Information and Communication Technology

Google and Partners Seek TV Foothold

2010-03-20T14:18:00.000+08:00

Google, Sony and Intel are teaming up to create set-top boxes.

The boxes would let users access Web applications like Twitter from their TVs.

Google will open the platform to developers. This could spur the development of apps like those on smartphones.

Click here to read more >>

South Korea to get 4G iPhone

2010-01-17T01:46:00.002+08:00

South Korea will get iPhone 4G in April as reported in The Korea Times.

The phone video will feature live chat and an OLED display. It could also have a removable battery, among other improvements.

WiMAX, which is 4G, is being installed in the United States.

StarHub's Nucleus Connect Selected As Singapore's Nationwide Next Gen NBN OpCo

2009-04-03T21:44:00.000+08:00

The Infocomm Development Authority of Singapore (IDA) announced the selection of StarHub's proposal for the Next Generation National Broadband Network Operating Company (Next Gen NBN OpCo) Request For Proposal.

Under its proposal, StarHub will establish the Next Gen NBN OpCo, called Nucleus Connect, to design, build and operate the active infrastructure. Nucleus Connect will deploy advanced technologies to support and enable a comprehensive range of ultra-high speed wholesale broadband services to Retail Service Providers, or RSPs, at competitive prices that will be regulated by IDA.

Nucleus Connect will, for example, offer a wholesale price of $21 per month for a 100 Mbps residential end-user connection and $121 for a 1Gbps connection. The Next Gen NBN NetCo and OpCo RFPs were structured to ensure that downstream operators have Effective Open Access to the Next Gen NBN. Nucleus Connect will be operationally separated from all RSPs.

What is Throughput?

2008-12-24T21:24:00.001+08:00

In communication networks, such as Ethernet or packet radio, throughput is the average rate of successful message delivery over a communication channel.

This data may be delivered over a physical link, over a wireless channel, or that is passing through a certain network node, such as data passed between two specific computers.

The throughput is usually measured in bits per second (bit/s or bps).

The system throughput or aggregate throughput is the sum of the data rates that are delivered to all terminals in a network.

Telstra challenges SingTel for Aussie deal

2008-11-27T22:13:00.003+08:00

Telstra Corp, Australia 's largest phone company, submitted a proposal to bid to build a nationwide high-speed Internet network in Australia, challenging the Terria group led by Singapore Telecommunications and two others.

Telstra, the former state-owned phone monopoly, aims to defend its dominance in Australia 's telecommunications market.

Second-ranked SingTel Optus Pty, SingTel's Sydney-based subsidiary which has less than a third of Telstra's high-speed Internet users, could narrow the gap by building the fibre-optic network.

What is ETSI?

2008-11-20T00:56:00.000+08:00

ETSI stands for European Telecommunications Standards Institute.

ETSI is an independent, non-profit organization, whose mission is to produce telecommunications standards.

ETSI is officially responsible for standardization of Information and Communication Technologies (ICT) within Europe. These technologies include telecommunications, broadcasting and related areas such as intelligent transportation and medical electronics.

What is Time Division Multiple Access (TDMA)?

2008-11-11T21:41:00.000+08:00

A communications technique whereby the total capacity of a transmission channel is shared among multiple users by alllocating each a unique time slot.

What is Time Division Duplex (TDD) and Frequency Division Duplex (FDD)?

2008-11-05T21:34:00.001+08:00

Time Division Duplex

A technology used in communications where the uplink and the downlink use the same frequency.

The uplink and downlink are separated in time. Users get one or more time slots assigned for the uplink and the downlink respectively. TDD makes it possible to dynamically allocate more bandwidth to downstream traffic if necessary. This makes TDD very bandwidth efficient in cases where the traffic flow is asymmetric.

In order to cater for the time needed by the data to travel from the source to the destination, a guard time is needed between the time slots assigned to the uplink and the downlink.

For the same reason, the distance between the user and the network may not be too big in a wireless network. Another disadvantage of TDD is that it introduces some delay within the network.

Frequency Division Duplex (FDD)

A technology used in wireless communications where the uplink and the downlink use a different frequency. The uplink and downlink are separated by a certain gap. This is called the duplex spacing.

FDD is very inefficient if the traffic pattern is asymmetric.

What is CIF / 4CIF?

2008-10-28T22:35:00.001+08:00

CIF: Common Intermediate Format.

It is used to standardize the horizontal and vertical resolutions in pixels of a video signal.

