CCNA

Extended ACL range

100-199

What function is performed by a WLC in a Split MAC Deployment?

Security/QoS management, client authentication, client association

What function is performed by a LAP in a Split MAC Deployment?

“Real-time” operation such as transmitting/receiving, encryption/decryption, and sending beacons/probes

GLBP MAC

**0007**.B400.0102

HSRP

0000\.**0C07**.AC0B

VRRP

0000\.**5E00**.0101

What is the normal OSPF neighbor state for a router that is neither the DR or BDR?

2-Way

Default VTP mode on new switches

Server Mode

When is **PSK** used?

WPA2 passphrase in ASCII format

On which interfaces is the OSPF point-to-point network type enabled by default?

PPP and HDLC

What is Weighted Random Early Detection (WRED)?

Congestion avoidance method that drops lower-priority packers if network congestion is detected

What can cause late collisions on an Ethernet LAN?

Duplex mismatch and long cable segments

Standard ACL range

1-99

External EIGRP AD

170

Internal EIGRP AD

90

Static Route AD

1

Directly Connected AD

0

IS-IS AD

115

OSPF AD

110

RIP AD

120

Router-ID OSPF Selection Order

1. Manuel router ID
2. Highest loopback
3. Highest active IP address

Configure a hostname associated with an IP address

ip host __name__ __ip address__ __subnet mask__

OSPF State Order

1. Down
2. Init
3. Two-way
4. Ex-start
5. Exchange
6. Loading
7. Full

Where is a standard ACL placed?

Placed close to the destination

Where is an extended ACL placed?

Placed close to the source

What command shows the current NAT translations?

show ip nat translations

What command shows the active NAT translations?

show ip nat statistics

Types of Enterprised-managed remote access VPNs

1. Clientless SSL VPN
2. Client-based IPsec VPN

The action of adding a value to a packet header so the packer matches a defined policy

Traffic marking

What is Low Latency Queuing (LLQ)

LLQ is a QoS mechanism that allows delay-sensitive data to be sent first before other packets

What is “config-register 0x2102” used for?

To ensure that the device loads the start up config file during start up

How are syslog levels ordered by?

Syslog levels are ordered by severity whereby 0 is the most severe and 7 is the least

What does ASIC do?

Allows multi-layer switches to forward IP packets without calling on the CPI to make routing decisions

What programming language does YAML look like

Python

What is Cisco Express Forwarding (CEF)?

A packet-switching technique is used within Cisco routers to optimize the forwarding of packets and increase packet-switching speed.

What is the CEF made up of?

1. FIB (Forwarding Information Base)
2. Adjacency Table

What is the FIB?

The FIB is a mirror copy of the routing table

What is the Adjacency Table?

The adjacency table maintains Layer 2 next-hop addresses for all FIB entries

All devices in a service set share the same ___

SSID (Service Set Identifier)

Independent Basic Service Set (IBSS)?

A wireless network in which two or more wireless devices connect directly without using an AP. An example of this is AirDrop so it is not scalable

Basic Service Set (BSS)?

A wireless network in which clients connect to each other via an AP but not directly to each other.

What is a BSSID used for?

Identifies an AP in the BSS

Extended Service Set (ESS)?

One or more interconnected basic service sets (BSSs) and their associated LANs

Mesh Basic Service Set (MBSS)?

One access point is connected to the wired network while the rest of the APS are interconnected wirelessly

How many bits are in an IPv4 address?

32 bits

How many bytes are in an IPv4 address?

4 bytes

How many bits are in an IPv6 address?

128 bits

How many bytes are in an IPv6 address?

16 bytes

What is the default reference bandwidth in OSPF?

100,000,000 bps

OSPF Cost Formula

Interface Cost= Reference bandwidth/interface bandwidth

What are MD5 and SHA used for?

Data integrity

What is AES used for?

Confidentiality

What makes up the three-layer hierarchal model?

1. Core
2. Distribution
3. Access

What makes up the two-layer hierarchal model?

1. Collapsed Core/Distribution
2. Access

What is the purpose of the core layer?

1. provide high-speed **backbone** connectivity
2. functions as **aggregators** for all campus blocks

What is the purpose of the distribution layer?

1. established **Layer 3 routing** boundaries
2. implements **network access policy**

What is the purpose of the access layer?

