Wide Area Network

What is the primary function of a backbone network in a corporate infrastructure?

It connects local area networks (LANs) and wide area networks (WANs) together.

Which specific layer of a backbone network is responsible for connecting access LANs within a building?

The distribution layer (also known as the Building BN).

What is the primary role of the core layer in a campus backbone network?

It connects the backbone networks of different buildings across a campus.

At which OSI layer does a network hub operate?

Layer 1 (Physical layer).

How does a hub distribute incoming messages to other devices on the network?

It broadcasts the message to every device connected to it.

Why is a network hub unable to send and receive data simultaneously?

It operates in half-duplex mode on a shared physical medium.

Which address type does a Layer 2 switch use to determine where to forward a message?

The Media Access Control (MAC) address.

What is the primary difference between how a switch and a hub handle message delivery?

A switch forwards messages to a specific destination MAC address, while a hub broadcasts to all devices.

At which OSI layer does a standard network router operate?

Layer 3 (Network layer).

Which address type is used by a router to determine the best path for data transmission?

The Internet Protocol (IP) address.

What information does a router add to a data frame before sending it to the next hop?

The MAC address for the next hop on the route.

What is the specialized role of a Layer 3 switch in a Virtual LAN (VLAN) environment?

It functions as both a high-speed switch and a router to manage inter-VLAN traffic.

What are the two most common types of physical cabling used in backbone networks?

Twisted-pair (Cat5/Cat5e) and fiber optic cable.

Why are Layer 2 switches considered 'transparent' devices in a network?

They forward messages without making any changes to the original content.

What are the three major categories of backbone network architectures?

Switched backbones, routed backbones, and Virtual LANs (VLANs).

In which layer of a backbone network is a switched architecture most commonly used?

The distribution layer (Building BN).

Where are all the switches in a switched backbone network typically centralized?

In a single wiring closet, such as an IDF or MDF.

What is the logical topology of a switched backbone network?

A logical star topology.

What is the physical topology of a switched backbone network?

A physical star topology.

Which component in a network closet terminates building cables and provides ports for patch cables?

The patch panel.

What are two common names for a routed backbone network architecture?

Subnetted backbones or hierarchical backbones.

In which layer of a campus network is a routed backbone typically implemented?

The core layer (Campus BN).

What is considered the primary advantage of using a routed backbone architecture?

Effective LAN segmentation between different subnets.

What is a significant performance drawback of routed backbones compared to switched backbones?

They tend to be slower because routers require more time to process Layer 3 headers.

Why are routed backbones generally more difficult to manage than switched backbones?

They involve complex subnetting and the maintenance of detailed routing tables.

How does a Virtual LAN (VLAN) segment a network differently than traditional architectures?

It groups devices logically via software rather than based on their physical hardware location.

Which hardware component is essential for enabling and managing Virtual LANs (VLANs)?

High-speed Layer 3 switches.

What identifier is used at the software level to distinguish between different Virtual LANs?

A VLAN ID.

What is the significance of VLANs being 'transparent' to the client devices?

The connected devices and outside networks are unaware that logical segmentation is occurring.

How do VLANs facilitate traffic prioritization for different types of data?

They use Quality of Service (QoS) tags within the Ethernet frames.

What is a primary disadvantage of implementing VLANs in a network architecture?

Increased complexity and management overhead.

Which backbone architecture offers the best cost-to-performance ratio for the distribution layer?

The switched backbone network.

What is the recommended technology standard for a backbone's distribution layer?

Gigabit Ethernet.

What is the recommended technology standard for a backbone's core layer?

Gigabit Ethernet or faster.

What design strategy is recommended to ensure high availability in a backbone network?

The use of redundant devices and connections throughout the architecture.

Backbone networks connect LAN and _____ together.

WAN

The core layer of a backbone network connects different buildings and is often called a _____ BN.

Campus

What action does a router take after determining the best route but before forwarding a packet?

It reassembles the message and adds the MAC address for the next hop.

What are the three common physical form factors for network switches?

Desktop, rack-mounted, and chassis.

Why is LAN segmentation through routed backbones considered beneficial for performance?

It reduces broadcast traffic by limiting it to individual subnets.

Concept: VLAN

Definition: A software-based network segmentation method that groups devices logically regardless of their physical location.

What type of backbone architecture is most suitable for an organization needing high flexibility over cost?

A Virtual LAN (VLAN) architecture.

The logical star topology of a switched backbone means all devices appear to connect to a central _____.

Switch

Which device reads IP addresses to determine the best route for a data packet?

A router.

What is a major cost-related disadvantage of using Layer 3 switches instead of Layer 2 switches?

Layer 3 switches are significantly more expensive.

Under what circumstance is a VLAN architecture most commonly utilized in practice?

In complex networks spanning multiple geographic locations.

In a network closet, what connects a switch port to a patch panel port?

A patch cable.

What acronym refers to the primary wiring closet that serves as the central hub for a building's backbone?

MDF (Main Distribution Frame).

What is the primary role of the distribution layer backbone in a multi-story building?

Connecting the individual LANs on each floor to the building's main router or switch.

Why is fiber optic cable often preferred over Cat5e for the core layer of a backbone network?

It supports higher bandwidth and longer distances between buildings.

What is the first step a switch performs when it receives an Ethernet frame?

It reads the frame to identify the destination MAC address.

In a routed backbone, what happens to a message at each router along the path?

The router strips the old MAC address and adds a new one for the next segment.

Which backbone architecture is characterized by routers connecting different subnets in a hierarchical fashion?

The routed backbone network.

How does a VLAN improve network security through management software?

It isolates sensitive traffic into specific logical groups that are inaccessible to other users.

What is a common best practice regarding the speed of the core layer compared to the distribution layer?

The core layer should be at least as fast as, or faster than, the distribution layer.