PROTOCOLS AND NETWORK CONFIGURATION

Protocols of Broadband

Broadband or Broadband Internet Access refers to high speed Internet access, and is one of the most popular of WAN protocols due to its high data transmission rate. Broadband can yield speeds of 256 kbit/s or more. Digital Subscriber Line (DSL) and cable modems are the standard broadband technologies used in a majority of areas. Newer technologies that have evolved include Very High Bitrate DSL (VDSL or VHDSL) and fiber-optic cables. DSL is based on modem technology for Internet access over copper telephone lines. Multiple DSL users are connected to the high-speed network using a Digital Subscriber Line Access Multiplexer (DSLAM). The telephone company employs the DSLAM to effectuate aggregation of data transmission from available DSL lines and then interconnecting them to the ATM network. At the transmission end point, a DSLAM forwards data to a DSL connection after demultiplexing the signals.

The different types of DSL connections (ADSL, HDSL, SDSL, IDSL and VDSL), collectively referred to as xDSL, establish connectivity between the telephone company and office. Digital Subscriber Lines use several modulation technologies: Discrete Multitone Technology (DMT), Simple Line Code (SLC), Carrierless Amplitude Modulation (CAP), Multiple Virtual Line (MVL), and Discrete Wavelet Multitone (DWMT).

Integrated Services Digital Network (ISDN), the basic network system of early WAN protocols, provides digitized phone connectivity and enables high speed transmission of voice, data, video and graphics across standard communication lines at the same time through bearer channels. ISDN can be transmitted through packet switched networks, and other types of networks besides telephone networks. ISDN service comprises two basic types, namely basic Rate Interface (BRI) and Primary Rate Interface (PRI). While BRI contains a total 160 kb/s for use of individual users, PRI offers a total of 1536 kb/s and is designed for users who require more capacity, such as large Enterprises.

Protocol Used in Baseband

ISO 18000-6B UHF Protocol

SO 18000 is a suite of international standards established by the International Organization of Standardization (ISO) to support the development and integration of Radio Frequency Identification (RFID) tags. ISO 18000-6B UHF is an individual standard within this suite designed to support a given communication protocol.

Identification

RFID tags are used in supply chain management and logistics applications where companies tag shipments with RFID tags for identification. Using an RFID reader, distribution personnel or systems can identify the shipment and route it as applicable. To function, both the RFID tag and the RFID reader must operate to the same communications protocol. ISO 18000-6B UHF protocol is one such communications protocol.

Function

The ISO 18000-6B UHF communication protocol is defined by three unique characteristics: air interface, which identifies the modulation of the reader signal, medium access control, which controls the flow of information between the tag and the reader, and data definition, which identifies the type of data associated with a tag.

Significance

There are many RFID tags and associated communications protocols and many different readers. If the readers and the associated tags don't use the same protocol, this will significantly impede the transfer of goods throughout the distribution system. For this reason, companies must communicate and coordinate up and down the supply chain to ensure compatibility.




Network Topology of Baseband

Baseband Coaxial Cable

•         Baseband - digital signaling, bidirectional propagation

•         Ethernet with baseband - basis for IEEE 802.3

•         trade-of - data rate, cable length, number of taps

•         repeaters to extend network - different from ring’s repeaters, transparent to network stations

Network Architecture of Broadband

Network Algorithms of Broadband

The standard algorithm for computing the soft-inverse of a finite-state machine [i.e., the soft-in/soft-out (SISO) module] is the forward-backward algorithm. These forward and backward recursions can be computed in parallel, yielding an architecture with latency ��(N), where N is the block size. We demonstrate that the standard SISO computation may be formulated using a combination of prefix and suffix operations. Based on well-known tree-structures for fast parallel prefix computations in the very large scale integration (VLSI) literature (e.g., tree adders), we propose a tree-structured SISO that has latency ��(log₂N). The decrease in latency comes primarily at a cost of area with, in some cases, only a marginal increase in computation. We discuss how this structure could be used to design a very high throughput turbo decoder or, more generally, an iterative detector. Various sub windowing and tiling schemes are also considered to further improve latency.

Baseband Network Architecture

- A dual-processor architecture is needed to handle all the features in 3G/3.5G handsets.

In a data-flow example, voice and multimedia data is received on the antenna connected to the baseband processor and this data is then packetized and sent to the application processor. The application processor either stores the multimedia content in a file system or displays/plays it in real time. The interconnect bandwidth between the baseband and application processors can become a bottleneck in next generation 3G/3.5G wireless mobile handsets.

Baseband Network Algorithm

Digital transmission is the sending of information over a physical communications media in the form of digital signals. Analogue signals must therefore be digitized first before being transmitted.

This transformation of binary information into a two-state signal is done by the DCE, also known as the base band decoder, which is the origin of the name base band transmission to designate digital transmission.