Software Troubleshooting Tools
While troubleshooting software issues in any network, different type of tools and techniques are used. Some of them are discussed as follows:
Packet Sniffer: It is a tool used to troubleshoot network problems. F intercepts data flow in a network and therefore, mostly hackers use this tool to enter a network.
Port Scanner: It is a tool used to check the open ports on a network. The technicians and administrators use this tool to ensure the security network against any cyberattack.
The result of a port scan can be divided into three categories:
- Open or Accepted: In this category, the host replies to indicate that a service is listening on the port.
- Closed or Denied: In this category, the host replies to indicate that connection request is denied to the port.
- Filtered, Dropped or Blocked: In this category, the host does not reply.
Wi-Fi Analyzer: It is a device that locates and analyses wireless traffic. Further, it can either be a handheld device, or software installed on a laptop. In addition, it can also detect and analyse Wi-Fi signals.
Bandwidth Speed Tester: Bandwidth speed test determines the speed of a network during a short period. This test measures the performance of a network by sending and receiving data packets over a network. it requires two factors to calculate the performance namely, amount of data transmitted, and time required for data transmission.
There are various online bandwidth speed tester available such as www. speediest. net and www.bandwidthplace.com. These type of online test provides different information such as upload speed, download speed and ping.
Command line: command line tools are small programs or scripts which are designed to perform a specific function. For instant, there are some command line such as ping, ipconfig, and iptables, which are used to troubleshoot software issue.
Ping: Ping (Packet Internet Groper) command enables to verity the ability of a computer system to reach a destination computer. It transmits ICMP (Internet Control Message Protocol) echo request message to the destination computer and waits for a reply. The output of ping command shows average, minimum and maximum time taken by a packet to find its destination computer.
tracert/traceroute command: It is a command-line tool or utility program that traces the route to a destination host and provides a list of network hops between the host computer and the destination computer.
‘tracert’ is the short form of ‘trace route’ is used in the Windows based operating system. On the other hand, `trace -route’ is used in the Unix operating system and shows the different IP addresses through which a packet is routed to reach the destination. Further, it also displays the number of hops required to reach the destination.
nsiookup ns lookup is a useful command for verifying DNS configuration and troubleshooting DNS issues such as hostname resolution. It displays the hostname and IP address of the DNS server for the local host. Also, it will display a command prompt for further queries. User can type a question mark (?) or help and then press Enter to see all available commands.
ipconfig; In Windows OS, the ipconfig command is a useful tool that displays the information of a network. It displays the IP address, subnet mask, router’s IP address (also referred as a default gateway) for all network adapters. User can use ipconfig/al I command to get a detailed information on his/her LAN connection.
ifconfig: ifconfig (interface configuration) is a Linux/UNIX command used to view and manage the configuration of a network interface on a computer system.
iptables: Data is transmitted over the Internet in the form of packets. Both incoming and outgoing traffic packets can be filtered with the help of ip tables. The ip tables can be defined as the set of rules which specify the function that needs to be performed when a packet matches with the rules. iptables which is a Linux firewall utility and the command line application is used to set-up and maintain these tables and packet filtering.
netstat: The netstat (network statistics) command is used to check the active network status on a local host. It provides information about the active TCP/IP network connection, TCP/IP port and statistics of the used protocols. User can apply the netstat command to find out the number of packets sent and received.
tcpdump: It was designed by Van Jacobson, Sally Floyd, Vern Paxson and Steven McCanne in 1988 at Lawrence Berkeley Laboratory of Network Research Group.
tcpdump can be defined as a packet analyser and a command line utility which enable a user to view and monitor data packets during data transmission between the network and his computer system. In addition, it can read data packets from a network interface card and write packets to an existing file.
pathping: It is the TCP/IP utility which enables a user to retrieve necessary information such as network latency and network loss at intermediate hops between a source and destination address. Pathping transmits multiple ICMP (Internet Message Control Protocol) echo request messages and then analyses the results to retrieve information.
Nmap: Nmap (Network Mapper) was designed by Gordon Lyon in September 1997. Nmap is an open source software and security scanner used to find a host and services on a network. The GUI version of Nmap is Zenmap and is vastly used to understand the characteristics of any target network.