basic ip knowledge and route technology
TRANSCRIPT
HUAWEI TECHNOLOGIES CO., LTD.
www.huawei.com
Huawei Confidential
Security Level: Internal Use Only23/5/3
Lou Sheng 52739
Basic IP Knowledge and
Route Technology
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Preface
This course is developed on the basic IP knowledge and route technology. By learning this course, you can understand the TCP/IP model and the principles at IP layer.You will know the network hierarchy model and the method of dividing subnet too.
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Guidelines
This course describes basic IP knowledge and route technology. Before learning this course, you should have basic understanding on data communications network by learning the Data Characteristics Principle.
This course focuses on TCP/IP model and principles at IP layer.
The difficulty of this course lies in the understanding of network hierarchy model and the method of dividing subnet.
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References
Data characteristics principle
Topics on data characteristics
Topic on network technology
Topic on basic principles of data
network
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Objectives
After completing this course, you should be able to: Know network hierarchy model
Describe TCP/IP basis
Describe subnet division and route technology
Know relevant network equipment
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Contents
Network Hierarchy Model The Basic TCP/IP Knowledge The Method of Dividing
Subnet and The basic Route Technology
Relevant Network Equipment
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Network Hierarchy Model
Application
Presentation
Session
Transport
Network
Datalink
Physical
OSI 7 Layer Model
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Network Communication Model
The connections between the different layers
ApplicationPresentatio
nSessionTransportNetworkData LinkPhysical
ApplicationPresentatio
nSessionTransportNetworkData LinkPhysical
NetworkData LinkPhysical
Data LinkPhysical
End System End SystemRouter Bridge
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Questions
Q1: What is the purpose of network hierarchy?
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Summary
In this chapter, you have learned:
Network Hierarchy Model
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Contents
Network Hierarchy Model The Basic TCP/IP Knowledge The Method of Dividing
Subnet and The basic Route Technology
Relevant Network Equipment
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TCP/IP Protocol and OSI Reference Model Compared with OSI, TCP/IP technology comes from
practice. TCP/IP is simple and efficient.
Application
Presentation
Session
Transport
Network
Data Link
Physical
Application
Transport
Network
Data Link
OSI Model TCP/IP
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Encapsulation Process of TCP/IP Protocol Stack
User data
User dataAppl Head
Application dataTcp Head
Ip Head
Application dataTcp Head
Eth Head Application dataTcp Head
Ip Head
Eth Head
TCP Section
IP Data Message
14 20 20 4Ethernet Frame
46-1500 Byte
Application
TCP
IP
Drive for Ethernet
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Data Encapsulation Mode of TCP/IP Protocol
TELNET23
FTP20/21
SMTP25
TFTP69
SEGMENT
IP PACKETS
FRAMES
BITS
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TCP/IP Protocol Stack
HTTP,Telnet,FTP,TFTP,Ping,etc
TCP/UDP
ARP/RARPIP IGMP ICMP
Ethernet,802.3,PPP,HDLC,FR,etc
Interface and cable
Application
Transport
Network
Data Link
Supply the NNI For application
Create the End to End Connect
addressing and route select
Physical Medium Access
Data flow by binary system Physical
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Protocols at the Application Layer
File transfer FTP and TFTP
Mail service SMTP and POP3
Network Management SNMP, Telnet, Ping and Tracert
Network Service HTTP, DNS and WINS
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Overview on Protocols at the Transmission Layer
Application
Transport
Network
TCP
UDP
Data Link
LAYERS Protocols
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Port Number
Protocols at the transmission layer use port numbers to identify various upper layer applications.
HTTP FTP Telnet SMTP DNS TFTP SNMP
TCP UDP
IP Data Package
socket 80 20/21 23 25 53 69 161
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TCP Connection
clientserver
SYN(seq=a)
SYN(seq=b,ack=a+1)
ACK(seq=b+1)
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TCP Disonnection
clientserver
FIN(seq=a)
ACK(seq=a+1)
FIN(seq=b,ack=a+1 )ACK(seq=b+1)
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Slide Window
OK,I will reduce size of slide
window
So fast! I can’t
make it
len 1024 win4096len 1024 win4096len 1024 win4096
ack 4097 win2048
len 1024 win4096len 1024 win4096
ack 6145 win2048
len 1024 win4096len 1024 win4096
len 1024 win4096
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Overview on Protocol at the Network Layer
Data Link
Application
Transport
Network
IP
ARP
RARP ICMP
LAYERS Protocols
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IP Packet Format
VersionHead length TOS Flag TTL Destination IP address Source IP address variable-length option DATA
...
priority D T R C reservation
bit0 4 8 16 19 24 31
0 1 2 3 4 5 6 7
The form of IP Packet
20 bytes fixed size
Total lengthIdentification
Protocol Packet head checksum
offset
Padding
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ARP-Address Resolution Protocol
Need the MAC address for 10.0.0.2
IP:10.0.0.1/24MAC:00-E0-FC-00-00-
11IP:10.0.0.2/24
MAC:00-E0-FC-00-00-12
ARP Request?
