Guest editorial

Small and home networks

In recent years the converging digital tech-

nologies of television, publishing, telephony and

computers, the ‘‘multimedia revolution’’, com-

bined with access to broadband, has prompted

the development of a multitude of high-speed

applications in the World Wide Web and the

digitization of everyday life. In parallel, there has

been a paradigm shift at the network edge. An

immediate impact of this evolution is the ever-

increasing demand for Internet bandwidth, the

more intelligent use of already available re-

sources and the use of overlay networks in the

home. Cable, DSL and satellite networks bring

megabits per second of information and enter-

tainment data to the edge of the home and Small

Office Home Office (SOHO). Bridging the last

mile, the great motivator of the mid-1990s has

been replaced by a new need. The provision of

broadband is becoming the distribution of band-

width and services in the home. The focus is

moving from bandwidth to applications.

Why? Because the nature of the customer pre-

mises has changed. In the past network designers

were considering that once the WAN hit the home

it would find a single device, more often than not a

PC; this was the modem and telephone-line model.

Now, homes and SOHOs often contain networks

of heterogeneous devices that communicate and

share resources. Broadband also enables rich

content to be sent to the home as well as integrated

multimedia. This combination associated to the

means to distribute it in the home creates the in-

centive for new networking paradigms.

Consequently, because of the emergence of the

home networks, the nature of networking itself is

changing dramatically. It is moving away from

supporting mainly infobusiness applications into

the infotainment world where video and audio

are now predominant and new applications are

developed every day.

Home networks?

The FCC in the US as well as other govern-

ments are recognizing the strategic value of com-

petitive communications driving the current call

toward deregulation; in response, Network Service

Providers are seeking means of securing their partof the broadband business. In the US broadband

connections to homes will grow from 11 million

today to over 35 1 million by 2006 creating a multi-

billion dollar market in the next few years for ad-

vanced networking and content distribution gear.

Small networks capture this opportunity in a

unique way. The Home Local Network (HLN)

combines the broadband Internet experience, areanetworking and entertainment devices. Conse-

quently, the home, the small business or the net-

work on the go (train or planes) can provide

services to its connected devices. And in turn those

services can be rendered on smaller devices or

entertainment gear, not only with PCs or other

larger devices.

Because of the convergence of multimedia, homecontrols and traditional communications, the

nature of network appliances––especially at the

edge––is changing dramatically and creates a need

for these devices to adapt to consumer demand.

1 Jupiter Media Matrix 2001.

1389-1286/03/$ - see front matter � 2003 Elsevier Science B.V. All rights reserved.

doi:10.1016/S1389-1286(03)00216-0

Computer Networks 42 (2003) 1–5

www.elsevier.com/locate/comnet

It is well known that a large percentage of PC

sales are now for the second or third multimedia-

enabled computer: laptops for work and school,

home servers, etc. We all carry cell phones that are

more and more Internet enabled. Our palmtops

can carry wireless networking gear, both WLANand cellular. Audio and video equipment, even

appliances, have Web interfaces and embedded

networking capabilities. New gaming systems en-

able users to play across the Net. But filling our

homes and offices with multiple digital means of

communications, that generally do not communi-

cate, and our lives with digital files that are scat-

tered and lost across multiple systems will notbring any added value. To increase the value of the

digital lifestyle, home networks will foster the de-

velopment of new protocols for connecting to and

managing the digital media we are encountering

and using every day.

There are already well established standards

that have started the evolution from disconnected

devices to integrated services. An immediate im-pact of the growth of home networking is the ever-

increasing demand for connectivity in all forms

and Internet connectivity in particular. In the

home environment the all-IP network is emerging

as the network layer of choice. Hence, in Internet

terms, the home becomes another subnet. This

subnet has some specific requirements to accom-

modate the conflicting requirements of the trafficentering the home. There is the guaranteed high

priority traffic, including real-time applications

such as high quality video streaming or voice over

IP. And, even less QoS critical applications, such

as E-mail and Web surfing may end up consuming

important resources or requiring guaranteed de-

livery.

Let us look at what seems to be a simpleproblem: the sharing of devices. Disk space,

memory or peripherals like DVD players are more

than often tied to one device. The view of the small

network as a collaborative entity is still in infancy.

Yet the promises are great: use the CPU on a

computer when ‘‘in sight’’ instead of a slower

palmtop; view DVD movies or training videos on

a large television set instead of a small screen; andhave content move with the user. This helps use

the right device when needed and at the same time

can offer higher quality and leverage the home�scapital investment.

