Firewall Overview
553
Table 620
Mnemonic Symbol of the ICMP Message Type
By configuring the firewall and adding appropriate access rules, you can use
packet filtering to check IP packets that pass the router. The passing of unexpected
packets can thus be prohibited. In this way the packet filtering helps to protect the
network security.
Configure the match sequence of access control list
An access control rule can be composed of several “
permit
”
and “
deny
”
statements and the range of the data packet specified by each statement varies.
The match sequence needs to be configured when matching a data packet and
access control rule.
The maximum number of rules configured under an
acl-number
is 500 (that is,
500 rules can be configured in normal time range, and 500 rules can also be
configured in special time range), and the number of total rules under all
acl-number
are not more than 500. When there is a conflict among several rules,
the system will configure the match rules according to the following principle:
■
Rules with the same serial number can be defined. If two rules with the same
serial number conflict, use the “depth-first” principle to judge the
source
-
addr,
source-wildcard-mask, destination-addr, destination-wildcard-mask,
protocol
number and port number, then determine the sequence of the rule.
■
If the ranges defined by the rules are the same, then determine the sequence
of the rules according to the time sequence of definition. The system will
choose the rule defined earlier.
Operator and Syntax
Meaning
echo
echo-reply
fragmentneed-DFset
host-redirect
host-tos-redirect
host-unreachable
information-reply
information-request
net-redirect
net-tos-redirect
net-unreachable
parameter-problem
port-unreachable
protocol-unreachable
reassembly-timeout
source-quench
source-route-failed
timestamp-reply
timestamp-request
ttl-exceeded
Type=8, Code=0
Type=0, Code=0
Type=3, Code=4
Type=5, Code=1
Type=5, Code=3
Type=3, Code=1
Type=16,Code=0
Type=15,Code=0
Type=5, Code=0
Type=5, Code=2
Type=3, Code=0
Type=12,Code=0
Type=3, Code=3
Type=3, Code=2
Type=11,Code=1
Type=4, Code=0
Type=3, Code=5
Type=14,Code=0
Type=13,Code=0
Type=11,Code=0
Содержание 3036
Страница 1: ...http www 3com com 3Com Router Configuration Guide Published March 2004 Part No 10014299 ...
Страница 4: ...VPN 615 RELIABILITY 665 QOS 681 DIAL UP 721 ...
Страница 6: ...2 ABOUT THIS GUIDE ...
Страница 7: ...I GETTING STARTED Chapter 1 3Com Router Introduction Chapter 2 3Com Router User Interface ...
Страница 8: ...4 ...
Страница 16: ...12 CHAPTER 1 3COM ROUTER INTRODUCTION ...
Страница 34: ...30 ...
Страница 60: ...56 CHAPTER 3 SYSTEM MANAGEMENT ...
Страница 88: ...84 CHAPTER 5 CONFIGURING NETWORK MANAGEMENT RouterA interface ethernet 0 RouterA Ethernet0 rmon promiscuous ...
Страница 98: ...94 CHAPTER 6 DISPLAY AND DEBUGGING TOOLS ...
Страница 110: ...106 ...
Страница 114: ...110 CHAPTER 8 INTERFACE CONFIGURATION OVERVIEW ...
Страница 158: ...154 CHAPTER 10 CONFIGURING WAN INTERFACE ...
Страница 168: ...164 ...
Страница 188: ...184 CHAPTER 13 CONFIGURING PPPOE CLIENT ...
Страница 192: ...188 CHAPTER 14 CONFIGURING SLIP Router ip route static 0 0 0 0 0 0 0 0 10 110 0 1 ...
Страница 248: ...244 CHAPTER 16 CONFIGURING LAPB AND X 25 ...
Страница 292: ...288 CHAPTER 18 CONFIGURING HDLC Enable HDLC packet debugging debugging hdlc packet interface type number ...
Страница 320: ...316 ...
Страница 330: ...326 CHAPTER 20 CONFIGURING IP ADDRESS ...
Страница 362: ...358 CHAPTER 21 CONFIGURING IP APPLICATION ...
Страница 374: ...370 CHAPTER 23 CONFIGURING IP COUNT ...
Страница 406: ...402 CHAPTER 25 CONFIGURING DLSW ...
Страница 408: ...404 ...
Страница 452: ...448 CHAPTER 29 CONFIGURING OSPF ...
Страница 482: ...478 CHAPTER 30 CONFIGURING BGP ...
Страница 494: ...490 CHAPTER 31 CONFIGURING IP ROUTING POLICY ...
Страница 502: ...498 ...
Страница 508: ...504 CHAPTER 33 IP MULTICAST ...
Страница 514: ...510 CHAPTER 34 CONFIGURING IGMP ...
Страница 526: ...522 CHAPTER 36 CONFIGURING PIM SM ...
Страница 528: ...524 ...
Страница 532: ...528 CHAPTER 37 CONFIGURING TERMINAL ACCESS SECURITY ...
Страница 550: ...546 CHAPTER 38 CONFIGURING AAA AND RADIUS PROTOCOL ...
Страница 590: ...586 CHAPTER 40 CONFIGURING IPSEC ...
Страница 599: ...IX VPN Chapter 42 Configuring VPN Chapter 43 Configuring L2TP Chapter 44 Configuring GRE ...
Страница 600: ...596 ...
Страница 638: ...634 CHAPTER 43 CONFIGURING L2TP ...
Страница 649: ...X RELIABILITY Chapter 45 Configuring a Standby Center Chapter 46 Configuring VRRP ...
Страница 650: ...646 ...
Страница 666: ...662 ...
Страница 670: ...666 CHAPTER 47 QOS OVERVIEW ...
Страница 700: ...696 CHAPTER 49 CONGESTION MANAGEMENT ...
Страница 706: ...702 CHAPTER 50 CONGESTION AVOIDANCE ...
Страница 707: ...XII DIAL UP Chapter 51 Configuring DCC Chapter 52 Configuring Modem ...
Страница 708: ...704 ...
Страница 762: ...758 CHAPTER 52 CONFIGURING MODEM ...