Chapter 17: Build a Small Network
Force using IPv4
-4
Force using IPv6
-6
What does CDP stand for?
Cisco Discovery Protrocol
Reliability is another important part of what?
Network Design
How many pings does a Cisco IOS send?
Sends five ICMP echo messages
What does the Windows command ipconfig /all do?
Used to view IPv4/IPv6 address information, mac, and default gateway.
How do you disable CDP globally on a cisco device?
no cdp run in the global configuration mode
A technician has established a remote connection to router R1 to observe debug output. The technician enters the debug ip icmp command then pings a remote destination. However, no output is displayed. Which command would the technician have to enter to display log messages on a remote connection? monitor debug output monitor terminal terminal monitor terminal monitor debug
terminal monitor
Which privileged EXEC mode command would be used to display log messages on a terminal (virtual console)?
terminal monitor
Trace round-trip path (IPv6-only)
-R
Source address to use (IPv6-only)
-S sraddr
IOS PING Indicators ......
A period means that time expired waiting for an echo reply message This indicates a connectivity problem occurred somewhere along the path
Up to one network layer address for each protocol supported
Address List
What are two forms of software programs or processes that provide access to the network? (Choose Two) antivirus software application layer services gaming software network applications productivity software virtual machine software
Application Layer Services Network Application
Information gathered by the protocol analyzer is evaluated based on what?
Based on the source and destination of the traffic, as well as the type of traffic being sent.
Itemized IT budget, including fiscal year equipment purchasing budget
Budget
The cost of a switch or router is determined by its what?
Capacity and Features NOTE: This includes the number and types of ports available and the backplane speed.
How do you created a network baseline?
Creating an effective network baseline is accomplished over a period of time. Measuring performance at varying times and loads will assist in creating a better picture of overall network performance.
Network devices are available in what two configurations?
Fixed and Modular physical configurations
A good network design will implement what to classify traffic carefully according to priority during times of congestion.
Quality of Service (QoS)
SSH is a secure alternative to what?
Telnet
A newly hired network technician is given the task of ordering new hardware for a small business with a large growth forecast. Which primary factor should the technician be concerned with when choosing the new devices? . redundant devices devices that have support for network monitoring devices with support for modularity devices with a fixed number and type of interfaces
devices with support for modularity
What commands on a MAC OS is used to verify the host IP settings?
networksetup -listallnetworkservices networksetup -getinfo <network service>,
How to you disable CDP on a specific interface?
no cdp enable
A technician is using the debug ip icmp privileged EXEC command to capture live router output. Which commands would stop this debug command on a Cisco router? (Choose two.) debug ip icmp off no debug debug ip icmp no debug ip icmp undebug all undebug debug ip icmp
no debug ip icmp undebug all
What command is useful for troubleshooting DNS on a windows machine?
nslookup
Which network design consideration would be more important to a large corporation than to a small business? firewall internet router low port density switch redundancy
redundancy
What Cisco IOS command is used to provides the following information about each CDP neighbor device
show cdp neighbor
Which Cisco IOS command reveals the IP address of a neighboring device?
show cdp neighbors detail
To verify the interface status and see if there are any error messages
show interfaces
Which two traffic types require delay sensitive delivery? (Choose two.) Video Voice web email FTP
video and voice
In Windows-based machines, when the device cannot contact a DHCP server, Windows will automatically assign an address belonging to what range?
169.254.0.0/16
What does APIPA stand for?
Automatic Private IP Addressing
What does CDP do and why is it important that it runs on the data link layer?
Because CDP operates at the data link layer, Two or more Cisco devices, such as routers that support different network layer protocols, can learn about each other even if layer 3 connectivity has not been established.
Why is documenting snapshots for employees in a small network over a period of time important?
Because it is very useful to identify the evolving protocol requirements and associated traffic flows.
A technician is troubleshooting a network problem. After troubleshooting, the technician concludes that a switch should be replaced. What should the technician do next? Email all users to let them know they are replacing a switch Escalate the trouble ticket to the manager to approve the change Purchase a new switch and replace the defective one Resolve the problem
Escalate the trouble ticket to the manager to approve the change
Priority queuing has four queues what are they?
High Priority - Voice/Video Medium Priority-SMTP Normal Priority-Instant Messaging Low Priority-FTP Note: The high-priority queue is always emptied first
In addition to understanding changing traffic trends, a network admin must be aware of what?
