Connections: Middleware and Network

Kittiphan Techakittiroj (21 . . 2566เม ย )

Connections:Middleware and Network

Kittiphan Techakittiroj

[email protected]


• Clients: need services

• Servers: serve the need

• Middleware: Connection between Clients & Ser

vers

– software: standard, protocol, commercial softw

are

– hardware: physical connection, router, gateway

Introduction


• tiny shops or individual

• small shops or departments

• intergalactic enterprises

• post scarcity world

Configuration of Client/Server


• Both client and server are on the same

machine

• Powerful machine: usually the case of current

available machine

• Robust Operating System

Tiny Shops or IndividualConfiguration of Client/Server


• one server/many clients: all clients access one server

• Popular architecture of local area networks

• Easy for administration

– Known clients -> customized for specific needs

– Administrator has full control over server

Small Shops or DeparmentsConfiguration of Client/Server


• many servers/one client: client designed to access

many servers

• Current of Internet/Intranet Application

Intergalactic EnterprisesConfiguration of Client/Server


• Expandable, Flexible, Fault Tolerance

• Require a good middleware: e.g. security, bandwi

dth

Intergalactic Enterprises (cont.)

Configuration of Client/Server


• Distributed systems: each individual machine acts

as both client and server

• Require powerful resources

Post-Scarcity WorldConfiguration of Client/Server


• Combination of all

– LAN with Internet

• Need to consider the advantage, disadvantage

• Other arrangement is possible: depends on

definition

– number of clients or servers

– geographical boundary

Real WorldConfiguration of Client/Server


• Client Building Block

• Server Building Block

• Middleware Building Block

Inside Middleware


• Usually built-in OS

• Graphical User Interface (GUI)

• Object Oriented User Interface (OOUI)

• Web Browser

• Distributed System Management (DSM)

• etc.

Client Building BlockInside the Middleware


• SQL Database Servers

• TP Monitors

• Groupware Servers

• Object Servers

• Web Server

• DSM Component

• etc.

Server Building BlockInside the Middleware


• Transport Stack

• Network Operating Systems (NOS)

• DSM

• Service Specific

Middleware Building BlockInside the Middleware


• For n-tier system

• Might be future trend of network

application

Server-to-Server Middleware


• Size of Network

– Local Area Network (LAN)

– Wide Area Network (WAN)

• Standard Protocol: TCP/IP, NetBIOS, IPX/SPX, A

ppleTalk

• Layer Concept: ISO Layer, Internet Protocol Suite

Network Connection


• The way of connect computers together

• WAN will be irregular (f)

Network Topology

Computer Networks by Andrew S. Tanenbaum


• Split to small functionality connect to each other

• Easy to implement, maintenance

Layer ConceptNetwork Connection

Internet & Intranet Engineering by Daniel Minoli


• Link Layer: interconnection (hardware &

software)

• Network Layer: networking computers

• Transport Layer: delivery service

• Application Layer: Telnet, FTP, SMTP

Internet Suite (TCP/IP protocol)Network Connection: Layer Concept


• Connection-Oriented Service: connection need to

be established first

• Connectionless Service

Connection TypeNetwork Connection: Layer Concept



• Each difference layer contains specification

• Physical Layer: signal specification

• Other Layers: header containing information

Specification & HeaderNetwork Connection: Layer Concept



• Hubs

• Bridges

• IP Switches

• Routers

• Gateways

Interconnecting DevicesNetwork Connection


Hubs, Switches, Birdges, RoutersNetwork Connection: Interconnecting Devices

• Definition changing with time

• Intelligence …: make difference disappered

Internet & Intranet Engineering by Daniel Minoli


• Logical Network

Driver

• Stack Sandwich

• Protocol

Matchmakers

(optional)

• Transport-

Independent APIs

Transport Stacks Middleware


• Cover: Signal, Medium, Data

• Absolute Bandwidth: the width of the

frequency spectrum of the signal

• Effective Bandwidth: less than 3dB power drop

• Commonly used as the amount of bits that

can be transferred within one unit time (bit-

rate)

Bandwidth


How much bandwidth is enough?Bandwidth

• Depend on Application and Taste

Bandwidth Remark

AudioCD Quality 706 kbit/s 16 bit, 44.1 ks/s

Digital Phone Quality 64 kbit/s 8 bit, 8 ks/s

VideoMinimum Quality 566 kbit/s 1024x768, 30 fps, 24 bits

TV Quality (uncompressed) 96 Mbit/sTV Quality (compression) 6 Mbit/s

Data Requirements depends


Bandwidth AvailableBandwidth

• Depend on Location & Media & Cost


Bandwidth for LANBandwidth: Bandwidth Available


Speed DeploymentEthernet 10 Mbit/s WidespreadToken Ring 4/16 Mbit/s Flat marketFast Ethernet 100 Mbit/s Growing very rapidlyFDDI 100 Mbit/s Declining marketshareGigabit Ethernet 1 Gbit/s Growing rapidlyATM 25 Mbit/s -

2.4 Gbit/sDeclining marketshare as a LAN replacement


Bandwidth for WANBandwidth: Bandwidth Available


Speed SpeedT1 (DS1) 1.54 Mbit/s OC-3 155.52 Mbit/sE1 2.04 Mbit/s OC-12 622.08 Mbit/sE2 8.44 Mbit/s OC-24 1.244 Gbit/sE3 34.36 Mbit/s OC-48 2.488 Gbit/sT3 (DS3) 44.73 Mbit/s OC-96 4.976 Gbit/sOC-1 51.84 Mbit/s OC-192 10 Gbit/sOC-2 103.68 Mbit/s OC-768 40 Gbit/s

Physical Interconnect Technology


Bandwidth for WAN cont.

Bandwidth: Bandwidth Available

• Technology on top of Cable/Physical Technology

Max. Speed

App. Packet Size Deployment

Frame Relay 45 Mbit/s (T3/E3)

Data Voice

Variable length 4096 bytes max.

Wide

SMDS 45 Mbit/s (T3)

Data Variable length 9188 bytes max.

Limted and declining

ATM 2.4 Gbit/s (OC-48)

Data Voice Video

53 byte cells Limited but growing

Packet-Switching


Bandwidth from Home to WANBandwidth: Bandwidth Available

SpeedV.34 28.8 kbit/sV.90 56 kbit/s down, 33.6 kbit/s upISDN BRI 128 kbit/sISDN PRI 1.544 Mbit/sT1 1.544 Mbit/sHDSL up to 1.5 Mbit/sADSL up to 6 Mbit/s down, 640 kbit/s upCable Modem up to 10 Mbit/sB-ISDN (ATM/Sonet)

100 Mbit/s and more


Reference Books

Client/server survival guide 3rd edition by Robert Orf

ali, Dan Harkey, Jeri Edwards (John Wiley & Son

s: 1999)

Computer Networks 3rd edition by Andrew S. Tanen

baum (Prentice Hall: 1996)

Internet & Intranet Engineering by Daniel Minoli (M

cGraw Hill: 1997)

Documents

Connections: Middleware and Network