Conventional Memories

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Index

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The Guide to Mobile Connectivity

Technology Background Paper

Source:TEG NF

Executive summary

WARNING:

Toshiba considers the information in

this paper correct to the best of its

knowledge at the time of printing.

Toshiba assumes no liability for errors

omissions or discrepancies, nor for any

damages incurred based upon use of

the information contained herein.

The Complete Guide to Mobile Connectivity

The full technology background paper on the subject of mobile

connectivity is a relatively detailed survey divided into three parts.

These cover: the technologies available for expansion and connectivity;

the hardware options that mobile computer users can choose from

in order to get connected; the range of systems used in networking

and long-distance data transfers now and in the near future.

The following paragraphs sum up the information and reasoning

included in the full paper. Before anybody writes about this

subject we strongly recommend that they read all or at least the

appropriate parts of the full paper. Only there will they find the

requisite amount of detail to convince and persuade prospective

users or buyers.

Introduction

This looks at the development of computers and how it

relates to the central question of accessing information.

Today's growth in connectivity is the latest manifestation of

the desire to get information flowing.

1. The technology of expansion - the nuts and bolts of connectivity

ISA The current Industry Standard Architecture came from IBM

in the mid eighties. It's data throughput is limited and now

looking a little old. It is the basis of 90% of PC expansion

today including the highly successful PCMCIA format.

MCA Micro Channel Architecture was IBM's expensive answer to

the need to improve ISA. Relatively unsuccessful, even

IBM's mobile PCs use ISA today.

EISA Extended Industry Standard Architecture was designed by

a group of PC manufacturers as a response to IBM's MCA.

Despite improvements over ISA it has never really caught

on. Nowadays only used in desktops.

PCI Peripherals Component Interconnect is the latest new bus

standard. Designed by Intel with general industry-wide

support it is very fast and looks set to replace ISA in the next

year or so. There is even a PCMCIA version for mobile PCs.

The section includes a table comparing all bus standards.

VESA The Video Electronics Standards Association was

instrumental in bringing agreed standards to video output

and boosted the idea of local buses through the widely

used VL-bus standard which is now competing with PCI.

SCSI Small Computer Standard Interface, a left over from the

workstation world that is now finding growing popularity

as an expansion bus system for PC external devices. It is

starting to appear in mobile PCs principally for CD-ROM

usage. A list of SCSI devices is included.

Proprietary standards

Many companies used these for expansion in the past,

especially in mobile PCs. They now limit choice so should

be avoided in current PC purchases.

2. Hardware choices: using the right connectivity option

PCMCIA The Personal Computer Memory Card International

Association began by seeking an agreed standard for

memory expansion. With PCMCIA 2.0 it brought many I/O

devices within its range. It's credit-card-sized expansion

modules are now the main method of expansion in mobile

PCs for everything from flash cards to modems, sound cards,

SCSI expansion and even mini hard disks.

PCMCIA 3.0

Is a further development of this handy format to match

today's advanced 32-bit processors. It is PCI-oriented for

speed but still ISA compatible.

Toshiba and PCMCIA

reviews Toshiba's involvement with PCMCIA and looks at

Toshiba's implementation of this standard listing PCs & slots.

Using PCMCIA cards

describes the various types of card now available in the

different formats and explains the advantages of PCs with

two separate as opposed to two stacked slots. It describes

the usefulness of a full Type III slots and looks at the use of

Type III in the future. A table listing current and possible

future PCMCIA cards is included.

S&CS The Socket and Card Services section looks at the important

role the this software plays in controlling and monitoring

PC card usage. It explains the advantages S&CS bring using

examples of hot-plugging and hot-swapping.

Plug and Play

The name Microsoft, Intel and others gave to a new con-

cept designed to make PC expansion in all forms easier to

do and user friendly. It will cover older forms of expansion

(see above) as well as the new PCI and PCMCIA methods.

Docking stations

are desktop units into which mobile PCs can be slotted to

gain access to larger expansion options. This section

explains their usefulness for mobile PC users and analyses

"intelligent" systems. PCI and Plug and Play will make such

units more important and flexible in the future.

Port replicators

The differences between port replicators and docking

stations and possible future developments.

3. Ways of keeping in touch - types of networks

Office networking

looks at the hardware choices for mobile PCs in office

networks, in particular two growing technologies:

Infra-red networks allow cableless network connections as

long as the

computer stays in the same room. The work of the Infra-red

Development Association (IRDA) is described as well as

future development options;

Radio networking

is the only option which allows computers to roam within

companies. Growth may be linked to the success of local

radio telephony in businesses. A Dataquest forecast for the

development of this type of technology is included.

Long distance data

reviews the growth in the exchange of data over

telephone lines using modem technology. It mentions ISDN

and then looks at the latest trends in modems including the

development of the latest V.32 standard, the inclusion of

fax functionality and the possible future development of

soft modems. The various V standards for modem transfer

rates are listed with their speeds.

Radio systems

offer full mobility benefits. Only with radio contact is the

flow of information truly free from both ends. But radio

options for data are complicated.

Paging systems

considers their less successful relevance to data exchange.

Analogue radio systems

considers the current state of radio technology for data

transfers and its problems. The Toshiba T1850 models/DeTeMobil

Modacom net first full system is described.

Digital transfers

looks at the possibilities that GSM will bring for long-

distance digital radio networks in the future. It considers

current radio developments such as the German D1

network with a PC card. It then looks at future options

when sound becomes standard in PCs and when the

hardware for radio data transfers can be miniaturised

enough to fit inside a notebook.

Nigel Fusedale, Toshiba