How CIDR Works

How CIDR Works

      CIDR was a dramatic break from tradition in that it completely abandoned the rigid classes of addresses.
The original IPv4 address architecture used an 8-bit network number for Class A addresses, a 16-bit
network number for Class B addresses, and a 24-bit number for Class C addresses. CIDR replaced these
categories with a more generalized network prefix. This prefix could be of any length rather than just 8,
16, or 24 bits. This allows CIDR to craft network address spaces according to the size of a network
instead of force-fitting networks into presized network address spaces.
Each CIDR-compliant network address is advertised with a specific bit mask. This mask identifies the
length of the network prefix. For example, 192.125.61.8/20identifies a CIDR address with a 20-bit
network address. The IP address can be any mathematically valid address regardless of whether that
address was originally part of the Class A, B, or C range! CIDR-compliant routers look at the number
after the /to determine the network number. Therefore, the former Class C address 192.125.61.8
previously had a network number of 192.125.61and a host number of 8. As a Class C address, you
could provide addresses for a maximum of 254 hosts within the network. Using CIDR, the architectural
limitations of the 8-bit boundaries between address components is eliminated. To better understand how
this works, it is necessary to translate the decimal number to binary.

What is dsl

What is dsl

                 Dsl it means Digital subscriber line it is a technologies that provide internet access by transmitting digital data over the local telephone network.Dsl understood means the adsl.Dsl service is delivered with wired telephone service on the same telephone line.Telephone are the connected by the telphone exchange via the local loop.Many Dsl technologies implement on atm layer over the low leverl layer.

Wireless network

Wireless network

     Over the past five years, the world has become increasingly mobile. As a result, traditional ways of
networking the world have proven inadequate to meet the challenges posed by our new collective
lifestyle. If users must be connected to a network by physical cables, their movement is dramatically
reduced. Wireless connectivity, however, poses no such restriction and allows a great deal more free
movement on the part of the network user. As a result, wireless technologies are encroaching on the
traditional realm of "fixed" or "wired" networks. This change is obvious to anybody who drives on a
regular basis. One of the "life and death" challenges to those of us who drive on a regular basis is the
daily gauntlet of erratically driven cars containing mobile phone users in the driver's seat.
We are on the cusp of an equally profound change in computer networking. Wireless telephony has
been successful because it enables people to connect with each other regardless of location. New
technologies targeted at computer networks promise to do the same for Internet connectivity. The most
successful wireless networking technology this far has been 802.11.