ARP Reply
MAC address for 10.0.0.2 :00-E0-FC-00-00-12
①
② ②
③
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RARP-Reverse Address Resolution Protocol
IP Address?
Workstation without Disk RARP Server
RARP Request?
RARP Reply
IP Address 10.0.0.1
①
② ②
③
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ICMP Protocol
Can B be accessed?
ICMP Echo Request
ICMP Echo Reply
Yes, I amA B
①
②
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Data Link Layer
Data link layer is the second layer of OSI reference model and provides
services to the network layer on the basis of the physical layer.
Data link layer provides reliable data transmission for the physical link.
The protocols at the data link layer in a LAN include Ethernet and
Token-Ring network.
The protocols at the data link layer in a WAN include PPP, HDLC, and
Frame Relay.
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Functions of Data Link Layer
•Frame synchronization •Flow Control•Link Management Data Link
Application
Transport
Network
LAYERS Function
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Frame Synchronization
Frame synchronization is a function that you can specify the start and
stop places of a data frame from the received bit stream.
General methods of frame synchronization are as follow: Byte count method
Character-Stuffing delimiter method
Bit-Stuffing delimiter method
Illegal Coding Method
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Flow Control and Link Management
Flow control is provided at the data link layer and other layers.
Flow control can control the rate of transmitting data by the transmitter.
Link management indicates connection creation, maintenance and
release at the data link layer.
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Standards at LAN Data Link Layer
IEEE 802: LAN series standards IEEE802.3: Ethernet standards
IEEE802.4: Token bus standards
IEEE802.5: Token-ring standards
IEEE802.11: Wireless LAN
IEEE 802 covers standards at the physical layer and data link layer.
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Standards at WAN Data Link Layer
WAN services are usually provided by telecom operators.
Standards at WAN Data Link Layer are as follows: HDLC
PPP
X.25
Frame Relay
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Physical Layer
Physical layer is at the lowest layer of the OSI reference model and
directly faces physical media or channel that transmits data. The
transmission unit at the physical layer is bit. Physical layer provides an
original bit stream physical connection on a physical channel for the data
link layer. Protocols at the physical layer specify mechanical, electrical,
functional and procedural features needed for creating, maintaining and
disconnecting physical channels. The physical layer ensures bit stream to
transmit on the physical channel.
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Functions at the Physical Layer
The physical layer provides channels for data equipment to transmit data. A data channel can be a physical medium or the connection of multiple physical media. A complete data transmission process includes: activating physical connection, transmitting data and terminating physical connection.
The physical layer should have the entity for data transmission to transmit data. The physical layer should: (1) ensure that data can correctly pass through the physical layer; (2) provide enough bandwidth (a bandwidth indicates the bit number passing through the channel within a second) to decrease channel blocking. The data transmission modes should meet all kinds of needs: point to point, point to multi-point, serial or concurrent, half-duplex or full duplex, and synchronization or asynchronization
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General Interfaces at the Physical Layer
10M Ethernet interface
100M Ethernet interface
1000M Ethernet interface
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10M Ethernet interface
10Base-T One of the most widely used LAN standards currently
The twisted-pair cable is used as physical transmission media.
10Base5 10Base5 was widely used in backbone LANs.
The coarse coaxial cable is used as the physical transmission media.
10Base2 The thin coaxial cable is used as the physical transmission media.
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Physical Media of 10Base-T
Category 3 twisted-pair cable
Category 4 twisted-pair cable
Category 5 twisted-pair cable
Super category 5 twisted-pair cable
Category 6 twisted-pair cable
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Wire Assignments of Category 5 Twisted-Pair Cable
Straight-through network cable
Crossover network cable
Side 1
Side 2
Side 1
12345678
12345678 1=white&orange2=orange3=white&green4=blue5=white&blue6=green7=white/brown8=brown
Side 2
Side 1 Side 2Side 1
Side 2
12345678
12345678
1=white&orange2=orange3=white&green4=blue5=white/blue6=green7=white/brown8=brown
1=white&orange2=orange3=white&green4=blue5=white&blue6=green7=white/brown8=brown
1=white&green2=green3=white&orange4=blue5=white&blue6=orange7=white/brown8=brown
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100M Ethernet interface
100Base-TX The physical medium is category 5 twisted-pair cable or higher.
