Practical_4.1 by Farhath Fairooz
Practical 01
01)
Repeater:
A repeater is a basic networking device that operates at the physical layer of the
OSI model.
Its primary function is to regenerate and retransmit signals on a network,
effectively extending the range of a network by amplifying and boosting weak
signals.
Repeaters are typically used in situations where network cables or signals need to
travel long distances without significant degradation.
They are relatively simple devices and don't have any intelligence or the ability to
filter traffic.
Hub:
A hub is also a basic networking device that operates at the physical layer.
Hubs are essentially multi-port repeaters; they take incoming data from one port
and broadcast it to all other ports on the device.
They are very inefficient and can cause network congestion because all connected
devices receive all data, regardless of whether it is intended for them.
Hubs are rarely used in modern networks as they have been largely replaced by
switches.
Switch:
A switch is a more advanced networking device that operates at the data link layer
of the OSI model.
Unlike hubs, switches are intelligent devices that can filter and forward data only
to the specific device it is intended for, based on MAC addresses.
This leads to more efficient and less congested networks compared to hubs.
Switches are fundamental components of most modern Ethernet networks.
Bridge:
A bridge is a device that operates at the data link layer and is used to connect and
filter traffic between two or more network segments.
It makes decisions on whether to forward or filter traffic based on the MAC
address.
Bridges are used to create smaller collision domains, which can improve network
performance by reducing collisions.
In modern networks, the role of bridges is often integrated into switches.
Router:
A router is a networking device that operates at the network layer of the OSI
model.
Routers connect different networks, such as local area networks (LANs) and the
wider internet and make decisions on how to route data between them.
They use routing tables and logical addressing (e.g., IP addresses) to determine
the best path for data to reach its destination.
Routers provide network segmentation, security, and can perform Network
Address Translation (NAT) for connecting multiple devices to the internet through
a single IP address.
Gateway:
A gateway is a device that acts as an interface between two different networks,
often using different protocols or communication standards.
It translates data between the two networks to enable communication, making it
possible for data to flow between them.
Gateways can be hardware or software-based and are commonly used in
scenarios like connecting a local network to the internet, where translation
between LAN protocols and internet protocols is necessary.
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2.
WAN Routers: You will need WAN routers at both branches. These routers are
specifically designed for WAN connections and can establish a secure and efficient
connection between the two locations.
Leased Line or Internet Connection: To establish the WAN connection, you'll need
an appropriate connection method, such as a leased line (e.g., MPLS) or an
internet connection (e.g., VPN). The choice depends on your budget, bandwidth
requirements, and security considerations.
Firewalls: To enhance security, it's a good practice to have firewalls at both
branches to protect your network from external threats.
WAN Cabling or Connection: Depending on the type of WAN connection chosen
(leased line, VPN, etc.), you might need specific cabling or a VPN setup.
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Implement robust firewall and intrusion detection systems.
Segment the network for added security.
Use VPNs for secure remote access.
Regularly update software and hardware.
Enforce security policies and provide staff training.
Prevent DDoS attacks and encrypt sensitive data.
Employ access control, authentication, and strong logging.
Conduct security audits and penetration testing.
Maintain an incident response plan.
Evaluate the security of third-party vendors.
Backup data and have a disaster recovery plan.
Comply with legal and regulatory requirements.
Practical 02
a) Coaxial Cable:
Coaxial cable consists of a central conductor, an insulating layer, a metallic shield,
and an outer insulating layer.
It is commonly used for cable television (CATV), broadband internet, and some
networking applications.
Coaxial cables offer good bandwidth and are relatively resistant to signal
interference.
They are more robust and can transmit signals over longer distances compared to
twisted pair cables.
b) Fiber-Optic Cable:
Fiber-optic cables use light signals to transmit data. They consist of a core made of
glass or plastic fibers, surrounded by cladding and an outer protective layer.
Fiber optics offer extremely high bandwidth and are known for their ability to
transmit data over very long distances without signal degradation.
They are immune to electromagnetic interference (EMI) and are often used in
high-speed internet, telecommunications, and long-distance networking.
c) Twisted Pair Cable:
Twisted pair cables come in two main categories: unshielded twisted pair (UTP)
and shielded twisted pair (STP).
