A standard connection is charged by amount of data transmitted. The bandwidth you are allocated depends on terminal type and network availability, but is always `best effort¿, that is, you are allocated bandwidth depending on your requirements and the requirements of other users of the BGAN network, or BGAN terminal. This connection class is suitable for most data types, other than multimedia.
A Traffic flow template, also called an application template, is a series of data filters such as CoS (Class of Service), PDP context and security settings, that allow the GPRS core network to classify packets received from an external network into the correct PDP context. When incoming data arrives at an access point in the core network, a packet classifier will make a PDP context selection based on the traffic flow template, and map the incoming data packets into the PDP context with the correct CoS attributes. The use of a traffic flow template allows multiple PDP contexts to be associated with the same PDP address.
Wireless Networking
The Dawn of the Wireless Renaissance It’s Time to Go Wireless!
Although we’re constantly hearing about the miracle of wireless technology, we’re merely at the dawn of the Wireless Renaissance. From Auckland New Zealand to Mt. Everest, Internet cafes and other wireless hot spots dot our increasingly interconnected globe (yes, there really is an Internet Café at a Mt. Everest base camp), but the best and most ingenious use of this breakthrough innovation is yet to come. For now, the wireless gold standard is 802.11g – – the newest, fastest and most powerful 802.11 radio technology that broadens bandwidths to 54 Mbps within the 2.4 GHz band. Because of backward compatibility, older and slower 802.11b radio cards can interface directly with an 802.11g access point and vice versa at 11Mbps or lower, depending upon range. We’ve come a long way, baby – just in the past couple of months. That’s how rapidly the wireless net that will someday encompass the entire globe is morphing. Much quicker than we write these words, technicians are gleaning new ideas that will revolutionize the way we communicate. From Marconi (the inventor of wireless communication back in the late 19th Century) to 802.11g – the sky is not the limit for how far we will take the wireless renaissance – it was merely a suggestion that we rejected long ago.
Rating the 802.11 Wireless Standards In 1997, when the Institute of Electrical and Electronics Engineers (IEEE) created the first WLAN standard they called it 802.11. Because it could only support a maximum bandwidth of 2Mbps – far too slow for most of today’s applications – ordinary 802.11 wireless products are no longer being manufactured. The next wireless incarnation was 802.11b, which supports bandwidths of up to 11Mbps, followed by the creation of 802.11g, which supports bandwidth up to 54 Mbps and signals in a regulated 5 GHz range. While 802.11g is the fastest wireless technology, is it the best for your home or business? Here is a brief synopsis of the three primary 802.11 standards:
The Evolution of 802.11 Wireless Technology
Why Connect? According to International Data Corp. (IDC), about half of all U.S. households have a computer, and a much higher percentage of businesses use PCs. Tens of millions of these homes and businesses have more than one computer one. In fact, market research shows that current PC owners buy most of the new computers. This means that multi-computer households are becoming increasingly more common. If you are one these multiple-PC owners, you have probably thought about how great it would be if your computers could talk to each other. With your computers connected, you could:
Advantages of wireless networking:
It’s fast (11 – 108Mbps). It’s reliable. It has a long range (5,000 feet in open areas, 250 to 400 ft / 76 to 122 m in closed areas) It’s easily integrated into existing wired-Ethernet networks. Virtually all 802.11g wireless networking products work with each other no matter what brand or model. Wireless offers Ethernet speeds without the wires. Access points vary greatly in cost, from about $59.99 to $1,400. Access points have an integrated Ethernet connection to connect to an existing wired-Ethernet network or routers provide connectivity to a high-speed data connection (DSL or cable modem). It also has an omni-directional antenna to receive the data transmitted by the wireless transceivers. Integrating PCs and Apple systems on the same network is also possible with the 802.11g standard. The majority of wireless network adapters used are in PCMCIA card form. But some manufacturers do offer USB adapters or PCI format cards. The cost per card ranges from $39 to more than $300. They are not typically sold in “do-it-yourself” kits. Instead, everything is a la carte, allowing customers to build a system that exactly meets their needs.
