In computing, the Post Office Protocol (POP) is an application-layer Internet standard protocol used by e-mail clients to retrieve e-mail from a mail server.
The Session Initiation Protocol (SIP) is a signaling protocol used for initiating, maintaining, and terminating real-time sessions that include voice, video and messaging applications. SIP is used for signaling and controlling multimedia communication sessions in applications of Internet telephony for voice and video calls, in private IP telephone systems, in instant messaging over Internet Protocol (IP) networks as well as mobile phone calling over LTE (VoLTE).
An email client, email reader or more formally mail user agent (MUA) is a computer program used to access and manage a user's email.
In computer networks, a proxy server is a server that acts as an intermediary for requests from clients seeking resources from other servers. A client connects to the proxy server, requesting some service, such as a file, connection, web page, or other resource available from a different server and the proxy server evaluates the request as a way to simplify and control its complexity. Proxies were invented to add structure and encapsulation to distributed systems.
Squid is a caching and forwarding HTTP web proxy. It has a wide variety of uses, including speeding up a web server by caching repeated requests, caching web, DNS and other computer network lookups for a group of people sharing network resources, and aiding security by filtering traffic. Although primarily used for HTTP and FTP, Squid includes limited support for several other protocols including Internet Gopher, SSL, TLS and HTTPS. Squid does not support the SOCKS protocol.
SOCKS is an Internet protocol that exchanges network packets between a client and server through a proxy server. SOCKS5 additionally provides authentication so only authorized users may access a server. Practically, a SOCKS server proxies TCP connections to an arbitrary IP address, and provides a means for UDP packets to be forwarded.
NetWare is a discontinued computer network operating system developed by Novell, Inc. It initially used cooperative multitasking to run various services on a personal computer, using the IPX network protocol.
In computer networking, port forwarding or port mapping is an application of network address translation (NAT) that redirects a communication request from one address and port number combination to another while the packets are traversing a network gateway, such as a router or firewall. This technique is most commonly used to make services on a host residing on a protected or masqueraded (internal) network available to hosts on the opposite side of the gateway, by remapping the destination IP address and port number of the communication to an internal host.
An open proxy is a proxy server that is accessible by any Internet user. Generally, a proxy server only allows users within a network group to store and forward Internet services such as DNS or web pages to reduce and control the bandwidth used by the group. With an open proxy, however, any user on the Internet is able to use this forwarding service.
netcat is a computer networking utility for reading from and writing to network connections using TCP or UDP. The command is designed to be a dependable back-end that can be used directly or easily driven by other programs and scripts. At the same time, it is a feature-rich network debugging and investigation tool, since it can produce almost any kind of connection its user could need and has a number of built-in capabilities.
In computer networks, a tunneling protocol is a communications protocol that allows for the movement of data from one network to another. It involves allowing private network communications to be sent across a public network through a process called encapsulation.
A web accelerator is a proxy server that reduces web site access time. They can be a self-contained hardware appliance or installable software.
Network transparency, in its most general sense, refers to the ability of a protocol to transmit data over the network in a manner which is transparent (invisible) to those using the applications that are using the protocol. In this way, users of a particular application may access remote resources in the same manner in which they would access their own local resources. An example of this is cloud storage, where remote files are presented as being locally accessible, and cloud computing where the resource in question is processing.
Push notifications are small messages that can reach audiences anywhere and anytime. There’s a difference between pop-ups and push notifications. Pop-ups appear only when audiences are on the site they belong to. Push messages are independent of sites. They are associated with web browsers and apps.
A proxy auto-config (PAC) file defines how web browsers and other user agents can automatically choose the appropriate proxy server for fetching a given URL.
In computer networking, a port is an endpoint of communication. Physical as well as wireless connections are terminated at ports of hardware devices. At the software level, within an operating system, a port is a logical construct that identifies a specific process or a type of network service. Ports are identified for each protocol and address combination by 16-bit unsigned numbers, commonly known as the port number. Inbound packets are received, and the port number in the header is used to decide which application is to be passed the packets.
The X-Forwarded-For (XFF) HTTP header field is a common method for identifying the originating IP address of a client connecting to a web server through an HTTP proxy or load balancer.
yProxy is a Network News Transfer Protocol (NNTP) proxy server for the Windows operating system. yProxy's main function is to convert yEnc-encoded attachments to UUE-encoded attachments on the fly. The main purpose of this is to add functionality to NNTP newsreaders that do not have native support for yEnc.
The inventor of yEnc recommends yProxy for use by Windows users whose newsreaders do not support yEnc decoding.
Since Internet users and system administrators have deployed a vast array of techniques to block, filter, or otherwise banish spam from users' mailboxes and almost all Internet service providers forbid the use of their services to send spam or to operate spam-support services, special techniques are employed to deliver spam emails. Both commercial firms and volunteers run subscriber services dedicated to blocking or filtering spam.