UTP is commonly used in Ethernet networking, telephone lines, and is the most
prevalent cabling for LANs.
Twisted pair cables consist of pairs of insulated copper wires twisted together to
reduce electromagnetic interference.
They offer moderate bandwidth and are cost-effective but are more susceptible to
EMI compared to coaxial or Fiber-optic cables.
1.
Bandwidth:
Coaxial Cable: Provides moderate to high bandwidth, suitable for cable television
and broadband internet.
Fiber-Optic Cable: Offers extremely high bandwidth, making it ideal for high-speed
data transmission.
Twisted Pair Cable: Provides lower to moderate bandwidth, commonly used in
Ethernet networks.
Signal Interference:
Coaxial Cable: Relatively resistant to signal interference due to its shielding.
Fiber-Optic Cable: Immune to electromagnetic interference (EMI) because it uses
light signals.
Twisted Pair Cable: Susceptible to EMI, especially in UTP configurations, but less
so in STP configurations.
Distance:
Coaxial Cable: Can transmit signals over moderate distances, often used for cable
TV.
Fiber-Optic Cable: Suitable for long-distance transmissions, can span several
kilometers without signal degradation.
Twisted Pair Cable: Limited to shorter distances, typically within local area
networks (LANs).
Speed:
Coaxial Cable: Supports high data transfer rates, but not as fast as fiber optics.
Fiber-Optic Cable: Capable of extremely high data transfer speeds, making it ideal
for high-speed internet and long-distance networks.
Twisted Pair Cable: Offers lower data transfer rates compared to coaxial and fiberoptic cables.
Cost:
Coaxial Cable: Moderately priced, making it cost-effective for cable TV and
broadband.
Fiber-Optic Cable: Generally more expensive due to the cost of optical
components and installation.
Twisted Pair Cable: Cost-effective, particularly UTP, making it popular for LANs.
Size and Weight:
Coaxial Cable: Bulkier and heavier compared to twisted pair and fiber-optic cables.
Fiber-Optic Cable: Thin and lightweight, making it easier to install and handle.
Twisted Pair Cable: Lightweight and flexible, easier to manage compared to coaxial
cable.
Security:
Coaxial Cable: Offers reasonable security due to its shielding, but not as secure as
fiber optics.
Fiber-Optic Cable: Highly secure because tapping into the cable without detection
is extremely difficult.
Twisted Pair Cable: Offers limited security, especially in UTP configurations, as it is
susceptible to eavesdropping.
2.
High Bandwidth and Long-Distance Data Transmission:
Best Choice: Fiber-Optic Cable
Why: Fiber-optic cables provide extremely high bandwidth and can transmit data
over long distances without signal degradation, making them ideal for applications
like high-speed internet, long-distance telecommunications, and data centers.
Moderate Bandwidth and Moderate-Distance Data Transmission:
Best Choice: Coaxial Cable
Why: Coaxial cables offer good bandwidth and are relatively resistant to
interference. They are well-suited for applications like cable television, broadband
internet, and some networking needs.
Local Area Networking (LAN):
Best Choice: Twisted Pair Cable (UTP or STP, depending on interference concerns)
Why: Twisted pair cables are commonly used in LANs due to their costeffectiveness and flexibility. UTP is suitable for typical office environments, while
STP can be used where there is a need for additional protection against
interference.
Security-Sensitive Applications:
Best Choice: Fiber-Optic Cable
Why: Fiber-optic cables are the most secure transmission medium as they are
extremely difficult to tap into without detection. They are ideal for applications
where data security is critical.
Cost-Effective Data Transmission in Short Distances:
Best Choice: Twisted Pair Cable (UTP)
Why: UTP is cost-effective and suitable for shorter-distance applications, such as
within a building or office. It is commonly used for Ethernet networks and
telephone lines.
Resistance to Electromagnetic Interference (EMI):
Best Choice: Fiber-Optic Cable (immune to EMI)
Alternative: Shielded Twisted Pair Cable (STP)
Why: Fiber-optic cables are immune to EMI. If STP is needed, it offers better EMI
protection compared to UTP or coaxial cable.