Home and Building Networks 179

by the IEEE 802.15 working group,²⁹ are not part of home networks, although some may consider them relevant.

Wireless networks include Wi-Fi and home-cellular networks, as well as sev-eral other proprietary wireless networks. Wi-Fi is an alliance that promotes Wire-less Local Area Networks (WLANs) that are based on IEEE 802.11 standards. IEEE 802.11 standards defi ne wireless technologies for data capacities ranging from 1 to 258 Mbps links, using various modulation techniques over 2.4 or 5 GHz carrier, security schemes, and Quality of Service standards. The range of a Wi-Fi access point is tens of meters in buildings (in an “indoor” environment), and up to a few hundred meters outside (an “outdoor” environment).

There are two basic confi gurations for Wi-Fi: infrastructure and Ad-Hoc. In an infrastructure confi guration, mobile clients (such as laptops or IP phones) are con-nected to Access Points (APs), and all their communications are done through these APs (which function as Base Stations). In an ad-hoc confi guration, there are no APs, and the clients communicate among themselves, with some relaying information to other clients.

Wi-Fi may be used in public areas such as restaurants and airports (in infra-structure confi guration), to allow Internet access to bypassers, in a setup called

“hot-spots.” Recently, there have been attempts to create Wi-Fi coverage for larger areas (achieved by multiple access points), which are used as a sort of RAN that is attached to the 3G or 4G infrastructure.

Femtocells are tiny, residential “base-stations” of the cellular network, which resemble the access points of the Wi-Fi. Femtocells are extensions of the RANs and are attached to the cellular networks through the Internet links, with either DSL or the CATV infrastructure.

Wireline networks include LAN technologies (mainly Ethernet) in buildings and a variety of cable technologies in residential homes. These include Home Phone-line Networking Alliance (HPNA)³⁰ and Multimedia over Coax Alliance (MoCA) standards for data over the telephone’s copper twisted pairs or TV’s coaxial cables, and HomePlug standards for data over the electric wires (power lines). Other technologies include FireWire cabling for multimedia applications. Recently, the ITU-T initiated a Joint Coordination Activity (JCA) on Home Networking, called

29IEEE 802.15 includes several task groups that defi ne wireless personal networks (WPANs) of vari-ous types: 802.15.1 defi nes Bluetooth, and 802.15.3 defi nes high-rate WPAN, which is referred to as Ultra Wideband (UWB). UWB includes various standards for Wireless Universal Serial Bus (USB) and wireless FireWire (IEEE 1394 serial interface), and is basically based on either the WiMedia alliance’s Multi-Band Orthogonal Frequency Division Multiplexing (MB-OFDM) UWB or the UWB forum’s Direct Sequence-UWB (DS-UWB). 802.15.3c, for example, defi nes a millimeter wave (57–64 GHz) based UWB, that is supported by the WiHD consortium, for delivering High-Defi nition (high band-width video) over WPAN. 802.15.4 defi nes low-rate WPAN, such as ZigBee. 802.15.6 defi nes even smaller range networks, called Body Area Networks (BANs).

30HPNA specifi cations were approved by the ITU-T [217–220].

JCA-HN³¹ that targets a unifi ed standard for home networking over coax cables, twisted pairs, or power lines.

4.3 SUMMARY

This chapter describes access and home networks and completes our brief descrip-tion of networks. These networks use converged technologies in terms of data and telecom applications, and serve as the last link between the core networks and the customers. Access and home networks are becoming faster and more complicated, as they integrate with aggregation networks (metro networks) and multiservice plat-forms, and require network processors for effi cient functioning and implementation.

The Metro Ethernet Forum describes network integration and service convergence very clearly in its depiction of networks and architecture, as shown in Figure 4.20. By now the reader should be familiar with the terminology, technologies, and elements, as well as the way they interact and are interoperable.

31JCA-HN drafts several standards, such as G.hn—“Next generation home networking transceivers,”

G.hnta—“Generic Home Network Transport Architecture,” H.ghna—“A generic Home Network architecture with support for multimedia services,” J.290—“Next generation set-top-box core architecture,” and X.1111 (formerly X.homesec-1), which describes a security framework for identi-fying threats and the necessary security functions in the home network security model.

FIGURE 4.20

The Ethernet services delivery chain; reproduced with permission of the Metro Ethernet Forum

E-LAN & E-LINE Scalability PON Dynamic

Bandwidth Behavior UNI Services

Compliances

ONUs

High Availability via Spanning Tree

Protocols OLT

DSLAM

Ethernet Switches

MSPP

Edge Router

ADMs Service Interruption and

BER Measurements Access Network

Aggregation Network

Core IP & MPLS Network

Optical Transport Edge

Router

Ethernet Access

In the previous part of this book, we described networks. Here, we turn to processors and processing and discuss the theory behind network proces-sors. No specifi c network processors are described or mentioned, except when required as an example to clarify the theory.

This part begins with frame and packet processing, the algorithms used, data structures, and the relevant networking schemes required for packet processing. These include, for example, network addressing, classifi cation, and look-up schemes. It then describes Class of Service (CoS) and Quality of Service (QoS) schemes, and the way that the network, the equipment, and the chips handle packet traffi c accordingly (e.g., buffering and sche-duling packets along network paths).

After dealing with packet processing and handling algorithms, this part turns to processors themselves. It begins with hardware (architecture),

2

Processing

PART

moves on to software (programming models, languages, and development platforms), and concludes with network processors’ peripherals—devices that are usually adjunct to network processors.

This part contains the following chapters:

■ Chapter 5—Packet Processing

■ Chapter 6—Packet Flow Handling

■ Chapter 7—Architecture

■ Chapter 8—Programming Models

■ Chapter 9—Network Processors’ Peripherals

After the fi rst two parts, which examined the two terms of the title sepa-rately, in the third part we turn to integrating the two subjects, networks and processing, with a concrete example of a network processor.