How network use is changing
What is necessary to plan and use when implementing a network? device names IP addressing scheme MAC addressing scheme printer location
IP addressing shceme
What does the windows command ipconfig /renew do?
If a host is configured as a DHCP client, the IP address configuration can be renewed using this command
The network infrastructure must support the real-time applications Existing devices and cabling must be tested and validated Newer networking products may be required
Infrastructure
What factors must be considered when supporting real time application for a small business network?
Infrastructure VoIP IP telephony Real-Time Applications
There are many ways to accomplish redundancy in a network. Redundancy can be accomplished by doing what?
Installing duplicate equipment and duplicate network links for critical areas.
These network protocols comprise the fundamental toolset of a network professional. Each of these network protocols define:
Processes on either end of communication session Types of messages Syntax of the messages Meaning of informational fields How messages are sent and the expected response Interaction with the next lower layer Note: Many companies have established a policy of using secure versions (e.g. , SSH, SFTP, and HTTPS) of these protocols whenever possible.
What is the default gateway?
The default Gateway for an end device is the closest networking device that can forward traffic to other networks.
Which statement correctly relates to a small network? Small networks are complex Small network require an IT department to maintain The majority of businesses are small
The majority of businesses are small
A shift in resource utilization may require what?
The network admin to adjust network resource allocations accordingly
Protocols, applications, and services and their respective traffic requirements should be documented
Traffic Analysis
True of False: A server could provide multiple network services. For instance, a server could be an email, FTP, and SSH server.
True
True or False: One of the first design considerations is the type intermediary devices to use to support the network.
True
True or False: The goal for a good network design, even for a mall network, is to enhance the productivity of the employees and minimize network downtime.
True, the network admin should consider the various types of traffic and their treatment in the network design
IOS PING Indicators U
Uppercase U indicates a router along the path responded with an ICMP Type 3 "destination unreachable" error message Possible reasons include the router does not know the direction to the destination network or it could no find the host on the destination network.
A standard Cisco router will use what IP address as the source of a ping?
Uses the IP address of the interfaces closest to to the destination network source of the ping
Routers and switches in a small network should be configured to support real time traffic such as what?
Voice and videos, in an appropriate manner relative to other data traffic.
We clients and web servers exchange web traffic using Hypertext Transfer Protocol (HTTP) Hypertext Transfer Protocol Secure (HTTPS) is used for secure web communications
Web Server
Network admins must also support common network servers and their required related network protocols, such as:
Web Server - HTTP/HTTPS Email Server - PoP3, IMAP, SMTP FTP Server- FTP, TFTP, SFTP, FTPS DHCP Server- DHCPv4, DHCPv6 DNS Server- DNS
What is required to maintain a high degree of reliability and eliminate single points of failure? accessibility expandability integrity redundancy
redundancy
A network technician suspects that a particular network connection between two Cisco switches is having a duplex mismatch. Which command would the technician use to see the Layer 1 and Layer 2 details of a switch port? show mac-address-table show interfaces show ip interface brief show running-config
show interfaces
What are some IOS commands that can be used to verify correct IP addressing on a switch or router?
show ip interface or show ip interface brief
Toe verify the Layer 3 routing information
show ip route
The Windows tracert command allows the input of several parameters through options in the command line. However, it is not guided like the extended traceroute IOS command. The following output displays the available options for the Windows tracert command.
-d -h maximum_hops -j host-list -w timeout -R -S srcaddr -4 -6
Loose source route along host-list (IPv4-only)
-j host-list
Wait timeout milliseconds for each reply
-w timeout
Cisco OpenDNS address are?
208.67.222.222 208.67.220.220
On a Windows 10 host, the ping command sends how many consecutive ICMP echo request messsages?
4 consecutive ICMP echo replies
Google maintains a public IPv4 and IPv6 DNS server that can bus used by anyone and it is very useful for testing. What are they?
8.8.8.8 2001:4860:4860::8888
Other programs may need the assistance of application layer services to use network resources like file transfer or network print spooling. Though transparent to an employee, theses services are the programs that interface with the network and prepare the data for transfer. Different types of data, whether text, graphics or videos, require different network services to ensure that they are properly prepared for processing by the functions occurring at the lower layers of the OSI model.
