Configuring and Troubleshooting Networks

Network Setup and Tools

Configuring a Wired SOHO Network

What is a SOHO Network?

A SOHO (small office, home office) network is a LAN with less than 10 computers that serves a small physical space with a few employees or home users.

It can be a wired Ethernet LAN or a LAN made of both wired and wireless devices.

A typical wired SOHO network includes:

• Router with a firewall
• Switch with 4-8 Ethernet LAN ports
• Printer

• Desktops and /or laptops

  

Setup steps – plan ahead

When setting up a SOHO network, knowing the compatibility requirements is very important.

• Before setting up any SOHO network, review and confirm everything in your plan to ensure a successful installation.

  

Setup steps – gather hardware

• SOHO networks need a switch to act as the hub of the network

• If Internet is desired, a router can be added or used instead

  

Setup steps – connect hardware

Setup steps – router settings

Log in to router settings

• Enter ‘ipconfig’ in a command prompt window to find your router’s public IP address (listed next to default gateway)

• Enter it into a browser and log in

  Update username and password

• All routers have default administrator usernames and passwords

• To improve security, change the default username password

  Update firmware

• Updating router firmware solves problems and enhances security
• Check the manufacturer website for available firmware updates
• Download and install if your firmware is not up-to-date

Setup steps – additional settings

• SOHO wired network security depends on a firewall
• Most routers have a built-in firewall, additional software can be installed on individual machines
• Servers and hardware have built-in DHCP and NAT actions
• DHCP servers use IP addresses to provide network hosts
• NAT maps public IPv4 address to private IP addresses

Setup steps – user accounts

User account setup is included in most operating systems.

Setup steps – test connectivity

Network performance depends on Internet strength, cable specification, installation quality, connected devices, and network and software settings.

Test and troubleshoot to ensure proper network performance.

To troubleshoot performance:

• Run security tools
• Check for updates
• Restart devices
• Run diagnostic
• Reboot the router or modem

Configuring a (wireless) SOHO network

What is a SOHO wireless network?

A SOHO wireless network is a WLAN that serves a small physical space with a few home users.

A SOHO wireless network can be configured with the help of a central WAP, which can cover a range of wireless devices within a small office or home.

Common broadband types

Common broadband types that enable network connection:

• DHCP:
  • The most common broadband type, used in cable modem connections.
• PPPoE:
  • Used in DSL connections in areas that don’t have newer options.
• Static IP:

  • More common in business.

    DHCP is the easiest broadband type to use. Internet Service Providers can provide other options if needed.

Wireless security factors

Wireless networks can be setup to be either open (unencrypted) or encrypted.

Get to know your wireless router

Connect to router admin interface

To manage router settings, you must find its default IP address, paste it into a browser and hit enter.

Assign a SSID

• SSID is the name of a wireless network.
• This name is chosen during setup.
• Unique names help to identify the network.
• Each country determines band and available modes.
• 2.4 GHz and 5 GHz have specific supported modes.
• Every router has as a default option.

Wireless encryption security modes

Going wireless

Once the router is configured, your wireless network is ready.

Users will see it among the available wireless networks when they click the Wi-Fi icon.

Test and troubleshoot connectivity

Test network performance and Internet connectivity on each wireless device in the vicinity of the WAP.

If required, troubleshoot performance issues (network lags, glitches, or network cannot be accessed) with the following actions:

• Check router configuration settings.
• Run security tools.
• Check for updates.
• Restart devices.
• Run diagnostics.
• Reboot the router or modem.
• Check equipment for damage.

Mobile configuration

IMEI vs. IMSI

IMEI and IMSI are used to identify cellular devices and network users when troubleshooting device and account issues.

Internation Mobile Equipment Identity (IMEI)

• ID# for phones on GSM, UMTS, LTE, and iDEN networks

• Can be used to block stolen phones

  International Mobile Subscriber Identity (IMSI)

• ID# for cell network subscribers
• Stored in a network sim card

Troubleshooting Network Connectivity

Symptoms of connectivity problems

“Can’t connect” or “slow connection” are two of the most common network problems. These symptoms can be caused by several things.

Causes of Connectivity Problems

Common causes of network connectivity problems:

Cable Damage

Cable damage slows or stops network connections. The damage can be obvious or hidden from view.

Ways to solve:

• Check for physical damage
• Test the cable using different devices or a specialized tool
• Replace the cable

Equipment malfunction

An equipment malfunction can slow or stop network connections.

Ways to solve:

• Check network adapter drivers in Device Manager
• Check switch or router port settings in the management software
• Replace the equipment

Out of range

When a user is too far away from a wireless signal, their connection will lag or fail.

Ways to solve:

• Move physically closer to the source of the wireless connection
• Move the wireless connection source closer to the affected user(s)
• Use stronger devices to boost the signal strength
• Use more devices to ensure the Wi-Fi reaches users who are farther away

Missing SSID

Network connections can fail when a user can’t find the network name (SSID) in the available networks list.

Ways to solve:

• Move physically closer to the Wi-Fi source
• Reconfigure the network to ensure the SSID is not hidden
• Upgrade devices or use compatibility mode on newer network, so older devices can still connect
  • Compatibility mode can slow a network
  • Reserve 2.4 GHz band for legacy devices

Interference

Interference is when a radio or microwave signal slows or breaks a wireless connection.

Ways to solve:

• Remove the source of the interference signal
• Use a different Wi-Fi frequency (wireless)
• Use shielded cables to connect (wired)
• Remodel the building with signal-blocking materials

Weak signal strength

When signal strength is weak, a wireless adapter might slow speeds down to make the connection more reliable.

Weak signals cause:

• Lags
• Dropped connection
• Back-and-forth network hopping
• Out of range
• Interference

• Physical obstacles

  Ways to solve:

• Move closer to signal
• Adjust Wi-Fi frequency

• Realign router antennae

  Wireless access points should be placed up high and in the middle of the space.

DNS and software configuration

Network connections can fail when DNS or software is configured incorrectly.

DNS issue:

• Domain not recognized

• IP addresses recognized

  OS and apps issue:

• Software affecting connection

  Ways to solve:

• For DNS servers, test domains using ipconfig in a command prompt
• For apps and OSes, use the network troubleshooter in Windows Settings

Malware

Malware slows or stops network connections intentionally, or as a result of overloading a system with other tasks.

Ways to solve:

• Use antimalware tools
• Adjust firewall settings
• Configure Privacy settings
  • Windows
  • Browser
  • Email

Network Troubleshooting with Command Line Utilities

Common command line utility commands that you would use to troubleshoot or diagnose network issues:

• ipconfig
  • IP address
  • Subnet mask
  • Default gateway
• ping
  • You can ping:
    • IP addresses, or
    • Domains
• nslookup
  • It lists:
    • Your DNS server
    • Your DNS server’s IP address
    • Domain name
• tracert
  • Tracert lists:
    • Sent from
    • Sent to
    • Number of transfers
    • Transfer locations
    • Duration
• netstat: It shows if a server’s email and ports are open and connecting to other devices.
  • Netstat lists:
    • Protocol
    • Local address
    • Foreign address
    • Current state