The longest network segment is 100m.
100Base-FX The physical medium is single-mode fiber and the network segment can
reach 10 kilometers.
The physical medium is multi-mode fiber and the longest network
segment is 2000m.
Fast Ethernet is defined by IEEE 802.3u.
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1000M Ethernet interface 1000Base-T
The physical medium is category 5 twisted-pair cable or higher. The longest network segment is 100m.
1000Base-F The physical medium is multi-mode fiber and the longest network segment is
500m. 1000Base-SX
The physical medium is multi-mode fiber and the longest network segment is 2000m.
1000Base-LX The physical medium is single-mode fiber.
1000Base-ZX The physical medium is single-mode fiber. The length of the network segment can
be 25, 40, or 70 kilometers (extra-long).
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Questions
Q1: Describe the functions of all layers in TCP/IP protocol stack. Q2: Describe two kinds of technologies at the transmission layer. Q3: which layer of the TCP/IP protocol stack does the IP protocol work
in?
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Summary
In this chapter, you have learned:
The functions of each layers in TCP/IP
protocol stack.
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Contents
Network Hierarchy Model The Basic TCP/IP Knowledge The Method of Dividing
Subnet and The basic Route Technology
Relevant Network Equipment
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Basis of Subnet PlanningPurpose of subnet planning
MAN and WAM cannot adopt the broadcast technology, so rational routing is mandatory.The irregularity and fixedness of the MAC addresses bring difficulty in WAN routing.The logic address (IP address) is flexible and can be planned.Subnet division can decrease the address number and ease route pressure.
Methods of Subnet DivisionThe scheme on the IP address divided IP addresses into subnet address and NE address. The mask is used to differentiate two kinds of addresses.Based on the preceding method, the global networks can be divided regularly into flexible and adjustable subnets. In addition, rational routing can be performed.Network management can benefit from further division of subnets.
Example:Telephone number of PSTN: Country code + area code + local telephone number. PSTN is also a kind of subnet division.
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Introduction to IP Address
An IP address is a unique label of a network computer.
Private IP address 10.0.0.0-10.255.255.255 172.16.0.0-172.31.255.255 192.168.0.0-192.168.255.255
10.110.192.111 20.130.188.144
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0
1 0
1 1 0
1 1 1 0
1 1 1 1 0
Network(7bit)
Network(14bit)
Network(21bit)
× é ² ¥ µØÖ·
± £ Áô
Host (24bit)
Host(16bit)
Host(8bit)
AÀà µØÖ·
BÀà µØÖ·
CÀà µ ØÖ·
DÀà µ ØÖ·
EÀà µØÖ·
128.0.0.0~191.255.255.255
192.0.0.0~223.255.255.255
224.0.0.0~239.255.255.255
240.0.0.0~255.255.255.255
Classification of IP Address
1.0.0.0~126.255.255.255Class A
Class B
Class C
Class D
Class E
Multicast
reservation
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Special IP Addressnetworks Host Address type purpose
127 any
all“0”
all“1”
Any
all“0”Any
all“1”
subnet address Indicate a network identifier
Broadcast address Indicate all hosts in a network
Loopback address
Loopback test
All hosts
Unknown network The default route in router
Broadcast address
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Introduction to Subnet Mask
The network equipment uses the subnet mask to determine which part of
the IP address belongs to the network part and which part belongs to the
NE part.
The format of a subnet mask is the same as that of an IP address. The
network part and subnet part of a subnet mask are 1 and NE part is 0. If
subnet division is not performed, the subnet mask of class A network is
255.0.0.0, that of class B network is 255.255.0.0, and that of class C network
is 255.255.255.0 by default. The subnet can make the network address more
effective. A network is divided into different subnets internally, but is a
complete network externally.