FORMAT        NTSC              PAL

CIF                   352 x 240         352 x 288

4CIF                 704 x 480         704 x 576

What is Ethernet, Fast Ethernet, Gigabit Ethernet?

2008-10-20T00:27:00.000+08:00

Ethernet

Ethernet (IEEE 802.3) is an international standardized network technology that enables computers to communicate with each other in a Local Area Network (LAN).

A simple Ethernet consists of a number of workstations (nowadays mostly Personal Computers) that are attached to a single large cable system, called the Ethernet bus or the trunk. This trunk is shared among all the attached workstations. It is also possible to connect a hub to the bus. Individual workstaton can be attached to the hub in a star-like manner. Ethernet supports a data transfer rate of 10 Mbps.

Fast Ethernet

A newer version of Ethernet, called Fast Ethernet, supports data transfer rates of 100 Mbps.

Gigabit Ethernet

Gigabit Ethernet supports rates of 1,000 Mbps (1 Gbps). This version is mainly used as a backbone to interconnect different LANs.

Gigabit Ethernet can use different types of cable.

1000Base-LX
Long wavelength laser (1300 nm) optical fibres.
Maximum cable length is 316 m in a half-duplex configuration and 550 m in a full-duplex configuration.
Can be extended to 5000 m if a very thin (10 µm) single mode fiber is used.

1000Base-SX
Short wavelength laser (850 nm) multi-mode optical fiber.
Maximum cable length is 275 m on a 62.5 µm fiber cable.
With a 50 µm fiber cable a length of 316 m in a half-duplex configuration or 550 m in a full-duplex configuration can be reached.

1000Base-T

Four pairs of 100 Ohm unshielded twisted pair, category 5.

Maximum cable length is 100 m.

1000Base-CX
Shielded twisted pair.
Maximum cable length is 25 m.

Gigabit Ethernet is defined in IEEE 802.3z and 802.3ab (1000Base-T).

The latest version of Ethernet can even handle data rates of 10 Gbps. The 10 Gigabit Ethernet version is defined in IEEE 802.3ae

Will cloud computing transform IT?

2008-10-12T17:15:00.000+08:00

Technology allows access to seemingly limitless power, storage

By ANDREA JAMES
P-I REPORTER

For a business, the electricity that flows from an outlet seems endless. And water will stream out of the tap without worry -- businesses pay only for what they use.

· Firms fueled by cloud computing

But computing power hasn't been so seamless. Data storage hardware can accept only a finite number of bytes. When businesses enter into monthlong server contracts, it takes days to add more capacity. If usage surpasses a server's capacity, it will crash.

Cloud computing, the super-hyped tech term of the moment, aims to change that.

Cloud computing, utility computing, Web 3.0 and grid computing are all jargon to describe a simple concept: Access to seemingly limitless computing power and storage space via the Internet.

If you use Google's Gmail service for e-mail, you've touched the cloud.

As of Monday, millions of Gmail users had 7,045 free megabytes of e-mail space each -- more than enough to store more than 7 million plain text e-mails.

That's the triumph of cloud computing. The downside, however, was illustrated one day last week when Gmail suffered an outage, and millions temporarily lost access to their e-mails.

Read more here.

What is Simplex, Semi Duplex, Full Duplex?

2008-10-10T21:10:00.002+08:00

Simplex

A radio communications technology that allows only one way communication at any one time. The operating frequency is either used for listening or for talking. e.g Walkie Talkie.

Semi Duplex

A semi duplex in radio communications is transmission one way at the time (either listening or talking) and the uplink and downlink operate on two different frequencies. It is a special case of simplex operations. e.g TETRA group communication.

Full Duplex

A full duplex in radio communications is transmission in both directions at the same time is possible. e.g Mobile telephone service.

Both directions can be separated in time or in frequency. This is called Time Division Duplex (TDD) and Frequency Division Duplex (FDD) respectively.

What is RFID?

2008-09-30T00:02:00.000+08:00

RFID stands for Radio-Frequency IDentification.

RFID refers to small electronic devices that consist of a small chip and an antenna.

The RFID device serves the same purpose as a bar code on your purchase. It provides a unique identifier for that purchase. Similarly, the RFID device must be "scanned" to retrieve the identifying information.

RFID devices will work within a few feet of the reader. For example, you could just put all of your purchase from supermarket in a bag, and set the bag on the reader. The reader would be able to query all of the RFID devices and total your purchase immediately.

However, system must be set-up carefully to avoid reader collision. Reader collision occurs when the signals from 2 or more readers overlap.

What is Spectral Efficiency?

