

ATM Switching,ATM Network

Fazilah Shahren(WET020035)

ATM Switching

ATM Switching:

Packet switching technology that allows voice, data, image and video traffic to be combined in evenly sized cells for high speed transmission over one access circuit.

Aim – to increase speed, capacity and overall performance.

Functions :

i) User plane - To relay data cells ( input ports-> appropriate output ports)

ii)Control Plane - represents functions related to the establishment and control of the Virtual

Paths/Virtual Channel (VP/VC) iii) Management Plane - concerned with monitoring the

controlling networks

Architecture – generic module (Functional blocks) :

1. Input Modules -performs by terminates the incoming signals and

extracts the ATM cell stream

2. Output Models - prepares ATM cell a formats on the physical network.

3.Cell Switch Fabric –to perform the routing of data cells, signaling and management cell.

4. Connection Admission control – sets of procedures that include actions taken by the network to grant or deny a virtual connection.

5. Switch Management -overall responsibility of providing key information for managing the switch and the network.

Techniques Cell Switching Fabric to relay ATM cells 2 major functions

a) Concentration, expansion, multiplexing/demultiplexing of traffic

b) Routing of buffering of traffic - 5 ATM Switching Alternatives : 1) Shared Memory Switch

2) Shared Bus Switch 3) Crossbar Switch 4) Multistage Switching

5) Banyan/Delta Switching

Switching Element Requirement : 1. Performance -Connection Blocking

- Cell Loss, Cell Insertion - Switching Delay

2. Information Rates 3. Broadcast

Queuing Methods :1. Problems2. Approaches - Input buffers - add a queue at the switch elements

inputs - Output Buffers – add a queue at the switch output - Central Queuing – add a queue between the inputs

on the outputs of switch.

ATM Networking ATM Network - high-speed networking standard

designed to support both voice and data communications

Overview - a set of hosts connected by ATM links to ATM

Switch - Designed to improve utilization and quality of

service (QoS) on high-traffic networks - slotted system – better scalability - Seamless - support data, voice, video integration - cheaper – fixed size, short address, simplicity

Structure of an ATM Network

-based on the concept of two end point devices communicating by means of intermediate switches.- 2 types of interfaces in ATM networks : a) User-to-Network Interface (UNI)

- connection is made up of end-point device and private or public ATM Switch b) Network-to-Network Interface (NNI)

ATM Networks Interfaces - UNI - NNI

- UNI Vs NNI - General operation on an ATM Network

LAN Emulation

- operation - Initialization - Registration - Address Resolution - Broadcast/Unknown Server (BUS)

- allows current applications to run on ATM networks without changes- disadvantages – ATM is hidden from application

LANE Components Virtual LANs – group of users that appear to be

interconnected by one LAN ATM Virtual LANs

ATM Adaptation Layer

- purpose is to adapt the PDUs passed down from the higher layer onto ATM cells- 2 sublayers responsible for - segmentation and reassembly (SAR)

- convergence sublayer (CS)- classification of ATM Adaptation protocols guided by

considering following parametersa) Timing Relationship – (non-) requirement for

synchronisation between the receiver and senderb) Bit rate - constant/variablec) Connection Mode - connection

oriented/connectionless

ATM : Congestion Control and Components

Maisun bt. Zakaria(wet020078)

ATM : Congestion Control provides a good traffic management important in high speed networks

Causes of Congestion:1. Exhaustion of buffer space2. Deadlock

Solve congestion control by using 2 techniques :1. Preventive (feedback-based)- prevent congestion BEFORE it can occur- Preventive Techniques: Leaky bucket & Token bucket2. Reactive (reservation-based)- responds to congestion AFTER it occurs & then attempt to stop it- Reactive Techniques: Load shedding, Choke packets

ATM: Components1) ATM Networks

- connection-oriented. - contains 2 basic components: an endstation, and an ATM switch

2) Virtual Path (VP) Switch- Route the cell using only the VPI (Virtual Path Identifier) - The switching table stores 4 pieces information per row:

i. Arrival interface numberii. Incoming VPIiii. Corresponding outgoing interface numberiv. New VPI

3) Virtual Path Connection (VPC) Switch- are provided for the purpose of user-user, user-network, network-network information transfer.- Advantages

*Simplified network architecture *Increased network performance and reliability

4) ATM Switching Techniques

i. Shared Memory Switch- technique that uses a common memory for the storage of cells and switching fabric.

ii. Shared Bus Switch- approach utilizes a bus or dual bus architecture to switch cell traffic.

iii. Crossbar Switch- matrix-like space division technique that physically interconnects any of the N inputs to any of the N outputs at crosspoints.

iv. Multistage Switching- uses a similar concept to the crossbar switch technique.

v. Banyan/Delta Switching- a concept of an interconnection of stages of switching elements.

ATM: ArchitectureATM: DescriptionATM: Issues

Raziedahanin Kasim (Wet020148)

ATM: Architecture(word document)

ATM Cell Structure & Format

- Cell structure- Header & payload

- 2 Different format- UNI & NNI

ATM Network Architecture-Connection is point-to-point-Switched based traffic-2 types of architecture

- Private network architecture- Public network architecture

ATM Connection- 2 level of connections

- Virtual channel connection (VCC)- Virtual Path connection (VPC)

4 ATM Architecture - 2 components

- End point devices- Switches

- 3 layers- ATM Adaptation Layer- ATM Layer- Physical Layer

ATM: Descriptions

Asynchronous Transfer Mode (ATM) is a connection oriented data transmission protocol based on groups of fixed length cells.

The basic characteristics of ATM are:1. Cell-based technology 2. Service transparent 3. Connection-oriented 4. User-to-network Interface (UNI) 5. Occupies one layer in network architecture

3 important layers in Layered Architecture of an ATM network are:

1. Physical Layer: responsible for transmitting and receiving ATM cells over a physical transport medium.

2. ATM Layer: managing the sending and receiving of cells between the user and the network.

3. ATM Adaptation Layer (AAL): makes it possible for the ATM Layer to support multiple services and traffic types.

ATM: Issues

1. Congestion Control- Main cause for congestion – unpredictable statistical

of traffic flow- 2 types – Reactive CC & Preventive CC

2. Admission Control- Based on performance metrics - link-level performance measures

- connection-level performance measures3. Traffic Policing

- 2 mechanisms - Bit dropping method- Feedback preventive control

4. Traffic Analysis and Prediction- 2 approaches

- Based on a presumed traffic model- Based on traces of actual traffic streams

6. Scheduling- Used multiplexing policy