Trace route finds out when the packet has reached the
destination point by including a port number that is outside
of the normal range. When it is received, a "port
unreachable" message is returned, enabling trace route to
determine the time length of the final hop.
TCP is Transmission Control Protocol and connection oriented
UDP is User Datagram Protocol and connectionless protocol.
use in stock market for information sending and receiving.
5- Layer architecture of the Internet:
Application (Layer 5)
Transport (Layer 4)
Network (Layer 3)
Data Link (Layer 2)
Physical (Layer 1)
Differences between wireless network and wired network:
(1) Wired network uses wires (e.g., twisted pair, coax,
fiber optic) as transmission
media in physical layer. Wireless network uses air waves,
which requires different coding,
(2) Interference and collision is much more severe in
wireless networks. Data link
layer in wireless network uses different techniques to avoid
collision and make sure data
(3) Wireless network needs to deal with device location and
handover in network
layer. In wireless ad hoc networks, routing can be different
than wired networks.
(4) No big difference between wireless and wired network in
(5) Application layer is unaware of the physical aspects of
the network. Application
layer in wired network supports services like FTP, SMTP etc.
One can also take the
physical layer characteristics into account when writing an
different type of signalling in used betweeb two
exchanges. its depend upon type of exchange some exchange
used q sig between each other some excahnges used isdn
between exchanges. so many other type. there are five tyope
of signaling is being used in the world
Buffering is a method of overlapping the computation of a
job with its execution. It temporarily stores input or
output data in an attempt to better match the speeds of two
devices such as a fast CPU and a slow disk drive. If, for
example, the CPU writes information to the buffer, it can
continue in its computation while the disk drive stores the
It is sampled at 8Khz as per Sampling theorem to reproduce
successfully in the other end.
Only Two Hops
The time taken for 1 satellite hop in voice
communication is 1/2 seconds
Bluetooth Works on 2.4 GHz
VSWR STANDS FOR VOLTAGE STANDING WAVE RATIO
THE RATIO OF THE MAXIMUM TO MINIMUM VALUE OF STANDING WAVE
PATTERN ALONG A TRANSMISSION LINE TO WHICH A LOAD IS CONNECTED.
IT SHOW HOW MUCH SIGNAL IS TRANSMITTED AND REFLECTED BACK.
USING SITE MASTER WE CAN MEASURE VSWR.
ITS RANG IS 1.00-1.30