Application Layer Services
What is the best practice when using CDP?
Best practices suggest that CDP should be enabled only on interfaces that are connecting to other infrastructure Cisco device. CDP advertisements should be disabled on user-facing ports.
Small office and home office (SOHO) users often rely on DNS servers maintained by who?
By their ISP for name resolution
The expense of ________ runs required to connect every device on the network must also be considered.
Cable
For example, whether a specific device is a Layer 2 switch or layer 3 switch
Capabilities list
Where are Cisco IOS debug output messages sent by default? VTY lines console lines memory buffers Syslog server
Console lines
The amount o redundancy to incorporate into a network also affects what?
Cost
Factors that must be considered when selecting network devices:
Cost Speed and Types of Ports/Interfaces Expandability Operating System Features and Services
ISP-maintained DNS servers are assigned to SOHO customers via what?
DHCP
Which process failed if a computer cannot access the internet and recieved an IP address 169.254.142.5? HTTP DNS DHCP IP
DHCP
Dynamic Host Configuration Protocol (DHCP) is used by clients to acquire an IP a configuration (IE. IP address, subnet mask, default gateway and more) From a DHCP server.
DHCP Server
A user is unable to reach the website when typing http://www.cisco.com in a web browser, but can reach the same site by typing http://72.163.4.161. What is the issue? DNS TCP/IP protocol stack DHCP Default Gateway
DNS
Domain Name Services (DNS) resolves domain name to an IP address (e.g., cisco.com= 72.163.4.185) DNS provides the IP address of wen site (ie., domain name) to a requesting hosts
DNS Server
What layer of the OSI model does CDP run on?
Data Link Layer or Layer 2
What Windows 10 tool is used to determine which applications are using network services on a host? Control panel data usage file manager Windows Defender Firewall Windows Explorer
Data Usage
List of devices that use or comprise the network
Device Inventory
It is recommended that you plan, document, and maintain an IP addressing scheme based on what?
Device Type Example Default gateway (Router) 192.168.x.1 - 192.168.x.2192.168.x.0/30 Switches (max 2) 192.168.x.5 - 192.168.x.6192.168.x.4/30 Access points (max 6) 192.168.x.9 - 192.168.x.14192.168.x.8/29 Servers (max 6)192.168.x.17 - 192.168.x.22192.168.x.16/29 Printers (max 6)192.168.x.25 - 192.168.x.30192.168.x.24/29 IP Phones (max 6)1 92.168.x.33 - 192.168.x.38192.168.x.32/29 Wired devices (max 62) 192.168.x.65 - 192.168.x.126192.168.x.64/26 Wireless devices (max 62) 192.168.x.193 - 192.168.x.254192.168.x.192/26
The configured host name of a switch, router, or other device
Device identifiers
CDP exchanges hardware and software device information with its directly connected CDP neighbors. CDP provides the following information about each CDP neighbor device:
Device identifiers Address list Port identifier Capabilities list Platform
What are fixed configurations devices?
Devices that have a specific number and type of ports or interfaces and cannot be expanded.
What are some common issues you will face as a network admin?
Duplex Operation and Mismatch issues IP addressing issues on IOS devices IP addressing Issues on End Devices Default Gateway Issues Troubleshooting DNS
Email Servers and clients use Simple Mail Transfer Protocol (SMTP) to send emails Email clients use Post Office Protocol (POP3) or Internet Message Access Protocol (IMAP) to retrieve email. Recipients are specified using the [email protected] format
Email Server
What are two examples of network-aware application?
Email and web browsers
Devices that will factor into the IP addressing scheme include the following:
End user devices- The number and type of connection (ie wired, wireless, remote access) Servers and peripherals devices (eg printers and security cameras) Intermediary devices including switches and access points.
Among items to consider for network baselines are?
Error messages and the response times form host to host. If there is a considerable increase in response times. there may be latency issues to address.
IOS PING Indicators !
Exclamation mark indicates successful receipt of an echo reply message It validates a Layer 3 connection between source and destination
How do you use extended ping on Cisco IOS devices?
Extended ping is entered in privileged exec mode by typing ping without a destination IP address. You will then be given several prompts to customize the extended ping. Note: Pressing enter accepts the indicated default values
How do you use extended traceroute on a Cisco IOS device?
