Information Technology Reference
In-Depth Information
frames. This layer provides the delivery of data between systems using a
media or hardware address, such as the Ethernet or Media Access
Control (MAC) address.
Network or Internet Layer:
The third layer is responsible for determin-
ing a path across the Internet between systems that want to communicate.
It understands the data communication and switching technologies used
to interconnect systems. This layer manages the network addressing and
routing of data and locates the remote host based on its assigned IP
address and determines the path through the network (that is, the route)
used to deliver data. Data at this layer is typically referred to as
datagrams
.
➤
Transport Layer:
The fourth layer provides end-to-end error recovery
and flow control. These services ensure that the data is delivered with-
out errors and in sequence without duplication. It controls the exchange
and flow of data. Data at this layer is typically referred to as
packets
.
➤
Application:
The fifth layer provides utilities used by humans including
functionality such as remote logins, file transfers, and so on. Data at this
layer is typically referred to as
messages
or
streams
.
➤
Figure 10.1 provides a side-by-side comparison of the OSI and TCP/IP net-
working models.
7
Application
6
Presentation
5
Application
5
Session
4
Tr ansport
4
Tr ansport
3
Network
3
Network
2
Data Link
2
Data Link
1
Physical
1
Physical
ISO/OSI Network Model
TCP/IP Network Model
Figure 10.1
Comparing the OSI and TCP/IP networking models.
TCP/IP Networking
The Solaris operating system implements the TCP/IP networking model.
Although Solaris can use several types of networking hardware architectures
such as Ethernet, Token Ring, and FDDI to communicate with other sys-
tems, Ethernet is the de facto networking architecture.
