networking strategies

1. Data Link Protocols
 Often called layer 2 protocols.
 Data link protocols exist in the protocol
layer just above the physical layer relative
to the OSI protocol model.
 Data link protocols provide communication
between two devices.
 Because there are many different ways to
connect devices, there are many different
data link protocols.
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2. SLIP (Serial Line Interface
Protocol)
 SLIP is a data link control facility for
transmitting IP packets, usually between an
ISP (Internet service provider) and a home
user over a dial-up link.
 SLIP has some limitations, including a lack
of any error-detection and correction
mechanisms.
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3. PPP (Point to Point Protocol)
 The PPP (Point-to-Point Protocol) that
people use to connect to the Internet via a
dial-up modem is an example of a data link
protocol.
 Because the link between two systems is
point to point, the bits are always delivered
from sender to receiver in order.
 Also, unlike shared-media LANs in which
multiple stations attempt to use the
network, there is no contention
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4. SDLC (Synchronous Data Link
Protocol)
 This protocol was originally developed by
IBM as part of IBM's SNA (Systems
Network Architecture).
 It was used to connect remote devices to
mainframe computers at central locations
in either point-to-point (one-to-one) or
point-to-multipoint (one-to-many)
connections.
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5. HDLC (High-level Data Link
Control) Protocol
 HDLC (High-level Data Link Control) is a
data link layer protocol used for
transmitting data between network points
(sometimes called nodes).
 In HDLC, data is organized into a unit
(called a frame) and sent across a network
to a destination that verifies its successful
arrival.
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6. HDLC (High-level Data Link
Control) Protocol
 The HDLC protocol also manages the flow
or pacing at which data is sent.
 HDLC is one of the most commonly-used
protocols in what is layer 2 of the industry
communication reference model called
Open Systems Interconnection (OSI).
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