For businesses, the benefits of wireless technology are dramatic; we are not using hyperbole when we assure you that it will revolutionize your company. A wireless infrastructure makes it easier for you to adapt your office space as your company evolves. And the productivity gains you will reap dwarf the relatively inexpensive cost of setting up a wireless local area network (LAN). Here are the primary benefits your business will receive by going wireless:
It’s Not as Complicated as You Think! Most people think that networking your home or small office can be painful, with lots of wires, connections and other challenges. Plus, you have to make everything talk to each another. Don’t fret, because it’s not as much of a challenge as you might think. With most people using Microsoft Windows operating systems, networking has been built-in since Windows 3.11. Introduced in Windows 98, “Internet Connection Sharing” is a standard part of the operating system, allowing one computer to share an Internet connection with all computers on the home network. So, if you are running Windows, you can share files, printers and resources across your network without too much of a hassle. Following are 3 easy steps that will allow even a novice to setup a wireless network.
Wireless Networking Made Simple 3 Easy Set Up Steps Even the Novice Can Master
1. Plan Your System – Before you dive into the wireless world, make sure you know what lies ahead of you. Make a thorough analysis of your networking needs, what you need to accomplish, and what you expect to receive as a reasonable return on your investment. Assess your networking needs; determine how many workstations you’ll need to connect and where you can best utilize them. Also, take an inventory of what upgrades you will have to make to your existing computer equipment and decide what equipment you will need to purchase. These are the types of devices required for your wireless network:
2. Setting Up Your System – Now that you have a plan in place that defines exactly what your equipment needs will be, how you will configure your network and what goals you expect to accomplish with wireless technology, it’s time to set up your network. Before you take this step (don’t worry, it’s much easier than it seems), you must develop a good working understanding of the equipment involved in a wireless network. Wireless LAN equipment consists of wireless clients – the notebook computers, printers or handheld devices that can communicate over a wireless LAN – and access points, which are the points that accept the wireless radio signals and then connect the LANs. Your access point is the central communications point for your computers. These Now it’s time to build the wireless LAN! Again, don’t panic – you will be amazed how simple it is. Here is what you have to do:
3. Implement security measures to protect the integrity of your wireless network – Remember, wireless communications transmit through the air rather than over a closed capable. Therefore, maintaining security over your system requires measures that are specific to wireless. Wireless security solutions include Media Access Control (MAC), WEP encryption and Traditional VPN (Virtual Private Network) securities controls. Following are brief summaries of these solutions:
Three simple steps – that’s all it takes to join the wireless revolution – along with a relatively small investment in new technology that you will recoup many times with your exponentially improved efficiency and streamlined operation. We have the expertise, incomparable product line and unparalleled pricing to help you become experience all the advantages of benefits of wireless technology.
A concentrated area offering coverage within the global footprint for particular regions in the world.
Stands for “Public Switched Telephone Network” which is the infrastructure that carries public telephone service across the globe.
A virtual private network (VPN) enables remote offices or users to gain secure access to their organization’s network over the public telecommunications network. This provides the benefits of remote access without the expense of dedicated leased or owned lines. VPNs work by using tunneling protocols, such as L2TP, to encrypt data at the sending end, and decrypt the data at the receiving end. This “tunnel” cannot be accessed by data that is not properly encrypted.
Your Distribution Partner supplies you with a subscriber identification module (SIM) Card or a Universal Mobile Telecommunications System Subscriber SIM (USIM) card. A SIM or USIM Card is a card commonly used in a GSM phone. The card holds a microchip that stores information and encrypts voice and data transmissions, making it extremely difficult to listen in on calls. The USIM card also stores data that identifies the caller to the Distribution Partner.
The rate at which streaming data is transmitted, in kilobytes per second (kbps). This rate applies to transmitted (uplink) and received (downlink) data. Desired symmetrical rate – From the drop-down list, choose the desired data rate for your Streaming connection. This can be 32kbps, 64kbps, 128kbps or 256kbps. This figure is guaranteed, unless the connection cannot meet this requirement because of bandwidth restrictions. In this case the rate defaults to the minimum symmetrical rate. Minimum symmetrical rate – From the drop-down list, choose the minimum data rate that you are prepared to accept for your Streaming connection. This can be 32kbps, 64kbps, 128kbps or 256kbps. This rate must be lower than the desired symmetrical rate. If the connection cannot meet this requirement, an error message displays.
A streaming connection is charged by time. You are charged for the amount of time the connection is active. Streaming enables multimedia data, such as video, to be sent in a continuous data stream and converted into sound and pictures. The bandwidth required for a streaming connection is difficult to predict, and depends on factors such as length of connection and number of receivers.
