In computing, traceroute and tracert are diagnostic command-line interface commands for displaying possible routes (paths) and transit delays of packets across an Internet Protocol (IP) network.
In computer science, interprocess communication (IPC), are the mechanisms provided by an operating system for processes to manage shared data. Typically, applications can use IPC, categorized as clients and servers, where the client requests data and the server responds to client requests. Many applications are both clients and servers, as commonly seen in distributed computing.
The Network Time Protocol (NTP) is a networking protocol for clock synchronization between computer systems over packet-switched, variable-latency data networks. In operation since before 1985, NTP is one of the oldest Internet protocols in current use. NTP was designed by David L. Mills of the University of Delaware.
nslookup is a network administration command-line tool for querying the Domain Name System (DNS) to obtain the mapping between domain name and IP address, or other DNS records.
In computing, netstat is a command-line network utility that displays open network sockets, routing tables, and a number of network interface and network protocol statistics. It is available on Unix, Plan 9, Inferno, and Unix-like operating systems including macOS, Linux, Solaris and BSD. It is also available on IBM OS/2 and on Microsoft Windows NT-based operating systems including Windows XP, Windows Vista, Windows 7, Windows 8 and Windows 10.
Clock synchronization is a topic in computer science and engineering that aims to coordinate otherwise independent clocks. Even when initially set accurately, real clocks will differ after some amount of time due to clock drift, caused by clocks counting time at slightly different rates. There are several problems that occur as a result of clock rate differences and several solutions, some being more acceptable than others in certain contexts.
In the X Window System, an X display manager is a graphical login manager which starts a login session on an X server from the same or another computer.
OpenNTPD is a Unix daemon implementing the Network Time Protocol to synchronize the local clock of a computer system with remote NTP servers. It is also able to act as an NTP server to NTP-compatible clients.
The Time Protocol is a network protocol in the Internet Protocol Suite. Its purpose is to provide a site-independent, machine readable date and time.
The Network Time Protocol daemon (ntpd) is an operating system program that maintains the system time in synchronization with time servers using the Network Time Protocol (NTP).
NetworkManager is a daemon that sits on top of libudev and other Linux kernel interfaces and provides a high-level interface for the configuration of the network interfaces.
Network Access Protection (NAP) is a Microsoft technology for controlling network access of a computer, based on its health. It was first included in Windows Vista and Windows Server 2008 and backported to Windows XP Service Pack 3. With NAP, system administrators of an organization can define policies for system health requirements. Examples of system health requirements are whether the computer has the most recent operating system updates installed, whether the computer has the latest version of the anti-virus software signature, or whether the computer has a host-based firewall installed and enabled. Computers with a NAP client will have their health status evaluated upon establishing a network connection. NAP can restrict or deny network access to the computers that are not in compliance with the defined health requirements.
WHOIS is a query and response protocol that is used for querying databases that store an Internet resource's registered users or assignees. These resources include domain names, IP address blocks and autonomous systems, but it is also used for a wider range of other information. The protocol stores and delivers database content in a human-readable format. The current iteration of the WHOIS protocol was drafted by the Internet Society, and is documented in RFC 3912.
Misuse of a Network Time Protocol (NTP) server ranges from flooding it with traffic or violating the server's access policy or the NTP rules of engagement. One incident was branded NTP vandalism in an open letter from Poul-Henning Kamp to the router manufacturer D-Link in 2006. This term has later been extended by others to retroactively include other incidents. There is, however, no evidence that any of these problems are deliberate vandalism. They are more usually caused by shortsighted or poorly chosen default configurations.
gpsd is a computer software program that collects data from a Global Positioning System (GPS) receiver and provides the data via an Internet Protocol (IP) network to potentially multiple client applications in a server-client application architecture. Gpsd may be run as a daemon to operate transparently as a background task of the server. The network interface provides a standardized data format for multiple concurrent client applications, such as Kismet or GPS navigation software.
On Unix-like operating systems, rdate is a tool for querying the current time from a network server and, optionally, setting the system time. Rdate uses the Time Protocol. The Time Protocol is generally considered obsolete and has been replaced by the Network Time Protocol (NTP).
OpenSSH is a suite of secure networking utilities based on the Secure Shell (SSH) protocol, which provides a secure channel over an unsecured network in a client–server architecture.
timed is an operating system program that maintains the system time in synchronization with time servers using the Time Synchronization Protocol (TSP) developed by Riccardo Gusella and Stefano Zatti. Gusella and Zatti had done earlier related work on their TEMPO algorithm. The Time Synchronization Protocol specification refers to an election algorithm and a synchronization mechanism specified in other technical reports listed as "to appear".
chrony is an implementation of the Network Time Protocol (NTP). It is an alternative to ntpd, a reference implementation of NTP. It runs on Unix-like operating systems and is released under the GNU GPL v2. It is the default NTP client and server in Red Hat Enterprise Linux 8 and SUSE Linux Enterprise Server 15, and available in many Linux distributions.
A domain controller (DC) is a server that responds to security authentication requests within a computer network domain. It is a network server that is responsible for allowing host access to domain resources. It authenticates users, stores user account information and enforces security policy for a domain. It is most commonly implemented in Microsoft Windows environments, where it is the centerpiece of the Windows Active Directory service. However, non-Windows domain controllers can be established via identity management software such as Samba and Red Hat FreeIPA.