2008-09-27T22:02:00.000+08:00

Spectral efficiency refers to the amount of information that can be transmitted over a given bandwidth in a specific communication system.

Hong Kong traffic surveillance system migrates to IP Video

2008-09-27T14:28:00.000+08:00

Like many large analog systems, Hong Kong’s CCTV surveillance consists of a number of isolated video control rooms which are not interconnected to form a single centrally monitored system – often referred to as ‘islands’ of video. IndigoVision’s IP-CCTV technology has been used to extend the capabilities of Hong Kong’s extensive traffic surveillance system.

The current analog system has been expanded with the addition of 48 cameras using IndigoVision’s IP Video system, creating a fully integrated 250 camera hybrid solution. The introduction of IndigoVision’s IP-based distributed network provides a platform for full migration to IP Video in the future.

The migration project was designed and installed by IndigoVision’s local partner Tung Po (HK) Technology Enterprise Ltd. Tung Po also developed bespoke software to create an integrated ‘front end’ for both the existing analog system and IndigoVision’s IP Video. This was interfaced with ‘Control Center’, IndigoVision’s IP Video and alarm management software, which provides powerful virtual matrix switching features, alarm handling and video analysis tools.

The IndigoVision solution has created a scalable and distributed solution that will allow the future integration of these remote control rooms into one unified system, allowing Hong Kong’s Traffic Police to centrally manage and control the region’s traffic problems.

Plans are in place to expand the system to over 700 cameras. The first phase of this expansion has been completed with the addition of a 48 camera IP-based system to monitor the Northern district of the city, which was previously not monitored. This region is close to the Chinese border and has significant traffic problems caused by 2 million people a day making cross border journeys. Even though the new extension to the system is predominantly for traffic surveillance the Police also use it for monitoring public events in the area. This demonstrates how easy additional monitoring can be integrated into the new system – something that would have been too costly with analog CCTV equipment.

IndigoVision’s IP Video solution provides a number of significant benefits compared to old VCR/analog systems. Multiple live camera views can be displayed alongside recorded video on the same monitor. ‘Control Center’ tools provide fast analysis of recorded footage allowing the Traffic Police to quickly determine the cause of accidents and incidents. Cameras can also be easily added or relocated in response to changes in the traffic situation at specific locations.

“IndigoVision’s system was chosen following an analysis of competing systems,” said Mr. Kenny Leung of Tung Po (HK). “The equipment easily exceeded the technical compliance part of the tender and the end-user was particularly impressed with the picture quality and low latency. Operators can smoothly control PTZ on cameras that are located in the Northern District over 15 miles away.”

IndigoVision’s Software Interface Kit (SIK) was used to develop an interface for uploading video images to the Traffic Department’s website, allowing the public to view selected traffic cameras. IndigoVision uses the SIK to develop interfaces for many third party systems including access control systems, to create a truly integrated solution for IP security applications.

The combination of ‘Control Center’ and the IP network creates a ‘virtual matrix’. This replaces the physical video switching matrices of analog systems. Each of the analog camera feeds are connected to IndigoVision’s 8000 transmitter/receiver modules, which converts the signal to 4CIF 25 fps digital video for transmission over the network. The ‘virtual matrix’ can switch any camera feed to any PC or Monitor, wherever they are located on the IP network. Seven days of full-frame rate continuous video is recorded using IndigoVision’s Windows Network Video Recorder (NVR) software running on dual-redundant servers located at the Transport Department HQ.

Article taken from www.securitypark.co.uk

OpenNet to provide passive fibre grid services for Singapore's Next Generation National Broadband Network

2008-09-26T23:16:00.000+08:00

OpenNet has been selected to provide passive fibre grid services for Singapore's Next Generation National Broadband Network (NGNBN) and will be expected to complete by June 2012.

The OpenNet consortium expects to spend around S$2 billion over the 25-year license period for access to infrastructure.

The OpenNet consortium is composed of Singapore Telecommunications Limited (30%), Axia NetMedia Corporation (30%), Singapore Press Holdings Limited (25%) and SP Telecommunications Pte Ltd (15%).

Construction of the infrastructure will utilize existing underground ducts from SingTel.

The NGNBN paves the way for an advanced broadband infrastructure, which will boost Singapore's competitiveness and attractiveness as a global business and infocomm hub.

Singapore will experience faster and better broadband access than ever before to harness the full power of the internet.

What is SIL1, SIL2, SIL3, SIL4?

2008-09-22T21:35:00.001+08:00

Safety Integrity Level (SIL) is a measurement of performance required for a Safety Instrumented Function (SIF).

