Monday, October 12, 2009

Route

Introduction to Routing

Routing is an extremely important function of IP. It is the process of choosing a path over which to send packets. The device that performs this task is called a router, which forwards packets from one physical network to another. Your knowledge of IP will enable you to see the correlation between IP and routing.
The Internet layer, or OSI/RM network layer (Layer 3), performs the routing function. A packet, or datagram, carries sufficient information for routing from the originating host to the destination host using the IP address. Packets may traverse several networks before reaching their destination host.
Packets are routed transparently, and not necessarily reliably, to the destination host. The term "transparent," when applied to routing, means that after the routing hardware and software are installed, changes are undetectable by users because the routing process is largely automated. The complexity of routing is not visible to the user. The transport or application layer is responsible for reliability, which ensures that the data arrives at the other end.


Routing can be summarized as:

  • The process that determines the path that packets will travel across networks.
  • One of the most important IP functions.
Routing can be divided into two general classifications: direct and indirect.

Bluetooth

Named after a tenth-century Danish king, Bluetooth is a specification for a small form-factor, low-cost radio solution providing links between mobile computers, mobile phones and other portable handheld devices, and connectivity to the internet which it is hoped will revolutionise mobile computing and communications by providing freedom from wired connections. The initiative is backed by leaders in the telecommunications, computing, and network industries - including 3Com, Ericsson, IBM, Intel, Lucent, Motorola, Nokia and Toshiba - and more than 1300 adopter companies. Microsoft's decision to join the group driving the standard at the end of 1999 significantly increased hopes that one of the problems that had afflicted Bluetooth hitherto - namely that the standard had yet to extend beyond hardware compatibility to encompass the software that runs across it - would not be allowed to undermine the standard to the extent that it had its forerunner, infrared.

Bluetooth's chief advantage over infrared is that Bluetooth does not require line of sight. Its backers hope the component costs will be so low that it will ultimately replace infrared. Others believe that, although there are clear areas of overlap, IrDA and Bluetooth are complementary with either being the most appropriate for certain applications and intended usage models.

Bluetooth operates in the unlicensed Industrial Scientific and Medical (ISM) 2.4GHz band, ranging from 2.4 to 2.4835 GHz in the US, Japan and Europe. Parts of this band are also available in France and Spain. By using the 2.4 GHz band, Bluetooth Wireless Technology promises to be a universal wireless solution. Essentially, it is the same kind of microwave radio technology that has given us wireless door chimes and automatic garage door openers. It draws heavily on existing wireless LAN technology since it is based around the IEEE's 802.11 - the existing standard for wireless Ethernet. The main differences are that in order to consume less power, Bluetooth is initially restricted to an operating distance of just 10 metres and a speed of approximately 1 Mbit/s.

Tag

Assignment Lanka Tag Cloud
Computer Networks The History of Local Area Networks, LAN, The Topologies of a Networks, LANs describe different types of transmission Medias, Local Area Networks Access Methods, Carrier Sense Multiple Access with Collision Detect, Development of LAN Technologies. LAN -Token Ring, LAN Ethernet Digital, LAN - Ethernet Sun microsystems, LAN - Ethernet Mixed Environment, LAN - Token Ring was introduced by IBM LAN - IBM implementation of Token Ring, Token Ring Novell, LAN Token Ring - in a mixed environment, LAN - Fiber Distributed Data Interface, LAN - ATM, LAN Components, LAN Switching Methods, Virtual Local Area Network, Port based VLAN, Mac based VLAN, Protocol based VLAN, User Base VLAN, PC networks Components, PC networks Shared resources, PC Network operating systems, PC networks Novell Netware, PC networks Windows NT, PC networks IBM LAN Server Computer Programming Languages HTML Language, The Generations of Programming Languages, Different types of High Level Languages, Different types of High Level Languages Disadvantages
Computer Networks - IBM LAN Server, Windows NT Networks, Novell Netware, Network operating systems, Networks Shared, Networks Components, User Base, Protocol based, Mac based, Port based, VLAN, LAN Switching, LAN Components, ATM, Fiber Data, Token Ring, Token Ring Novell, IBM implementation, Ethernet, Sun microsystems, Ethernet Digital, Token passing, LAN Technologies, CSMA/CD, Access Methods, Transmission, Networks, The History of Local Area Networks, LAN