Page 149 - Computer_Science_F5

Computer Science MAC address table may have its own set of devices and
requires its own logical network for
Switches build a MAC address table by
learning the source MAC addresses of security and traffic management purposes.
incoming frames and associating them Using switched LANs with VLANs, the
with the corresponding ports. This network administrators can perform the
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dynamic learning process enables efficient following:
frame forwarding. (i) Create separate VLANs: for example
VLAN 5 for Sales, VLAN 10 for
(f) Components of a switched LAN: Accounting, and VLAN 15 for IT.
Switches: Switches are the central Also they can assign switch ports to
devices in a switched LAN, connecting the appropriate VLANs based on the
end devices (such as computers, printers, devices connected.
and servers) as well as other network (ii) Isolate traffic: for example traffic
devices (like routers and firewalls). from accounting devices stays within
VLAN 10, sales traffic stays within
End devices: End devices refer to
computers, servers, printers, and other VLAN 5, and IT traffic stays within
devices that connect to the network VLAN 15. The purpose of this is
through switches. reduce unnecessary broadcast traffic
and improves security by isolating
Cabling: Cabling involves the use of departments.
Ethernet cables, such as Cat5e or Cat6, (iii) Enable inter-VLAN communication:
to establish connections between devices E n a b l i n g i n t e r -VL AN
and switches. communication through the use of
a Layer 3 switch or router allows
Network Interface Cards (NICs): NICs for the necessary communication
are hardware components present in each between departments while still
device, providing the physical interface preserving the segmentation of
for connecting to the network. VLANs.

Router (for inter-VLAN communication):
Routers are devices that enable Activity 3.3:
communication between multiple VLANs
by routing traffic between them. In some Exploring of the Data Link Layer
cases, routers are integrated into Layer 3 Aim:
switches.
Understand how the data link layer
Real environment of the use of a switched facilitates hop-to-hop delivery
LAN is when the office have several of frames and its role in network
departments such as HR, Sales, Accounts, communication.
Procurement, and IT. Each department

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Computer Science Form 5.indd 140 23/07/2024 12:33