| A | B |
|---|
| Without a Layer 2 protocol, the physical WAN links have no mechanism to | transmit data and implement flow control. |
| Serial Line Internet Protocol (SLIP) was limiting the Internet's growth | PPP was created to solve remote Internet connectivity problems. |
| PPP was needed to be able to | dynamically assign IP addresses and allow for use of multiple protocols. |
| PPP provides router-to-router and host-to-network connections over both | synchronous and asynchronous circuits. |
| used by PPP for encapsulating datagrams over point-to-point links. | High-Level Data Link Control (HDLC) |
| used by PPP for establishing, configuring, and testing the data-link connection. | Link Control Protocol (LCP) |
| used by PPP for establishing and configuring different network-layer protocols | Network Control Protocols (NCPs) |
| PPP is designed to allow the simultaneous use of | multiple network-layer protocols. |
| PPP supports | IP, IPX, Apple Talk |
| With its lower-level functions, PPP can use | Synchronous physical media and Asynchronous physical media |
| Synchronous physical media | those that connect Integrated Services Digital Network (ISDN) networks |
| Asynchronous physical media | those that use basic telephone service for modem dialup connections |
| With its higher-level functions, PPP supports or encapsulates several network-layer protocols with NCPs that include | BCP, IPCP, and IPXCP |
| PPP frame field that Indicates the beginning or end of a frame | Flag |
| PPP frame field that Consists of the standard broadcast address | Address |
| PPP frame field that identify the protocol encapsulated in the data field of the frame. | Protocol |
| PPP frame field that refers to the extra characters added to a frame for error control purposes. | frame check sequence (FCS) |
| PPP does not assign | individual station addresses. |
| Link establishment and configuration negotiation (phase 1) | An originating PPP node sends LCP frames to configure and establish the data link. |
| Link-quality determination (optional phase 2) | The link is tested to determine whether the link quality is sufficient to bring up network-layer protocols. |
| Network-layer protocol configuration negotiation (phase 3) | The originating PPP node sends NCP frames to choose and configure network-layer protocols. |
| Link termination (phase 4) | The link remains configured for communications until LCP or NCP frames close the link or until some external event occurs |
| External external event that could terminate PPP | an inactivity timer expires or a user intervenes |
| three classes of LCP frames | Link establishment frames, Link termination frames, Link maintenance frames |
| Link establishment frames | Used to establish and configure a link. |
| Link termination frames | Used to terminate a link. |
| Link maintenance frames | Used to manage and debug a link. |
| the LCP phases | : (1) Link establishment; (2) Link quality; (3) Network-layer protocol; (4) Link termination. |
| LCP frames are used to accomplish the work of | each of the LCP phases |