SIL is defined as a relative level of risk-reduction provided by a safety function, or to specify a target level of risk reduction.

Four SIL levels are defined, with SIL1 being the least dependable and SIL4 being the most dependable.

What is API?

2008-09-01T23:24:00.000+08:00

API, Application Programming Interface is a set of declarations of the functions that an operating system provides to support requests made by computer programs.

Language-dependent APIs are available only in a particular programming language. They utilize the syntax and elements of the programming language to make the API convenient to use in this particular context.

Language-independent APIs are written in a way that means they can be called from several programming languages. This is a desired feature for a service-style API which is not bound to a particular process or system and is available as a remote procedure call.

What is TETRA Gateway Mode?

2008-08-30T22:09:00.000+08:00

TETRA gateway mode refers to a single mobile with connection to the network can act as a relay for other nearby mobiles that are out of range of the infrastructure.

What is Guard Band?

2008-08-27T21:41:00.000+08:00

Guard Band is an unused narrow frequency range between 2 wider frequency range to prevent overlapping/interference.

It is used to separate the 2 frequency ranges to ensure that both can transmit simultaneously without interfering each other.

OSI Model Layers with Examples

2008-08-25T21:51:00.000+08:00

Layer 7: Application e.g HL7, Modbus.

Layer 6: Presentation e.g TDI, ASCII, MIDI, MPEG.

Layer 5: Session e.g NetBIOS, SAP, Half Duplex, Full Duplex, Simplex.

Layer 4: Transport e.g nanoTCP, nanoUDP.

Layer 3: Network e.g Q.931.

Layer 2: Data Link 802.3 (Ethernet), 802.11a/b/g/n MAC/LLC, 802.1Q (VLAN), ATM, FDDI, Fibre Channel, Frame Relay, PPP, Q.921, Token Ring.

Layer 1: Physical e.g RS-232, T1, E1, 10BASE-T, 100BASE-TX, SDH,DSL, 802.11a/b/g/n PHY.

NEC to provide Mobile WiMAX for Thailand’s Crown Prince Hospital Foundation

2008-08-24T23:04:00.001+08:00

NEC Corporation is selected to provide WiMAX systems to medical facilities located in Thailand's northern Chiang Khong region. Thailand's Crown Prince Hospital Foundation has more than twenty domestic hospitals throughout the country.

In January 2008 trial licenses were issued to 12 communications carriers in order to introduce WiMAX service nationwide. As efforts to promote broadband expansion outside of Bangkok progress, expectations for WiMAX wireless broadband infrastructure is on the rise. Early indications show that despite regional constraints and usage limitations, demand for WiMAX access, beyond large scale services, currently exists. NEC regards its WiMAX services for Chiang Khong medical care as part of the expansion of local demand.

The Chiang Khong hospital WiMAX services will provide wireless broadband communications to locations within a maximum of five kilometers and expands communications beyond fixed analog telephone lines to include new video and TV phone services that can assist with remote medical care.

The efficiency of daily medical care will be improved by granting doctors access to high speed transmission for large capacity data, including images and information.

In terms of Asian development, NEC began participating in Taiwan based WiMAX system trials in 2007, which resulted in an order for services from Tatung InfoComm in December of the same year.

Taiwan's movement towards becoming a highly information-oriented society has placed the country in a leadership position in the advancement of global WiMAX expansion.

What is telematics?

2008-08-21T22:10:00.000+08:00

A simple definition is that telematics is the term given to the technology that enables remote access to vehicle data over a wireless network.

In short, telematics refers to the integration of wireless communications and computing, sending, receiving and storing information via telecommunication devices.

More specifically, the integrated use of telecommunications and informatics, also known as ICT (Information and Communications Technology).

These devices allow drivers to browse the Internet, send and receive e-mails, receive live traffic updates, listen to satellite radio, and perform various other activities.

More commonly, telematics have been applied specifically to the use of Global Positioning System (GPS) technology integrated with computers and mobile communications technology in automotive navigation systems.

Most narrowly, the term has evolved to refer to the use of such systems within road vehicles, in which case the term vehicle telematics may be used.

What is MTBF?

2008-08-20T20:56:00.003+08:00

MTBF (Mean Time Between Failures) is a measure of how reliable a product is.

Define as the average amount of time, usually expressed in hours, that a electronic product such as a printer or amplifier is expected to work without failure.

Speeding up the Internet

2008-08-16T17:18:00.001+08:00

Metamaterials may help speed up the Internet. Light travels quickly on fiber-optic networks. But separating the light slows data transfer. Metamaterials could help by slowing parts of the light down.

