1 chapter overview ip ipx netbeui appletalk. 2 network layer protocols responsible for end-to-end...
TRANSCRIPT
1
Chapter Overview
IP IPX NetBEUI AppleTalk
2
Network Layer Protocols
Responsible for end-to-end communications on an internetwork
Contrast with data-link layer protocols, which provide communications on the same local area network (LAN)
3
IP Encapsulation
4
IP Functions
Encapsulation Addressing Routing Fragmentation Protocol identification
5
The IP Datagram Format
6
IP Addresses Internet Protocol (IP) is the only network layer
protocol with its own addressing system. IP addresses are 32 bits long. IP addresses have two parts: a network identifier
and a host identifier. IP addresses are assigned to network interface
adapters, not to computers. The Source IP Address field in the IP header
always identifies the computer that generated the packet.
The Destination IP Address field in the IP header always identifies the packet’s final destination.
7
End Systems and Intermediate Systems
8
Fragmentation Routers connect networks that support different-
sized packets. The largest packet size supported by a network is
called its maximum transmission unit (MTU). When a packet is too large to be forwarded to a
particular network, the router splits it into fragments.
Each fragment is encapsulated with a header and is transmitted as a separate packet.
Fragments are not reassembled until they reach their final destination.
Fragments can themselves be fragmented.
9
Fragmentation (Cont.)
10
Protocol Field Values
0 IP
1 ICMP
3 Gateway-to-Gateway Protocol (GGP)
6 TCP
8 Exterior Gateway Protocol (EGP)
17 UDP
11
The IPX Standard
Developed by Novell for use with NetWare
Proprietary; never published as a public standard
Reverse engineered by Microsoft to create NWLink
12
IPX Functions
Routing Addressing Protocol identification
13
The IPX Header Format
14
IPX Addressing
Internet Packet Exchange (IPX) uses Separate node and network addresses Network interface adapter hardware
addresses for node addresses Network addresses
Are assigned by administrators Do not need to be registered
15
NetBEUI Characteristics
Original Microsoft Windows default networking protocol
Designed for small local area networks (LANs)
Does not support Internet communications Does not need configuration Can be used to troubleshoot Transmission
Control Protocol/Internet Protocol (TCP/IP) configuration protocols
16
NetBIOS Names
Assigned to computers during Windows installation
Sixteen characters long; the sixteenth character is a resource identifier
Can identify computers, domain controllers, users, groups, and other resources
Have no network identifier (which is why NetBEUI is nonroutable)
17
The NBF Protocol Format
18
Protocols Using NBF
Name Management Protocol (NMP) Session Management Protocol (SMP) User Datagram Protocol (UDP) Diagnostic and Monitoring Protocol
(DMP)
19
AppleTalk Data-Link Layer Options
LocalTalk EtherTalk Fast EtherTalk TokenTalk FDDITalk
20
Datagram Delivery Protocol
AppleTalk’s network layer protocol Provides packet addressing, routing,
and protocol identification Has short-format and long-format
packet headers
21
AppleTalk Addressing AppleTalk computers have a unique 8-bit
node ID that is self-assigned. AppleTalk networks can have no more
than 254 nodes. AppleTalk uses 16-bit network numbers
for routing. Computers obtain network numbers using
the Zone Information Protocol (ZIP). Computer processes are identified by 8-
bit socket numbers.
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AppleTalk Addressing (Cont.)
Network numbers, node IDs, and socket numbers are expressed as three decimal numbers, separated by periods.
AppleTalk computers resolve node IDs into hardware addresses, using the AppleTalk Address Resolution Protocol (AARP).
AppleTalk computers also have friendly names and groups of computers called zones.
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Chapter Summary Network layer protocols are responsible for end-
to-end communications across the network. IP is a connectionless protocol that encapsulates
transport layer data into datagrams. IPX is a proprietary standard that performs
routing, addressing, and protocol identification. NetBIOS Extended User Interface (NetBEUI) is
used by small Windows networks for LAN networking.
AppleTalk provides basic networking to small networks.