Home Networks will incorporate the applica-

tions that include the well known functions re-

quired by the home user, such as MP3 playing,

video streaming and Web access, but also provideadvanced networking functions based on wireless

technology, support for quality of service and re-

source management and security/privacy function-

ality. In addition, advance archiving based on Web

technology and macro information allows tracking

the variety of digital media the end user needs.

Technologies and hardware

Over 95% of US homes are passed by cable.

With a steady annual growth rate of 32%, digital

cable is forecast to nearly overtake analog usage

by 2006 accounting for 67% of cable subs by year-

end 2006. 2 Add to this the number of ADSL users

and the result is that broadband in the home is areality. All of this offers a solid incentive to intel-

ligently distribute content in the home.

The rapid rise of WIFI as a local networking

solution, with 11 Mbps and 23+ million units by

2005, shows that wireless is a preferred solution for

reaching the end devices. 3 New higher bandwidth

standards such as 802.11a and Ultra Wide Band

offer high-speed alternatives in the 10s of Mbpswith better performance. For example, the 802.11a

standard allows the definition of multiple priorities

to enable quality of service and allow multimedia

services to be guaranteed at several predefined

and/or customizable levels of performance. The

use of the Bluetooth technologies for personal area

networks also makes part of the network offerings

in the HLN.While the use of the wireless medium to reach

all rendering engines in the end-user network is

compelling, other wireline technologies, such as

phone lines (HPNA) or powerline also allow

connectivity to IP appliances––all with expected

rates of several Mbps.

2 MIT Internet Telephony Convergence (ITC) January 2002

Meeting.3 Forward concepts, 2001.

2 Guest editorial / Computer Networks 42 (2003) 1–5

Products and standards

The current wave of connectivity products for

the home, following the PC, is currently targeted

at entertainment. Slowly, more advanced net-working features are being integrated into broad-

cast receivers and video software. Advanced

set-top box manufacturers are developing cable

set-top boxes that combine broadcast and broad-

band. Some of these set-top boxes may soon use

wireless technologies to share capabilities with

other devices, following the success of wireless

access points and combined DSL/WLAN devices.Other startups have concentrated on flexible soft-

ware architectures that allow combining TV,

Internet access and home controls.

Internet-enabled gaming devices are also

emerging. Some gaming gear currently offers lim-

ited networking capabilities: IEEE1394 connectors

for cameras, USB connections to printers and in-

tegrated modems for Web page access. These areall interfaces that could make them peers in a

network in the future.

Finally, true home servers and wireless

gateways are starting to emerge too. They offer

connectivity, centralized management, archiving

capabilities and ubiquitous access. These will also

build on the gateway standards being currently

pushed by software and computer manufacturerssuch as the Open Service Gateway Initiative

(OSGI) and Universal Plug and Play (UPNP), that

enable connectivity amongst heterogeneous de-

vices and software, and the middleware consor-

tium�s pushing open platforms for interoperability.

It is, however, obvious that while it is an early

market; it will take off as the needs become more

important. Already, service providers are lookinginto new services and new revenues from home

networks. The opportunity for new HLN tech-

nology is huge and now.

Only D or is there a place for R too?

Phone lines, power lines and wireless LANshave enabled connectivity in small networks. But

is there networking beyond connectivity? Home

devices, while fully supporting the entertainment

and home controls required by the end user,

should also provide traditional network manage-

ment. These include real time functions to support

quality of service, resource management and load

balancing, security/privacy and also non-real time

network management such as provisioning, ac-

counting and fault tolerance.Devices in the home go on and off, hence small

networks have an aspect of ad-hocness that cannot

be disregarded. While PCs and set-top boxes and

IP appliances are more or less fixed, laptop,

palmtops and audio players are, if not mobile, at

least nomadic. Location-based networking may be

necessary and issues of handover between home,

community networks and public networks putsrequirements on quality of service management in

between the different network tiers.

There are of course a large number of such

protocols available today in the Internet. But then

there is the issue of scalability. Usually, scalability

means from large to larger, in this case it means

from larger to small, maybe really small. The need

for small and inexpensive devices in the homedictates the use of networking and software ar-

chitecture standards for implementing and man-

aging devices, ranging from cell phones and fridges

to advanced set-top boxes and multimedia PCs.

Some techniques may fail or perform poorly for

lack of CPU, memory or power. Some may be

inappropriate for reasons of complexity. The use

of a state- and connection-less architecture mayprovide robust support to a broad range of ser-

vices and the means for the HLN to interconnect

to existing infrastructure through open interfaces.

