Anna University Coimbatore 2009 B.E Electronics

into a single data unit. The combining process is called concatenation.
8. elaborate the kinds of multiplexing?
The kinds of multiplexing are,
Upward multiplexing
Downward multiplexing
9. elaborate the 2 possible transport services?
Two basic kinds of transport services are,
Connection service
Connectionless services
10. The transport layer creates the connection ranging from source and destination.
elaborate the 3 events involved in the connection?
For security, the transport layer may create a connection ranging from the two
end ports. A connection is a single logical path ranging from the source and destination
that is associated with all packets in a message. Creating a connection involves
three steps:
· Connection establishment
· Data transfer & Connection release.
11. What is meant by congestion?
Congestion in a network occurs if user sends data into the network at a rate
greater than that allowed by network resources.
12. Why the congestion occurs in network?
Congestion occurs because the switches in a network have a limited buffer
size to store arrived packets.
13. What is meant by quality of service?
The quality of service describes a set of attributes related to the performance of
the connection. For every connection, the user can request a particular attribute every
service class is associated with a set of attributes.
14. elaborate the 2 categories of QoS attributes?
The 2 main categories are
User Oriented
Network Oriented
15. List out the user related attributes?
User related attributes are
SCR – Sustainable Cell Rate
PCR – Peak Cell Rate
MCR- Minimum Cell Rate
CVDT – Cell Variation Delay Tolerance
16. elaborate the networks related attributes?
The network related attributes are,
Cell loss ratio (CLR)
Cell transfer delay (CTD)
Cell delay variation (CDV)
Cell fault ratio (CER)
17. What is the difference ranging from service point address, logical address and
physical address?
Service point addressing Logical addressing Physical addressing
The transport layer header
includes a kind of address
called a service point
address or port address,
which makes a data delivery
If a packet passes the
network boundary we need
a different addressing to
differentiate the source and
destination systems. The
If the frames are to be
distributed to various
systems on the network, the

Earning:   Approval pending.