Extended traceroute is entered in privileged EXEC mode by typing in traceroute without a destination IP address. Note: Pressing enter accepts the indicated default values
File Transfer Protocol (FTP) service allows files to be downloaded and uploaded between client and FTP server FTP Secure (FTPS) and Secure FTP (SFTP) are used to secure FTP file exchange
FTP Server
What does autonegotiation do?
Facilitates configuration, minimizes problems and maximizes link performance between two interconnection Ethernet links. The connected devices first announce their supported capabilities and then choose the highest performance modes supported by both ends.
Give an example of how extended pin works.
For example, assume you wanted to test connectivity from the R1 LAN (i.e., 192.168.10.0/24) to the 10.1.1.0 LAN. This could be verified from the PC A. However, an extended ping could be configured on R1 to specify a different source address.. As illustrated in the example, the source IP address of the extended ping command on R1 could be configured to use the G0/0/1 interface IP address (i.e., 192.168.10.1).
What does CDP do to make it a security risk?
For example, by default many IOS versions send CDP advertisements out all enabled ports.
Where are IOS debug commands entered?
Privileged EXEC mode
True or False: The ping ipv6 command is used for IPv6 extended pings
True
True or False: Corporate networks should have extensive baselines
True, more extensive than we can describe in this course. Professional-grade software tools are available for storing and maintaining baseline information. In this course, we cover a few basic techniques and discuss the purpose of baselines.
Specifically, the ping command uses which layer 3 protocols to generate echo requests and echo reply messages?
Uses the Internet Control Message Protocol (ICMP) echo request (ICMP TYPE 8) and echo reply (ICMP TYPE 0) messages
What types of traffic would most likely have the highest priority through the network? FTP instant messaging Voice SNMP
Voice
To list a brief of all the debugging command options, what IOS privileged exec mode command do you use?
debug ?
Which two debug commands should you avoid using?
debug all and debug ip packet Commands such as debug all and debug ip packet generate a substantial amount of output and can use a large portion of system resources. The router could get so busy displaying debug messages that it would not have enough processing power to perform its network functions, or even listen to commands to turn off debugging.
What debug command can be used to show icmp messages?
debug ip icmp
What command on a Linux distro displays the status of the currently active interface and their IP configuration?
ifconfig
What command on a MAC OS can be used to verify the interface IP cofiguration?
ifconfig
to verify which protocols are operational
show protocols
To verify the current configuration and settings
show running-config
To verify the memory, interfaces, and licenses of the devices
show version
To stop logging messages on at terminal, use what privileged EXEC mode command?
terminal no monitor
What command is used on a Cisco device to perform a traceroute?
traceroute
What command is used on a Windows device is used to perform a traceroute?
tracert
A network technician is investigating network connectivity from a PC to a remote host with the address 10.1.1.5. Which command, when issued on a Windows PC, will display the path to the remote host? tracert 10.1.1.5 trace 10.1.1.5 ping 10.1.1.5 traceroute 10.1.1.5
tracert 10.1.1.5
To turn off all active debug commands at once, what privileged Exec mode command do you use?
undebug all
Physical and logical tpology
Network Documentaion
In order to maintain a high degree of reliability, _______ is required in the network design.
Redundancy
Ture of False: It is not always possible to type an IP address in nslookup and receive the domain name.
True, One of the most common reasons for this is that most websites run on serves that support multiple sites.
What factor should be considered in the design of a small network when devices are being chosen? cost of devices traffic analysis redundancy ISP
cost of devices
What is a network-aware application?
Meaning that they implement application layer protocols and are able to communicate directly with the lower layers of the protocol stack.
What features increase the cost of network devices?
Network management capabilities Embedded security technologies Optional advance switching technologies
This the first step in the troubleshooting process Although tools can be used in this step, a conversation with the users is often very helpful
Step 1 . Identify the Problem
What is troubleshooting?
Technicians must be able to analyze the problem and determine the cause of the error before they can resolve the network issues.
Which two network protocols are used to establish a remote access network connection to a device? (Choose two) File Transfer Protocol (FTP) Hypertext Transfer Protocol (HTTP) Remote Connect (RC) Secure Shell (SSH) Simple Mail Transfer Protocol (SMTP) Telnet
Telnet SSH
True or False? CDP will reveal the IP address of the neighbor regardless of whether or not you can ping that neighbor.