The development of lightweight protocols and

modular middleware offer some means of over-

coming the limitations of end devices. But they are

in their infancy and should not be implemented

at the expense of networking functionality.A variety of networking technologies can be

used in the HLN from wired to wireless. Hence

traffic engineering and QoS policy must be defined

to ensure that attached devices get their assigned

service level. The definition of multiple priority

and hierarchical queuing classes as well as novel

routing techniques will support future quality of

service requirements to allow services to be guar-anteed at several predefined and/or customizable

levels of performance. There is a need for novel

Guest editorial / Computer Networks 42 (2003) 1–5 3

methods to reduce signaling overhead and session

establishment delays while still following open

standards and APIs.

Recent device discovery mechanisms based on

JINI and XML will enable OS- and/or platform-

independent tools to implement advanced servicesand Web-based management tools as well as per-

sonalized user interfaces. In addition, open soft-

ware platforms can enable the gateway to rely on a

rich base of new and reliable tools to implement

advanced networking functions.

Finally, future enhancements of personal gate-

ways, taking cues from advanced cost-based rout-

ing based on end to end parameters to interlayersignaling to ad hoc networking and active routing

can also lead to interesting research in the field.

This special issue

This special issue addresses the networking

functions of a new generation of Internet/enter-tainment gateways dedicated to the Home Local

Network (HLN).

Home networking (and small networks) should

allow a network design, and a network manage-

ment environment, that fosters innovation. The

services that the Network Service Providers offer

are changing: the Internet, deregulation of com-

munications and advances in ubiquitous comput-ing technology, all are contributing to the changes.

It will be a very competitive business and designs

will need to adapt. For this reason, we will see that

the proposed approaches in this issue favor mod-

ular approaches and are more or less independent

of the source of the broadband connectivity. At this

point, we would like to express our sincere thanks

to the authors, reviewers and the Editors-in-Chieffor their efforts in putting this issue in place.

The first paper, authored by A. Ganz, K.

Wongthavarawat and A. Phonphoem proposes a

novel software architecture, called Q-Soft, for

supporting Quality of Service (QoS) in an HLN.

This architecture is implemented in the form of a

middleware between the IP and the Network In-

terface Card (NIC) layers. Using emulation, theauthors provide experimental data illustrating the

benefits of their architecture when used over

wireless and phoneline home networks.

The second paper, by P. Manzoni and J.C.

Cano, proposes a new clustering framework, called

FRANCA, which aims at minimizing the power

consumption of lightweight devices in an HLN.

Similarly to the architecture proposed in the first

paper, this framework is independent of the un-derlying mode of communication. FRANCA is

expected to be especially useful for providing inter-

operability between IEEE 802.11 and Bluetooth

mobile devices.

It used to be that space was the last frontier and

Global Area networks were the ultimate dream.

On a more human scale, and in an era of realism, it

may well turn out that the last frontier is the home.

Marie-Jos�ee Montpetit

168 Mystic Valley Parkway

Arlington, MA 02474, USA

E-mail address: mariejose.montpetit@verizon.net

David Starobinski

8 St. Mary�s Street

Boston, MA 02215, USA

E-mail address: staro@bu.edu

Marie-Jos�ee Montpetit holds a Ph.D. inElectrical Engineering from EcolePolytechnique in Montreal with afocus on coding and communicationtheory. She has been leading advancedproduct development in internet overwireless and satellite media for the last10 years. She is also active in the IETFand the IEEE and had participated inconferences and workshops, as Tech-nical Program Committee Member,Chair, Panelist and Author. Finallyshe is concerned by the training andcontinuing education of engineers and

has given professional tutorials and courses in the field of sat-ellite networks and wireless systems and directed undergraduateand graduate students. Her research interests cover Internetover heterogeneous media, quality of service, Internet perfor-mance and multimedia networking.

David Starobinski received his Ph.D. inElectrical Engineering from the Tech-nion, Israel Institute of Technology,in 1999. In 1999–2000, he was a visit-ing post-doctoral researcher at theEECS Department in the University ofCalifornia, Berkeley. In 2000, he joinedthe Electrical and Computer Engineer-ing Department at Boston University,as an Assistant Professor. Dr. Starob-inski received a fellowship for pro-spective researchers from the SwissNational Science Foundation in 1999–2000, and awards from Intel Corp. in

4 Guest editorial / Computer Networks 42 (2003) 1–5

1998 and the Gutwirth Foundation in 1996, 1998, and 1999, foroutstanding academic achievements. He also received an NSFCAREER award in 2002 for his work on Quality of Service and

multiple time-scale traffic. His research interests are in networksperformance evaluation, Internet traffic engineering, and high-speed and wireless networking.

Guest editorial / Computer Networks 42 (2003) 1–5 5