The net's speed limit comes about not in transporting information, but in routing it to its various destinations.

As data nears the end of its journey, the bulky and slow electronics will do the routing and send them to their destinations.

Metamaterials could replace these electronics, thus paving the way for lightning fast speeds.

What is GPON?

2008-08-14T21:07:00.001+08:00

GPON (Gigabit Passive Optics Networks, ITU-T G.984) is an evolution of the BPON (Broadband PON) standard. It supports higher rates, enhanced security, and choice of Layer 2 protocol (ATM, GEM, Ethernet).

The GPON standard represents a boost in both the total bandwidth and bandwidth efficiency through the use of larger, variable-length packets. Again, the standards permit several choices of bit rate, but the industry has converged on 2.488 gigabits per second (Gbit/s) of downstream bandwidth, and 1.244 Gbit/s of upstream bandwidth.

GPON Encapsulation Method (GEM) allows very efficient packaging of user traffic, with frame segmentation to allow for higher Quality of Service (QoS) for delay-sensitive traffic such as voice and video communications.

A passive optical network (PON) is a point-to-multipoint, fiber to the premises network architecture in which unpowered optical splitters are used to enable a single optical fiber to serve multiple premises, typically 32-128.

A PON consists of a central office node, called an optical line terminal (OLT), one or more user nodes, called optical network units (ONUs) or optical network terminals (ONTs), and the fibers and splitters between them, called the optical distribution network (ODN).

The OLT provides the interface between the PON and the backbone network. These typically include:

* Internet Protocol (IP) traffic over Gigabit, 10G, or 100 Mbit/s Ethernet
* standard time division multiplexed (TDM) interfaces such as SONET/SDH or PDH at various rates

An ONT is a single integrated electronics unit that terminates the PON and presents native service interfaces to the user. In apartment buildings, the ONT often separately connects via VDSL or Ethernet to the apartments, at speeds up to 100 megabits.

A PON is a shared network, in that the OLT sends a single stream of downstream traffic that is seen by all ONTs. Each ONT only reads the content of those packets that are addressed to it. Encryption is used to prevent eavesdropping on downstream traffic.

What is DWDM?

2008-08-07T14:28:00.000+08:00

DWDM, Dense Wavelength Division Multiplexing, refers originally to optical signals multiplexed within the 1550-nm band so as to leverage the capabilities (and cost) of erbium doped fiber amplifiers (EDFAs), which are effective for wavelengths between approximately 1525 nm - 1565 nm (C band), or 1570 nm - 1610 nm (L band).

Today's DWDM systems use 50 GHz or even 25 GHz channel spacing for up to 160 channel operation.

DWDM systems have to maintain more stable wavelength or frequency than those needed for CWDM because of the closer spacing of the wavelengths. Precision temperature control of laser transmitter is required in DWDM systems to prevent "drift" off a very narrow frequency window of the order of a few GHz.

In addition, since DWDM provides greater maximum capacity it tends to be used at a higher level in the communications hierarchy than CWDM, for example on the Internet backbone and is therefore associated with higher modulation rates, thus creating a smaller market for DWDM devices with very high performance levels. These factors of smaller volume and higher performance result in DWDM systems typically being more expensive than CWDM.

Recent innovations in DWDM transport systems include pluggable and software-tunable transceiver modules capable of operating on 40 or 80 channels. This dramatically reduces the need for discrete spare pluggable modules, when a handful of pluggable devices can handle the full range of wavelengths.

What is Hub-and-Spoke model?

2008-07-30T12:18:00.001+08:00

The hub-and-spoke is a system of connections arranged like a chariot wheel, in which all traffic moves along spokes connected to the hub at the centre.The model is commonly used in industry, in particular in transport, telecommunications and freight, as well as in distributed computing.Spokes are simple, and new ones can be created easily.Because model is centralized, day-to-day operations may be relatively inflexible. Changes at the hub, or even in a single route, could have unexpected consequences throughout the network. It may be difficult or impossible to handle occasional periods of high demand between two spokes.

Singapore's Next Generation National Broadband Network (Next Gen NBN)

2008-07-26T22:10:00.001+08:00

Singapore's Next Generation National Infocomm Infrastructure comprises the ultra high-speed Next Generation NBN and the pervasive Wireless Broadband Network (WBN). Next Gen NBN will be capable of ultra high speeds of symmetric 1 Gbps or more, with initial provisioning of 100 Mbps.