True
Ture of False: Although it is common for companies and organizations to manage their own DNS serves, any reachable DNS server can be used to resolve names.
True
Which factor must be considered when selecting network devices? color console connections cost elasticity
cosc
What IOS command or Windows would you use to see if the default gateway address was input correctly?
ip config for windows show ip route for Cisco routers
What command can you use to lookup what DNS server is in use by Windows computer?
ipconfig /all
What Windows command will display all of the cached DNS entries on a Windows Computer?
ipconfig /displaydns
What command on a Windows Devices is used to clear the arp cache?
netsh interface ip delete arpcache
Which element of scaling a network involves identifying the physical and logical topologies? device inventory cost analysis traffic analysis network documentation
network documentation
Which statement is true about CDP on a Cisco device? To disable CDP globally, the no cdp enable command in interface configuration mode must be used. Because it runs at the data link layer, the CDP protocol can only be implemented in switches. The show cdp neighbor detail command will reveal the IP address of a neighbor only if there is Layer 3 connectivity. CDP can be disabled globally or on a specific interface.
CDP can be disabled globally or on a specific interface.
To determine traffic flow patterns, it is important to do the following:
Capture traffic during peak utilization times to get a good representation of the different traffic types Perform the capture on different network segments and devices as some traffic will be local to a particular segment
A small company has only one router as the exit point to its ISP. Which solution could be adopted to maintain connectivity if the router itself, or its connection to the ISP, fails? Purchase a second least-cost link from another ISP to connect to this router. Add more interfaces to the router that is connected to the internal network. Have a second router that is connected to another ISP. Activate another router interface that is connected to the ISP, so the traffic can flow through it.
Have a second router that is connected to another ISP.
What are some issues that may be caused IP addressing issues on IOS devices?
IP address related problems will likely keep remote network devices from communicating, IP address conflicts, and routing problem.
What is does the extended traceroute do?
It allows the admin to adjust parameters related to the command operation.
What is the downside of using CDP?
It can also be security risk because it can provide useful network infrastructure information to threat actors.
What does the windows command ipconfig /release do?
It returns the DHCP leased IPV4 IP address
What happens if a device has an incorrect or nonexistent default gateway address?
It will not be able to communicate with devices in remote networks.
What are the two common causes of Incorrect IPv4 assignment to IOS devices?
Manual assignment mistakes and DHCP-related issues.
One of the most effective tools for monitoring and troubleshooting network performance is to establish a what?
Network Baseline
When will DNS be manually assigned vs automatically assigned?
Network admins are often responsible for manually assigning DNS server addresses on servers and other devices, while DHCP is used to automatically assign DNS server addresses to clients.
What is the IOS debug command used for?
OS processes, protocols, mechanisms and events generate messages to communicate their statuses. These messages can provide valuable information when troubleshooting or verifying system operations. Allows the administrator to display these messages in real-time for analysis. It is a very important tool for monitoring events on a Cisco IOS device. Note: The intent of the debug command is to capture live output for a short period of time (i.e., a few seconds to a minute or so). Always disable debug when not required.
Why would a Windows PC obtain a APIPA address?
Often, a computer will receive an APIPA address because DHCP is not working Something is wrong with the Default Gateway You ethernet cord could be broken or plugged out
One method for starting a baseline is to copy and paste the results form what network commands?
Ping, trace, or other relevant commands into a text file. These text files can be time stamped with the date and saved into an archive for later retrieval and comparison.
The hardware platform of the device for example , a Cisco 1841 series router
Platform
The name of the local and remote port in the form of an ASCII character string, such as Fast Ethernet 0/0
Port Idnetifire
What mechanism can be implemented in a small network to help minimize network latency for real-time streaming applications? ICMP PoE QoS AAA
QoS
What is required to classify traffic according to priority? IP addressing scheme quality of service (QoS) routing Switching
Quality of Service (QoS)
The network must support quality of service (QoS) mechanisms to minimize latency issues for real-time streaming applications Real-Time Transport Protocol (RTP) and Real-Time Control Protocol (RTCP) are two protocols that support this requirement.
Real-Time Applications
A common and efficient troubleshooting methodology is based on what?