1. represents the **network edge**
2. provides **network access** to the user

Explain the spine-leaf achitecture.

A network topology that consists of 2 switching layers—a spine and a leaf.

* The leaf layer consists of access switches that aggregate traffic from servers and connect directly to the spine or network core
* Spine switches interconnect all leaf switches in a full-mesh topology.

What command specifies the source for the Cisco IOS Software image to load?

boot system ____

When does refraction occur?

When a wave is bent while entering a medium where the signal travels at a different speed

When does diffraction occur?

Diffraction happens when the wave goes around an object

What causes scattering?

Scattering is caused by dust, smog, uneven surfaces, etc

What is stored in the NVRAM?

NVRAM stores the configuration information on the network server in text form as configuration commands

What is Cisco DNA Center?

Cisco DNA Center is an appliance to configure that provides a GUI and programming interface to design and troubleshoot a network.

What is Cisco DNA Assurance used for?

Used for troubleshooting

What is Cisco DNA Security used for?

Enforce policies and contain threats across the network

What are the 5 main areas of Cisco DNA Center?

1. Design
2. Policy
3. Provision
4. Assurance
5. Platform

What is Cisco DNA Design used for?

Modeling an entire network

What is Cisco DNA Policy used for?

Creating policies to automate and simplify network management

What is Cisco DNA Provision used for?

Providing **new services** to users

What is Cisco DNA Assurance used for?

Proactive **monitoring** and **insights** from the network to **predict** problems and **ensure** policies and configurations achieve the business' intent

What is Cisco DNA Platform used for?

Provides the use of **API**s for end-to-end solutions and add support for multi-vendor devices

Four WLC Deployments

1. Unified WLC
2. Cloud-based WLC
3. Embedded WLC
4. Mobility Express WLC

Unified WLC

The WLC is a hardware appliance in a **central** **location** of the network

Cloud-based WLC

The WLC is a **virtual** **machine** running **on** a **server**, usually in a private cloud in a data center.

Embedded WLC

The WLC is **integrated** within a **switch**

Mobility express WLC

The WLC is **integrated** within an **Access** **Point**

What is the function of a WLC?

WLC manages network access points that allow wireless devices to connect to the network.

What is Light Weight Access Point Protocol (LWAPP)?

An open Cisco proprietary wireless management protocol

What is Control and Provisioning of Wireless Access Points (CAPWAP)?

An open industry-standard protocol for wireless management

Describe Split MAC

Some traffic is performed by the AP and the remainder is handled by the WLC

What is (Link Aggregation) LAG?

Also known as EtherChannel to bundle multiple ports into one.

What is FlexConnect mode?

Allows the AP to locally switch traffic between wired and wireless networks if CAPWAP tunnels to the WLC go down.

What is Local mode?

The default mode for an LAP where the AP offers a BSS for clients to associate with

What is Sniffer mode?

The AP does not offer a BSS for clients, but it is dedicated to capture 802.11 frames and sending them to a device running software such as Wireshark

What is Moniter mode?

The AP does not off a BSS for clients, but it is dedicated to capture 802.11 frames to detect rogue devices.

What is Rogue Detector mode?

The AP does not even use its radio, but listens to traffic on the wired network only to receive a list of suspected rogue clients.

Explain SDN?

A network architecture that separates the control plane from the data plane, allowing network behavior to be defined and controlled using software

What is the control plane?

The "brain" of the network, making decisions about how the network should behave (traffic routing and network topology).

What is the data plane?

The "body" of the network, performing the actual work of forwarding network traffic that has been defined

What is the application layer (SDN)?

The interface for network administrators to configure and manage the network. It includes the network management software and the APIs used to interact with the network.

List the SDN layers

1. Application Layer
2. Control Layer
3. Data Plane Layer

Define underlay

The physical network of devices and connections which provide IP connectivity (multi-layer switches and their connections)

Define overlay

The virtual network built on top of the physical overlay network

Define fabric

The combination of the **overlay** and the **underlay** (physical and virtual network as a whole)

Explain TCP

Connection-oriented protocol that provides retransmission of lost data packets

Explain UDP

Connectionless protocol that is much fast that TCP

IPV6 Multicast Address

FF00::/8

What is an Anycast Address?

“one to one of many”

What is Modified EUI 64 (EUI-64)

Method of converting a MAC address into a 64-bit interface identifier