The Network Company (NetCo) Request-For-Proposal (RFP) for Singapore's Next Gen NBN Network closed on 5 May 2008 with submissions from the following:

S/N	Consortium	Consortium Lead	Members
1	Infinity Consortium	City Telecom (H.K.) Limited	MobileOne Ltd StarHub Ltd
2	OpenNet Consortium	Axia NetMedia Corporation	Singapore Press Holdings Ltd Singapore Telecommunications Pte Ltd SP Telecommunications Pte Ltd

IDA of Singapore is evaluating the bids and the winning bid is expected to be announced in the third quarter of 2008.

Earthlink is dropping its citywide Wi-Fi

2008-07-22T20:37:00.000+08:00

Earthlink is dropping its citywide Wi-Fi project in Philadelphia. The network had many glitches and few subscribers. No one agreed to buy the network, so Earthlink will dismantle it. It is discontinuing its municipal Wi-Fi projects across U.S.A.

What is CWDM?

2008-07-20T14:20:00.000+08:00

CWDM stands for Coarse Wavelength-Division Multiplexing system in which four wavelengths near 1310 nm, each carrying a 3.125 gigabit(Gb)/second data stream, are used to carry 10 gigabit-per-second of aggregate data.

The main characteristic of the recent ITU CWDM standard is that the signals are not spaced appropriately for amplification by EDFAs. This therefore limits the total CWDM optical span to somewhere near 60 km for a 2.5 Gbit/s signal, which is suitable for use in metropolitan applications. The relaxed optical frequency stabilization requirements allow the associated costs of CWDM to approach those of non-WDM optical components.

CWDM is also being used in cable television networks, where different wavelengths are used for the downstream and upstream signals. In these systems, the wavelengths used are often widely separated, for example the downstream signal might be at 1310 nm while the upstream signal is at 1550 nm.

What is Metro E?

2008-07-16T13:42:00.001+08:00

Metro E stands for Metro Ethernet, is a computer network based on the Ethernet standard and which covers a metropolitan area. It is commonly used as a metropolitan access network to connect subscribers and businesses to a Wide Area Network, such as the Internet.

An Ethernet interface is cheaper than a SDH interface of the same bandwidth. Another advantage of an Ethernet-based access network is that it can be easily connected to the customer network, due to the prevalent use of Ethernet in corporate and, more recently, residential networks. Therefore, bringing Ethernet in to the Metropolitan Area Network (MAN) introduces a lot of advantages to both the service provider and the customer (corporate and residential).

A typical service provider Metro Ethernet network is a collection of Layer 2 or 3 switches or routers connected through optical fiber. The topology could be a ring, hub-and-spoke (star), full mesh or partial mesh. The network will also have a hierarchy: core, distribution and access. The core in most cases is an existing IP/MPLS backbone, but may migrate to newer forms of Ethernet Transport in the form of 10G or 100G speeds.

Ethernet on the MAN can be used as pure Ethernet, Ethernet over SDH, Ethernet over Multi Protocol Label Switching (MPLS) or Ethernet over Dense Wavelength Division Multiplexing (DWDM).

Pure Ethernet-based deployments are cheap but less reliable and scalable, and thus are usually limited to small scale or experimental deployments.

MPLS based deployments are costly but highly reliable and scalable, and are typically used by large service providers.

SDH-based deployments are useful when there is an existing SDH infrastructure already in place, its main shortcoming being the loss of flexibility in bandwidth management due to the rigid hierarchy imposed by the SDH network.

An SDH based Ethernet MAN is usually used as an intermediate step in the transition from a traditional, time-division based network, to a modern statistical network (such as Ethernet). In this model, the existing SDH infrastructure is used to transport high-speed Ethernet connections. The main advantage of this approach is the high level of reliability, achieved through the use of the native SDH protection mechanisms. On the other hand, an SDH-based Ethernet MAN is usually more expensive, due to costs associated with the SDH/DWDM equipment that is necessary for its implementation.

Traffic engineering also tends to be very limited. Hybrid designs use conventional Ethernet switches at the edge of the core SDH ring to alleviate some of these issues, allowing for more control over the traffic pattern and also for a slight reduction in cost.

What is WDM?

2008-07-10T14:09:00.000+08:00

In fiber-optic communications, wavelength-division multiplexing (WDM) is a technology which multiplexes multiple optical carrier signals on a single optical fiber by using different wavelengths (colours) of laser light to carry different signals. This allows for a multiplication in capacity, in addition to enabling bidirectional communications over one strand of fiber. "This is a form of frequency division multiplexing (FDM) but is commonly called wavelength division multiplexing.