Scientific method
Cisco offers OpenDNS which provides what?
Secure DNS service by filtering phishing and some malware sites.
To verify the list of known hosts on the local Ethernet LANs
Show arp
To verify the Layer 3 information of an interface
Show ip interface
What are some common Default Gateway issues?
Similar to IPv4 addressing issues, default gateway problems can be related to misconfiguration (in the case of manual assignment) or DHCP problems (if automatic assignment is in use).
Redundancy helps to eliminate what?
Single point failure
After the problem is identified, try to establish a theory of probable causes This step often yields more than a few probable causes to the problem
Step 2. Establish a Theory of Probable Causes
Based on the probable causes, test your theories to determine which one is the cause of the problem A technician will often apply a quick procedure to test and see of it solves the problem If a quick procedure does not correct the problem, you might need to research the problem further to establish the exact cause
Step 3. Tet the Theory to Determine Cause
After you have determined the exact cause of the problem, establish a plan of action to resolve the problem and implement the soulution.
Step 4. Establish a Plan of Action and Implement the Solution
After you have corrected the problem, verify full functionality. If applicable, implement preventive measures
Step 5. Verify Solution and Implement Preventive Measures
In the final step of the troubleshooting process, document your findings, actions, and outcomes This is very important for future references
Step 6. Document Findings, Actions, and Outcomes.
A technician is troubleshooting a network problem and has just established a theory of probable causes. What would be the next step in the troubleshooting process? Document findings, actions, and outcomes. Establish a plan of action and implement the solution Identify the problem Test the theory to determine cause Verify solution and implement preventive measures
Test the theory to determine cause
Why is the Cisco IOS command show cdp neighbors detail command helpful?
This command is very helpful when two Cisco routers cannot route across their shared data link. The command will help determine if one of the CDP neighbors has an IP configuration error
Why are debug messages not displayed on remote connections?
This is because debug messages are log messages which are prevented form being displayed on vty lines.
Why is it important that the CISCO IOS allows for narrowing the output of debug to include only the relevant feature or seubfeature.
This is important because debugging output is assigned high priority in the CPU process and it can render the system unusable. For this reason, use debug commands only to troubleshoot specific problems
The Cisco IOS offers an extended mode of the ping command. This mode allows you to do what?
This mode enables the user to create special type of pings by adjusting parameters related to the command operation.
The Cisco IOS extended traceroute options enables a user to do what?
To create a special type of trace by adjusting parameters related to the command operation.
Ture or False: CDP can only discover directly connected Cisco devices.
True
Ture or False: Data Usage tool is accessed using Settings > Network & Internet > Data usage > network interface (from the last 30 days).
True
Ture or False: Other operating systems, such Linux and OS X, will not assign an IPv4 address to the network interface if communication with a DHCP server fails.
True
True or False? When a Cisco device boots, CPD start by default?
True, CDP automatically discovers Cisco devices running CDP, regardless of which layer 3 protocol or suites are running.
True or False: Switches are available with additional ports for high-speed uplinks. Routers can be used to connect different types of networks.
True, Care must be taken to select the appropriate modules and interfaces for the specific media.
Ture or False: Most end devices are configured to rely on a DHCP server for automatic IPv4 address assignment.
True, If the device is unable to communicate with the DHCP server, then the server cannot assign an IPv4 address for the specific network and the device will not be able to communicate.
True or False: It is common for users to mistakenly relate the operation of an internet link to availability of the DNS.
True, User complaints such as the network is down or the internet is down are often caused by unreachable DNS server.
True or False: Certain IOS messages are automatically displayed on a console connection by not on a remote connection.
True, for instance, debug output is displayed by default on console connections. However, debug output is not automatically displayed on remote connections.
What simple network management tool can be used to analyze the network?
Wireshark
To turn of a specific debugging feature, what IOS privileged exec mode command do you use?
add the no keyword in front of the debug command or you can enter the undebug form of the command EX: no debug ip icmp EX: undebug ip icmp
When should an admin establish a network baseline? at regular intervals over a period of time when the traffic is at peak in the network at the lowest point of traffic in the network when there is a sudden drop in traffic
at regular intervals over a period of time
What command on a Linux distro is used to display addresses and their properties and can be used to add or delete IP addresses?
ip address
What Windows command would you use to verify that the IP addressing information is correct?
ip config ip config /all
Do not resolve address to hostnames
-d
Maximum number of hops to search for target
-h maximun_hops
Small networks typically provide a single exit point toward the internet via one or more default gateways. If the router fails, the entire network loses connectivity to the internet. For this reason, it may be advisable to do what?
