Category Archives: networking

cURL for port scanning

Usually such tools as telnet, nmap or nc are used to find listening remote ports. However nmap and netcat are not included in default Linux installation, telnet is good for manual testing and is not friendly for scripting task. So sometime I am using cURL or wget to get information about open ports on remote… Read More »

Ping in Network Discovery

Network discovery is a process to find other computers and devices on some network and to get obtainable information about them. The discovery procedure is based on sending out request messages over and analyzing responses from remote devices. ICMP (Internet Control Message Protocol) is most frequently method detect remote device. Below is presented simple Linux… Read More »

Dive into WHOIS protocol

WHOIS is a TCP-based query/response protocol which is used to get information about registered domain names, domain name servers, registrar, creation and paid till date. Also it may contain data about domain owner and/or owner’s contact requisites. Default tcp port of WHOIS protocol is 43. The WHOIS client send a text request to the WHOIS… Read More »

Private and Public keys generation and usage for CentOS

Public and private key pair is alternative way of server logging using Secure Shell (SSH) protocol. It gives possibility to avoid user name and password prompts so could be faster and more comfortable. Besides both keys represent two long string of characters, so eventually it is more difficult to crack. There are a lot of… Read More »

Installation and configuration of net-snmp agent on CentOS Linux.

SNMP v3 is the version of Simple Network Management Protocol with advance security mechanism to handle SNMP packets. The net-snmp agent is free snmp v3 agent. The version 3 of Simple Network Management Protocol provides more secure authentication and cryptographic features. The snmpv3 defined in RFCs 3413 and 3414. The steps presented below related to… Read More »