Roam seamlessly between WiMAX and Wi-Fi network

2008-07-04T20:10:00.000+08:00

Green Packet Berhad, developer of next-generation mobile broadband and networking solutions and GCT Semiconductor, a supplier of mobile WiMAX solutions to the global market, have announced collaboration to bring the world’s first intelligent connection management solution. This solution is expected to provide connectivity and handover between WiMAX and Wi-Fi.

Malaysia’s first and largest WiMAX operator, Packet One Networks Sdn Bhd, has already been signed by Green Packet, which has its headquarters in Kuala Lumpur. Green Packet will look to roll out this new and innovative technology in Malaysia.

GCT’s GDM7215 single-chip WiMAX plus Wi-Fi integrated circuit offers benefits such as a physically smaller solution, lower power consumption and reduced bill-of-materials. Users can roam seamlessly between WiMAX and WiFi networks and create a robust and highly-desirable wireless broadband experience.

Fiber-optic broadband shows strong growth

2008-07-04T07:42:00.000+08:00

Fiber-optic broadband growth is overtaking cable.

With China showing the strongest growth. However, DSL is still the most popular form of broadband.

Data transfer speed of WiMAX technology for end users

2008-06-27T19:16:00.000+08:00

Users can expect to have broadband access speeds ranging from 1-5 Mbps depending on the service provider offering.

When the WiMAX Forum refers to 40 Mbps, it is referring to a single channel in wireless frequency (as part of the network) that is likely shared among multiple users. Individual users will have access to that amount of capacity, but the likelihood is they will have the ability to achieve downlink speeds of 1-5 Mbps, which is similar to the cable experience. There is the potential to burst to higher speeds, but that would depend on the operator's plans and business model, frequency being used, distance of the user from the base station or node, whether there is line of site or NLoS to the base station, and the number of users on the network.

A single WiMAX base station or node should be able to serve thousands of subscribers. The actual number of users will depend on the guaranteed bandwidth to each users and the actual spectrum used by the operator.

Skype focuses on video

2008-06-20T08:34:00.000+08:00

Skype begin public testing of its new software. Video will be a more integral part of Skype 4.0. The company hopes to encourage more people to use video chat. Skype routes phone calls over the Internet. It offers free and paid plans.

Verizon boosts FiOS speeds

2008-06-19T08:32:00.001+08:00

Verizon’s FiOS fiber-optic broadband is getting a speed boost in 10 states in U.S.A. Verizon has already boosted FiOS speeds in other areas. The fastest service provides 50Mbps downloads and 20Mbps uploads for $140 monthly.

What is Wi-Fi?

2008-06-07T11:57:00.005+08:00

Wi-Fi, Wireless Fidelity, is way to get Internet access and used to define any of the wireless technology in the IEEE 802.11 specification - including (but not necessarily limited to) the wireless protocols 802.11a, 802.11b, and 802.11g.

The Wi-Fi Alliance is the body responsible for promoting the term and its association with various wireless technology standards. is meant to be used generically when referring of any type of 802.11 network.

Any products tested and approved as "Wi-Fi Certified" (a registered trademark) by the Wi-Fi Alliance are certified as interoperable with each other, even if they are from different manufacturers.

The Wi-Fi Alliance began as a community aiming to address the needs of consumers by ensuring products from different vendors working well together. The Alliance created the branding "Wi-Fi Certified" to reassure consumers that products will interoperate with other products displaying the same branding.

However, any Wi-Fi product using the same radio frequency (for example, 2.4GHz for 802.11b, 802.11g, 5GHz for 802.11a) will work with any other, even if not "Wi-Fi Certified."

A Wi-Fi enabled device can connect to the Internet when within range of a wireless network connected to the Internet. The coverage of one or more interconnected access points — called a hotspot — can comprise an area as small as a single room with wireless-opaque walls or as large as many square miles covered by overlapping access points.

Wi-Fi also allows connectivity in peer-to-peer (wireless ad-hoc network) mode, which enables devices to connect directly with each other. This connectivity mode can prove useful in consumer electronics and gaming applications.

Wi-Fi technology boasts fast data transfer speeds and range, making it a good replacement for Ethernet (802.3) systems.

Key elements of WiMAX technology

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A key differentiator for WiMAX is the interoperability of WiMAX Forum Certified equipment, resulting in mass volume economy of scale and assurance for service providers that when buying equipment from more than one company, the technologies are interoperable.