For a small business to pay for a second service provider as backup.
An IP phone performs voice-to-IP conversion with the use of dedicated server for call control and signaling. Many vendors provide small business IP telephony such as Cisco Business Edition 4000 series products
IP Telephony
Why is the Windows 10 Data Usage Tool useful?
It is useful because it determines which applications are using network services on a host.
Network devices must have operating systems that can support the organizations requirements such as the following:
Layer 3 switching Network Address Translation (NAT) Dynamic Host Configuration Protocol (DHCP) Security Quality of Service (QoS) Voice over IP (VoIP)
What are modular devices?
Modular devices have expansion slots to add new modules as requirements evolve.
Applications are the software programs used to communicate over the network. Some end-user applications are network-aware, meaning that they implement application layer protocols and are able to communicate directly with the lower layers of the protocols stack. Email clients and web browsers are examples of this type of application.
Network Applications
There are two forms of software programs or processes that provide access to the network:
Network Applications Application layer services
SSH is used to establish a secure remote access connection between an SSH client and other SSH-enabled devices:
Network Device- The network device (e.g., router, switch, access point etc.) must support SSH to provide remote access SSH server services to clients Server- The server (e.g., web server, email server, etc.) must support remote access SSH server services to clients
To scale a network, several elements are required:
Network documentation Device Inventory Budget Traffic Analysis Note: These elements are used to inform the decision-making that accompanies the scaling of a small network
Network Utilization Tools can be used to capture an snapshot of information such as the following:
OS and OS version CPU utilization RAM utilization Drive utilization Non-Network applications Network Applications
This analysis can be sued to make decisions on how to manage the traffic more efficiently. This can be done by doing what?
Reducing Unnecessary traffic flows Changing flow patterns altogether by moving a server Note: Sometimes, simply relocating a server or service to another network segment improves network performance and accommodates the growing traffic needs. At other times, optimizing the network performance requires major network redesign and intervention.
What can extended traceroute be used to troublshoot?
Routing loops, determining the exact next-hop, router, or determining where packets are getting dropped or denied by a router or firewall.
If your network is for small business, presumably, you want that business to grow, an your network to grow along with it. This is known as what?
Scaling netowrk
Network administrators commonly require access to network devices and servers. The two most common remote access solutions are what?
Secure Shell (SSH) and Telnet
Choosing the number and type of ports on a router or switch is a critical decision. Newer computer have built-in 1Gbps NICs. Some servers may even have 10Gbps ports. Although it is more expensive, choosing Layer 2 devices that can accommodate increased speeds allows the network to evolve without replacing central devices.
Speed and Types of Ports/Interfaces
Many operating systems provide built-in tools to display network utilization. For example, a Windows host provides tools such as:
Task Manager Event Viewer Data Usage Tools
Each application layer or network service uses protocols, which define what?
The standards and data formats to be used Without protocols, the data network would not have a common way to format and direct data. In order to understand the function of various network services, it is necessary to become familiar with the underlying protocols that govern their operation.
As the network grows, it becomes important to determine how to manage network traffic. It is important to understand what about the network?
The type of traffic that is crossing the network as well as the current traffic flow.
Windows implementation of traceroute (tracert) sends ICMP echo requests. What does Cisco IOS and Linux use?
They use UDP with an invalid port number. The final destination will return an ICMP port unreachable message
VoIP devices convert analog telephone signals into digital IP packets Typically, VoIP is less expensive than IP telephony solution, but the quality of communications does not meet the same standards. Small network voice and video over IP ca be solved using Skype and non-enterprise versions of Cisco WebEx.
VoIP
Which software installed on key hosts can reveal the types of network traffic flowing through the network? Linux Windows MacOS SSH Wireshark
Wireshark
Which elements are required to scale to a larger network? (Choose two) Budget device configuration increased bandwidth network documentation windows hosts
budget network documentation
How do you interrupt a traceroute on Windows?
ctrl-c
How do you interrupt a traceroute on Cisco IOS?
ctrl-shift-6