Class of Service (CoS) assigns a level of priority to certain types of data traffic, in particular high bandwidth applications such as video and multimedia. CoS attempts to maintain a guaranteed throughput level, and minimize error rates and end-to-end latency, so providing a higher level of service than “best effort” protocols.
Your Service Provider supplies you with a Subscriber Identification Module (SIM) Card or a Universal Mobile Telecommunications System Subscriber SIM (USIM) Card. A SIM or USIM Card is a card commonly used in a GSM phone. The card holds a microchip that stores information and encrypts voice and data transmissions, making it extremely difficult to listen in on calls. The USIM Card also stores data that identifies the caller to the Distribution Partner.
An Internet Protocol address, or IP address, is a number that identifies the computer that is sending or receiving information transmitted over the Internet. An IP address is made up of four groups of numbers between 0 and 255, separated by periods. For example, 207.115.79.4 is an IP address. In the BGAN system, IP addresses can be dynamic or static. Dynamic IP Address – A dynamic IP address is a temporary address that is assigned by your Internet Service Provider (ISP) when you connect to the Internet. If you do not need a permanent IP address, Inmarsat recommends that you obtain a dynamic IP address. Normally, individual users of the Internet use a dynamic IP address. Static IP Address – A static IP address is assigned permanently, and is used every time you connect to the Internet. Normally, companies and other organizations that have their own networks use static IP addresses.
A Serving GPRS Support Node (SGSN) It is responsible for the delivery of data packets from and to the mobile stations within its geographical service area. Its tasks include packet routing and transfer, mobility management (attach/detach and location management), logical link management, and authentication and charging functions. The location register of the SGSN stores location information (e.g., current cell, current VLR) and user profiles (e.g., IMSI, address(es) used in the packet data network) of all GPRS users registered with this SGSN.
Gateway GPRS Support Node. (GPRS stands for General Packet Radio Services) . A GPRS Core Network provides mobility management, session management and transport for Internet Protocol packet
services in GSM and WCDMA networks. The core network also provides support for other additional functions such as billing and lawful interception. It was also proposed, at one stage, to support packet radio services in the US D-AMPS TDMA system, however, in practice, most of these networks are being converted to GSM so this option is becoming largely irrelevant. Like GSM in general, GPRS is an
open standards driven system and the standardization body is the 3GPP.
An Access Point Name (APN) identifies an external network that is accessible from a terminal. An APN has several attributes associated with it that define how you can access the external network at that point. By default, the SIM card in your terminal is configured with the APN of your Service Provider. You may want to configure further APNs if you have arranged with your Service Provider to use more than one SIM Card.
The domain name system (DNS) is an internet service that is required because the Internet does not recognize the text-based web address or e-mail address that you type into your Web browser or e-mail application. All or part of a web address or an e-mail address is a domain name, and DNS translates this domain name into an IP address that is recognized by the Internet. Dynamic DNS server – If you are using dynamic IP addressing, Inmarsat recommends that you use a dynamic DNS server. A dynamic DNS server updates the IP address information in the DNS database each time your IP address changes. A dynamic DNS server also enables a computer using a dynamic IP address to use network applications that normally require a static IP address, for example FTP servers. This service requires subscription with a Dynamic DNS provider. Static DNS Server – If you are using static IP addressing, Inmarsat recommends that you use a static DNS server. If you select this option, you must enter the IP address of the primary DNS server. This is supplied by your internet service provider. Optionally, you can enter the IP address of a secondary DNS server, also supplied by your ISP. This is used in the event of failure of the primary DNS server.
Error correction ensures that very little data is lost during transfer by asking for dropped packets to be re-sent. However, because it holds subsequent data whilst the packet is being re-sent, you may notice some jitter or delay in the received data. This is normal for most data types. For real-time applications, such as Voice over IP (VoIP) or video, you may find that the level of jitter or delay is too great. In this case, it is recommended that you remove error correction. Removing error correction minimizes delay and jitter, but note that a small amount of data may be lost during transfer, because dropped data packets are not resent.
A header is the component of a data packet that precedes the data that you are sending. The header contains information such as source and destination address, error checking and other administrative details. In most data types this does not noticeably affect the data transmission rates. However, in multimedia applications such as voice and video, the header can significantly affect performance. Inmarsat recommends that you switch on header compression for multimedia applications, such as video.