Objective 1.2 Compare and contrast the use of networking services and applications. Flashcards
VPN
A virtual private network (VPN) extends a private network across a public network, such as the Internet. It enables users to send and receive data across shared or public networks as if their computing devices were directly connected to the private network, and thus benefit from the functionality, security and management policies of the private network.[1] A VPN is created by establishing a virtual point-to-point connection through the use of dedicated connections, virtual tunnelling protocols, or traffic encryption.
Site to Site VPN
Site-to-site VPNs connect entire networks to each other – for example, connecting a branch office network to a company headquarters network. In a site-to-site VPN, hosts do not have VPN client software; they send and receive normal TCP/IP traffic through a VPN gateway.
Host to Site
Remote access VPNs connect individual hosts to private networks – for example, travelers and teleworkers who need to access their company’s network securely over the Internet. In a remote access VPN, every host must have VPN client software (more on this in a minute). Whenever the host tries to send any traffic, the VPN client software encapsulates and encrypts that traffic before sending it over the Internet to the VPN gateway at the edge of the target network. Upon receipt, that VPN gateway behaves as described above for site-to-site VPNs. If the target host inside the private network returns a response, the VPN gateway performs the reverse process to send an encrypted response back to the VPN client over the Internet.
Host to Host
A host-to-host IPsec connection is an encrypted connection between two systems, both running IPsec with the same authentication key. With the IPsec connection active, any network traffic between the two hosts is encrypted.
IPsec
Internet Protocol Security (IPsec) is a protocol suite for secure Internet Protocol (IP) communications by authenticating and encrypting each IP packet of a communication session.
GRE
Generic Routing Encapsulation (GRE) is a tunneling protocol developed by Cisco Systems that can encapsulate a wide variety of network layer protocols inside virtual point-to-point links over an Internet Protocol network.
SSL VPN
An SSL VPN (Secure Sockets Layer virtual private network) is a form of VPN that can be used with a standard Web browser. In contrast to the traditional Internet Protocol Security (IPsec) VPN, an SSL VPN does not require the installation of specialized client software on the end user’s computer.
PPTP
he Point-to-Point Tunneling Protocol (PPTP) is a method for implementing virtual private networks. PPTP uses a control channel over TCP and a GRE tunnel operating to encapsulate PPP packets.
PTP
The Precision Time Protocol (PTP) is a protocol used to synchronize clocks throughout a computer network. On a local area network, it achieves clock accuracy in the sub-microsecond range, making it suitable for measurement and control systems.
TACACS
Terminal Access Controller Access-Control System (TACACS, usually pronounced like tack-axe) refers to a family of related protocols handling remote authentication and related services for networked access control through a centralized server. The original TACACS protocol, which dates back to 1984, was used for communicating with an authentication server, common in older UNIX networks; it spawned related protocols:
RADIUS
Remote Authentication Dial-In User Service (RADIUS) is a networking protocol that provides centralized Authentication, Authorization, and Accounting (AAA or Triple A) management for users who connect and use a network service.
RAS
Remote Access Services (RAS) refers to any combination of hardware and software to enable the remote access tools or information that typically reside on a network of IT devices. Remote Access Service (RAS) connects a client to a host computer, known as a remote access server.
Web Services
A Web service is a service offered by an electronic device to another electronic device, communicating with each other via the World Wide Web. In a Web service, Web technology such as the HTTP, originally designed for human-to-machine communication, is utilized for machine-to-machine communication, more specifically for transferring machine readable file formats such as XML and JSON. In practice, the Web service typically provides an object-oriented Web-based interface to a database server, utilized for example by another Web server, or by a mobile application, that provides a user interface to the end user. Another common application offered to the end user may be a mashup, where a Web server consumes several Web services at different machines, and compiles the content into one user interface.
Unified Voice Services
Skype, Lync, VoIP, connecting various services to each other.
Network Controllers
A network interface controller (NIC, also known as a network interface card, network adapter, LAN adapter or physical network interface,[1] and by similar terms) is a computer hardware component that connects a computer to a computer network.
Modern network interface controllers offer advanced features such as interrupt and DMA interfaces to the host processors, support for multiple receive and transmit queues, partitioning into multiple logical interfaces, and on-controller network traffic processing such as the TCP offload engine.
