Nokia M10 User’s Manual
DRAFT
E Copyright Nokia Telecommunications Oy
NTC C33539002SE_A0
6-6
6.7 Point-to-point protocol (PPP)
Point-to-point protocol is a set of network protocols which enable you
to connect TCP/IP hosts and networks over serial connections.
The nodes at each end of a PPP link are referred to as peers. Unlike
client-server networks where one device is responsible of providing
services to another, peer-to-peer network peers function as equals
providing services to one another as needed.
PPP provides a standard method of encapsulating network protocol
information over point-to-point links. PPP defines a Link Control
Protocol (LCP) which provides link configuration, peer authentication
and link quality monitoring. Finally, PPP includes several Network
Control Protocols (NCP) which specify how datagrams for a specific
higher level protocol using PPP as a datalink should be encapsulated.
Network control protocols establish and configure different network
layer protocols, such as TCP/IP.
PPP encapsulation provides transmission of different network layer
protocols simultaneously over the same link. Once a PPP link has been
established, a PPP peer can negotiate the exchange of TCP/IP, IPX or
Appletalk packets over the serial connection. Your M10 supports
transmission of both IP (RFC 1332) and Ethernet (RFC 1638) packets
over the PPP link.
The setup of a PPP link consists of the following phases:
D Link establishment
D Link configuration
D Authentication
D Network configuration
D Link up
During the link establishment the Nokia M10 synchronises its ADSL
and ATM transmission to open a physical layer connection between
Nokia M10 and the remote peer router through the ATM access
network. When the physical connection has been established the PPP
protocol can actually begin its work.
The next step is the PPP link configuration which is done using a Link
configuration Protocol (LCP). It allows optional modifications to the
standard characteristics of the PPP link to be negotiated. The
negotiable items are the maximum receive unit (MRU), link
authentication, etc.