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Networks Address and Subnet Mask
IP address :
192 . 168 . 1. 100
subnetMask :
subnet address :192 . 168 . 1. 0
255.255.255. 0
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IP address:
subnet mask:
Bit sum of Mask :
Expression of IP Address:
255 . 255 . 255 . 240255 . 255 . 255 . 24011111111 11111111 11111111 11110000
192 . 168 . 1 . 7192 . 168 . 1 . 711000000 10101000 00000001 00000111
8 + 8 + 8+ 4 = 28
192.168.1.7/28192.168.1.7/28
Subnet Address and Subnet Mask
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IP address
Subnet mask
subnet address(binary )
192.168.1.16/28192.168.1.16/28
255 . 255 . 255 . 240255 . 255 . 255 . 24011111111 11111111 11111111 11110000
192 . 168 . 1 . 23192 . 168 . 1 . 2311000000 10101000 00000001 00010111
11000000 10101000 00000001 00010000
IP address is : 192.168.1.23/28
Calculation of Subnet Address
subnet address(decimal )
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Host sum : 2n
Usable host sum : 2n - 2
Subnet mask
n
subnet bitmapsubnet bitmap Host bitmap
11 1 111 1 111 1 111 000 0 000000 000 0
Calculation of Host Number
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IP address : 192.168.1.100/28 /28 = 255.255.255.240
The binary code of the subnet mask is:11111111 , 11111111 , 11111111 , 11110000
28bits subnet
bitmap
4bitsHost bitmap
The subnet sum : 28-4
The usable subnet sum : 28-4-2
Example:Calculation of Subnet Address
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Ip address : 192.168.1.100/28 /28=255.255.255.240
28bitsnetwork
bitmap
4bitsHost
bitmapThe host sum : 24
The usalbe host sum: 24 -2
Example:Calculation of Host Count
The binary code of the subnet mask is:11111111 , 11111111 , 11111111 , 11110000
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Cases of Subnet Planning For example, a company is assigned with the class-C address
201.222.5.0. If 20 subnets are needed and each subnet is accessed with
five computers, how can the subnet be divided?
201.222.5.0
255.255.255.0201.222.5.8
255.255.255.248
201.222.5.16255.255.255.248
201.222.5.24
255.255.255.248
201.222.5.32
255.255.255.248
201.222.5.9255.255.255.248
201.222.5.17255.255.255.248
201.222.5.25255.255.255.248
201.222.5.33255.255.255.248
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Variable Length Subnet Mask (VLSM)
192.168.1.32/27
192.168.1.64/27
192.168.1.96/27
192.168.1.128/27
192.168.1.160/30
192.168.1.164/30192.168.1.168/30
192.168.1.172/30
ISP notice192.168.1.0
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Classless Inter-Domain Routing (CIDR)
CIDR reduces the scale of the route table and adds the network
expandability.
Internet
198.168.1.0
198.168.2.0
198.168.3.0
ISP
route198.168.0.0/16
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What is a route?
A route is a path message that guides the IP packet forwarding.
R1Destination
network
Other network
Interface M
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Classification of Route
Static route manually configured (static route). Static route has no overhead and can be simply configured. However, manual
maintenance is needed. The static route is adaptable for simply topology networks.
Route discovered by dynamic route protocol (dynamic route) Dynamic route has big overheads and the configuration is complex. However,
manual maintenance is unneeded. The dynamic route is adaptable for complex topology networks.
Default route The default route has no overhead and can be simply configured. However, manual
maintenance is needed. The default route can be manually configured or generated by the route protocol.
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Which are the necessary element in a route table?
Displaying Route Table Information
[Quidway]display ip routingRouting Tables:Destination/Mask proto pref Metric Nexthop Interface 0.0.0.0/0 Static 60 0 120.0.0.2 Serial0 8.0.0.0/8 RIP 100 3 120.0.0.2 Serial0 9.0.0.0/8 OSPF 10 50 20.0.0.2 Ethernet0 9.1.0.0/1 RIP 100 4 120.0.0.2 Serial0 11.0.0.0/8 Static 60 0 120.0.0.2 Serial0 20.0.0.0/8 Direct 0 0 20.0.0.1 Ethernet0 20.0.0.1/32 Direct 0 0 127.0.0.1 LoopBack0 ......
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Basic Principle of Dynamic Route Protocol
Functions of dynamic route protocol Route calculation and discovery
Obtain the route from the router to other network segment in the
network by certain means.
How can the dynamic route protocol make it? Each router sends the known route-related information to the adjacent
router. Finally, all routers can receive all routing information in the
network. Then the ultimate route can be calculated by using certain
algorithm (the next hop and cost are needed to be calculated).