The WiMAX Forum has assembled an alliance of leaders in the communications and computing industries to drive a common platform for the global deployment of IP-based broadband wireless services. Other key elements include cost, coverage, capacity and standards for both fixed and mobile wireless usage models.

Lower cost

A standards based platform for WiMAX technology drives down costs delivering volume economics to WiMAX equipment.

Wider coverage

The technology behind WiMAX has been optimized to provide excellent non-line-of-sight (NLoS) coverage. NLoS advantages are coverage of wider areas, better predictability of coverage and lower cost as it means fewer base stations and backhaul, simple RF planning, shorter towers and faster CPE install times. Thanks to techniques for improving NLoS coverage, such as diversity, space-time coding, and Automatic Retransmission Request (ARQ), coverage are increased.

Higher capacity

A key advantage of WiMAX technology is to use Orthogonal Frequency-Division Multiplexing (OFDM) over Edge, GPRS, HSPA to deliver higher bandwidth efficiency and therefore higher data throughput, with more than one Mbps downstream and higher data rates. Adaptive modulation also increases link reliability for carrier-class operation and the possibility to keep higher order modulation at wider distance extend full capacity over longer distances.

Standard for all usage models (fixed to mobile)

By leveraging the same technology networks, WiMAX technology will become the most cost-effective solution for carriers to deploy for any usage model from fixed to mobile.The WiMAX Forum certifies products for conformance and interoperability based upon the standards IEEE 802.16.

Broadband connectivity examples:

High speed internet access where it is currently unavailable
Substantially increase data speeds for applications to include online gaming, streaming video, video conferencing, VoIP and location based services
Drive wireless Internet equipment and access prices to a competitive price point comparable to cable, DSL, and fiber Internet services
With a robust telecommunications infrastructure already in place in the U.S. Mobile WiMAX services from Sprint and Clearwire will reach more than 150 million consumers by year end 2008.
In Australia, WiMAX technology will establish an affordable and efficient broadband network. This wireless broadband technology is perfectly suited for regional and rural areas and the purchase and installation process of WiMAX technology is faster, simpler and cheaper than other offered solutions. Additionally, the non-line-of-sight (NLoS) capability means that WiMAX technology can provide coverage despite the challenges of geography and the limited footprint of wireline.
Taiwan has continued its leadership in the development and deployment of WiMAX operability with six commercial WiMAX licenses awarded in July 2007 for six separate Taiwanese wireless communication providers. In regions like Taiwan, where users are spread out and the wireless traffic is going a long distance, WiMAX technology provides a reliable, inexpensive solution for constant wireless broadband connectivity.
In Africa as a developing continent, WiMAX technology provides the opportunity to connect the African people with Internet and VOIP services faster and more affordably than wireline.

WiMAX Technology

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WiMAX, the Worldwide Interoperability for Microwave Access, is based upon the IEEE 802.16 standard enabling the delivery of wireless broadband services anytime, anywhere.

WiMAX products can accommodate fixed and mobile usage models. The IEEE 802.16 standard was developed to deliver non-line-of-sight (LoS) connectivity between a subscriber station and base station with typical cell radius of 3 to 10 kilometers.

All base stations and subscriber stations claiming to be WiMAX compliant must go through a rigorous WiMAX Forum Certified testing process.

As the exclusive organization dedicated to certifying the interoperability of products based upon IEEE 802.16/ETSI Hyperman, the WiMAX Forum defines and conducts conformance and interoperability testing to ensure that different vendor systems work seamlessly with one another. Those that pass conformance and interoperability testing will receive the WiMAX Forum Certified designation.

Vendors claiming their equipment is “WiMAX-like,” WiMAX-compliant,” etc., are not WiMAX Forum Certified, which means that their equipment is not independently certified to be interoperable with other vendors’ equipment and operators are encouraged to be wary of this type of claim. Only look at the Wi-Fi claims of 802.11n to understand the potential problem should an operator who purchases WiMAX like products from one vendor and decide to switch to another vendor. Only WiMAX Forum Certified equipment is proven interoperable with other vendors’ equipment that is also WiMAX Forum Certified.

WiMAX Forum Certified systems can be expected to deliver capacity of up to 40 Mbps per channel. This is enough bandwidth to simultaneously support hundreds of businesses with T-1 speed connectivity and thousands of residences with DSL speed connectivity.

The WiMAX Forum expects mobile network deployments to provide up to 15 Mbps of capacity within a typical cell radius of up to 3 kilometers. WiMAX technology already has been incorporated in notebook computers and PDAs to deliver high speed mobile Internet services anytime, anywhere.