Download Review Questions of Switching Networks

1. Describe, with a suitable graph, how the Cisco hierarchical design model is
organized? What is the name of each layer of this model? What functions
provided by each layer?
Answer:
Refers to figure about, the Cisco hierarchical design model is divided into
three discrete layers which called core layer, distribution layer and access
layer. The main functions provided by each layer are:
Access Layer
The access layer interfaces with end devices, such as PCs, printers, and IP
phones, to provide access to the rest of the network. The access layer can
include routers, switches, bridges, hubs, and wireless access points (AP). The
main purpose of the access layer is to provide a means of connecting devices
to the network and controlling which devices are allowed to communicate on
the network.
Distribution Layer
The distribution layer aggregates the data received from the access layer
switches before it is transmitted to the core layer for routing to its final
destination. The distribution layer controls the flow of network traffic using
policies and delineates broadcast domains by performing routing functions
between virtual LANs (VLANs) defined at the access layer. VLANs allow you
to segment the traffic on a switch into separate subnetworks. Distribution
layer switches are typically high-performance devices that have high
availability and redundancy to ensure reliability.
Core Layer
The core layer of the hierarchical design is the high-speed backbone of the
internetwork. The core layer is critical for interconnectivity between
distribution layer devices, so it is important for the core to be highly available
and redundant. The core area can also connect to Internet resources. The
core aggregates the traffic from all the distribution layer devices, so it must
be capable of forwarding large amounts of data quickly.
2. What are the benefits of a Hierarchical Network?
Ans:
3. What is a Converged Network?
Ans:
Convergence is the process of combining voice and video communications on a data
network.
4. Describe, using your own word, what is VLAN?
Ans:
A VLAN is a logically separate IP subnetwork. VLANs allow multiple IP networks
and subnets to exist on the same switched network. A VLAN allows a network
administrator to create groups of logically networked devices that act as if they
are on their own independent network, even if they share a common infrastructure
with other VLANs. When you configure a VLAN, you can name it to describe the
primary role of the users for that VLAN.
5. What are the Benefits of a VLAN?
Ans:
The primary benefits of using VLANs are as follows:
Security - Groups that have sensitive data are separated from the rest of the
network, decreasing the chances of confidential information breaches
Cost reduction - Cost savings result from less need for expensive network upgrades
and more efficient use of existing bandwidth and uplinks.
Higher performance - Dividing flat Layer 2 networks into multiple logical
workgroups (broadcast domains) reduces unnecessary traffic on the network and
boosts performance.
Broadcast storm mitigation - Dividing a network into VLANs reduces the number of
devices that may participate in a broadcast storm.
Improved IT staff efficiency - VLANs make it easier to manage the network
because users with similar network requirements share the same VLAN. When you
provision a new switch, all the policies and procedures already configured for the
particular VLAN are implemented when the ports are assigned. It is also easy for
the IT staff to identify the function of a VLAN by giving it an appropriate name
Simpler project or application management - VLANs aggregate users and network
devices to support business or geographic requirements. Having separate functions
makes managing a project or working with a specialized application easier, for
example, an e-learning development platform for faculty. It is also easier to
determine the scope of the effects of upgrading network services.
6.The devices belong to two different VLAN connect to the same switch,
configuring communication between devices on different VLANs requires the use
of which layer of the OSI model? Explain why?
Answer:
The layer three of OSI model is required to configure the communication
between two VLANs even they are connected to the same switch. The reason is
that different VLAN should be configured to different subnet. Exchange
information between different subnets need layer three device- Router.