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Position of Dynamic Route Protocol in Protocol Stack
BGP
TCP
Network layer ( IP ) DataLink Layer
Physical Layer
UDP
RIP
EIGRPIGRP IS-ISOSPFTransport Layer
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Classification of Dynamic Route Protocol
According to the running scope of the protocol IGP (EIGRP proprietary by RIP and Cisco, IGRP, OSPF as well as IS-IS)
EGP (BGP)
According to the routing algorithm of the route protocol Distance vector (RIP, IGRP, EIGRP, and BGP)
Link status (OSPF and IS-IS)
According to the data stream Unicast route protocol
Multicast route protocol (DVMRP, PIM-SM, and PIM-DM)
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Questions
Q1: Among class A, class B and class C addresses, which network segment belongs to private addresses?
Q2: Which network segment does this IP address belong to: 202.96.128.235/28?
Q3: If there are multiple routes to the same destination network, how can the equipment choose the best route?
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Summary
In this chapter, you have learned:
The structure of IP address The Method of Dividing Subnet The basic Route Technology
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Contents
Network Hierarchy Model The Basic TCP/IP Knowledge The Method of Dividing
Subnet and The basic Route Technology
Relevant Network Equipment
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Classification of Common Network Equipment
According to the network layers where the network equipment functions are implemented
Equipment at the physical layer Equipment at the data link layer Equipment at the network layer
According to the network positions of the network equipment Access layer equipment Convergence layer equipment Core layer equipment
Following describe the network equipment according to the network layers where the network equipment functions are implemented.
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Equipment at the Physical Layer (Hub/Repeater)
Working at the physical layer, providing signal regeneration and repeat functions, expanding network distance and network topology
Repeater Original and currently rare network equipment, providing signal
regeneration and repeat and expanding network distance
HUB Working at the physical layer, like a multi-port repeater, regenerating
and retiming bit signals, similar to a high speed bus When a port receives data, the port forwards the data to all ports. A HUB is a star structure physically and a bus structure logically.
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Equipment at the Data Link Layer (L2) Works at the physical layer and data link layer
Introduces the routing technology, so communication no longer relies on broadcast technology only.
Solves the collision domain problem and effectively isolates the network segments.
Supports full duplex mode. Supports other new technologies, such as VLAN, STP
and flow control. Suppresses the broadcast packets. Supports interconnection between heterogeneous
networks. The inside of L2 switch consists of XC matrix and
multiple concurrent data buses exist. Frame exchange is implemented by ASIC. Line speed forwarding can be implemented with low cost.
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Equipment at the Network Layer (Router) Works at the network layer (IP and IPX), and
implements routing and data forwarding. Maintains L3 protocol based route table. Forwards data based on route table. Supports multiple ports and protocols. Interconnects between VLANs. Interconnects between heterogeneous networks. Features the function of a gateway and implements
isolation between NAT and subnet. Ensures network security and enables access control
to some extent (firewall). The difference between the router and switch lies in
routing. The routing of a router adopts CPU and software algorithm, so the efficiency is lower, compared with hardware.
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L3 Switch (L3) A network needs both L2 and L3 switches. Traditionally, the
network consists of routers and L2 switches. As a result, a large number of equipment exists, which increases the cost and reduces the efficiency.
Solution: Integrate the functions of the router and L2 switch: L3 switch can feature L2 switching and L3 routing functions.
L3 is based on hardware ASIC, so has higher efficiency that the router.
Optimize Ethernet specially. Preliminary BAS function is implemented. Some new features are introduced, such as ARP agency and
VLAN convergence (L2 switch and the router do not feature these functions).
Catalyst 6500
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Router Vs L3 Switch
Topic Router L3Port type Multiform,
including :Erthernet/POS/ATM
Simple,including erthernet only
Port number Less MoreRoute rule The longest prefix
matching All prefix matching
Forward efficiency
Low Hight
cost Hight lowL2 switch No support support
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Questions
Q1: Describe network equipment according to network layers? Q2: What are the main differences between a HUB and a L2 switch? Q3: Can L3 switch replace the router?
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Summary
In this chapter, you have learned:
Relevant Network Equipment
The function of each Network Equipment
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This course describes:This course describes: Network Hierarchy Model Network Hierarchy Model The Basic TCP/IP Knowledge The Basic TCP/IP Knowledge The Method of Dividing Subnet The Method of Dividing Subnet
and The basic Route Technologyand The basic Route Technology Relevant Network EquipmentRelevant Network Equipment
Sum-up
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