Network control protocol
The function of multi-link PPP is that it allows an enterprise to connect to multiple ISPs.
The most common WAN data-link protocols are: 1. HDLC 2. PPP 3. Frame Relay 4. ATM
HDLC - High level data link control used in conjunction with Networking protocols like PPP (point-to-point) protocol. According to RFC 1662, PPP uses HDLC like frame by providing address and control fields. For PPP these fields are constants 0xFF and 0x03.
PPP (Point-to-Point Protocol) has several advantages over HDLC (High-Level Data Link Control) for serial communications, primarily its support for multiple network layer protocols, allowing for more flexible and versatile connections. Additionally, PPP includes built-in mechanisms for authentication, error detection, and link quality monitoring, enhancing security and reliability. Its ability to negotiate link parameters dynamically also enables better configuration during connection establishment compared to HDLC's more rigid structure.
The data link layer, which is the second layer of the OSI model, includes protocols such as Ethernet, Point-to-Point Protocol (PPP), and High-Level Data Link Control (HDLC). Ethernet is widely used for local area networks (LANs), while PPP is commonly used for direct connections between two network nodes. Additionally, protocols like Wi-Fi (IEEE 802.11) also operate at this layer, facilitating wireless communication. These protocols handle framing, addressing, and error detection for data transmitted over physical media.
During a PPP (Point-to-Point Protocol) connection, the NCP (Network Control Protocol) provides two main functions: it establishes and configures the network layer protocols used over the link, and it manages the negotiation of options for these protocols. NCP allows different network layer protocols to operate simultaneously over the same link by encapsulating their packets. Additionally, it facilitates the dynamic assignment of IP addresses and other necessary parameters for the network layer.
Application: FTP, SMTP, HTTP Transport : TCP, UTP Network : IP, routing protocols Link : PPP ethernet Physical : bit
Data link layer protocols like PPP and HDLC define how data is encapsulated for transmission across a WAN link.
NCP (Network Control Protocol) is responsible for negotiating and configuring the network-layer parameters of a PPP (Point-to-Point Protocol) session. It establishes and manages the network control options needed for the successful communication between the two endpoints of the PPP link. NCP allows for the customization of network protocols and parameters to suit the specific requirements of the PPP connection.
You need to use a protocol that will translate serial protocol (your modem) to a packet based network. Protocols such as SLIP, PPP, PPTP are used for that purpose.
Internet (PPP) Accounts A PPP (Point-to-Point Protocol) account is an Internet account that uses the PPP communications protocol. PPP is the most popular type of Internet account because the most popular software--Internet Explorer, Netscape Navigator, Outlook Express, Eudora, and other programs--is designed to work with PPP accounts. Occasionally, you may run into a SLIP (Serial Line Internet Protocol) or CSLIP account (Compressed SLIP), which are old, less-reliable protocols than PPP, but which work the same way. This book refers to PPP, CSLIP, and SLIP accounts as dial-up Internet accounts. An Internet service provider (ISP) is an organization that provides Internet accounts, usually PPP accounts, but occasionally UNIX shell accounts. All ISPs provide dial-in accounts using regular phone lines, and many also provide ISDN and DSL connections
A PPP adapter, or Point-to-Point Protocol adapter, is a device or software component that facilitates the establishment of a direct connection between two network nodes over a serial link. It enables the encapsulation of network layer protocols, such as IP, for transmission over point-to-point links. Commonly used in dial-up connections and virtual private networks (VPNs), the PPP adapter supports features like authentication, encryption, and compression to enhance data transmission.