Chapter 7 Bridge Screens
ZyWALL 5/35/70 Series User’s Guide
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7.2 Spanning Tree Protocol (STP)
STP detects and breaks network loops and provides backup links between switches, bridges or
routers. It allows a bridge to interact with other STP-compliant bridges in your network to
ensure that only one route exists between any two stations on the network.
7.2.1 Rapid STP
The ZyWALL uses IEEE 802.1w RSTP (Rapid Spanning Tree Protocol) that allow faster
convergence of the spanning tree (while also being backwards compatible with STP-only
aware bridges). Using RSTP, topology change information does not have to propagate to the
root bridge and unwanted learned addresses are flushed from the filtering database. In RSTP,
the port states are Discarding, Learning, and Forwarding.
7.2.2 STP Terminology
The root bridge is the base of the spanning tree.
Path cost is the cost of transmitting a frame from the root bridge to that port. It is assigned
according to the speed of the link to which a port is attached. The slower the media, the higher
the cost - see the next table.
On each bridge, the root port is the port through which this bridge communicates with the root.
It is the port on this switch with the lowest path cost to the root (the root path cost). If there is
no root port, then this bridge has been accepted as the root bridge of the spanning tree network.
For each LAN segment, a designated bridge is selected. This bridge has the lowest cost to the
root among the bridges connected to the LAN.
7.2.3 How STP Works
After a bridge determines the lowest cost-spanning tree with STP, it enables the root port and
the ports that are the designated ports for connected LANs, and disables all other ports that
participate in STP. Network packets are therefore only forwarded between enabled ports,
eliminating any possible network loops.
STP-aware bridges exchange Bridge Protocol Data Units (BPDUs) periodically. When the
bridged LAN topology changes, a new spanning tree is constructed.
Table 30
STP Path Costs
LINK
SPEED
RECOMMENDED
VALUE
RECOMMENDED
RANGE
ALLOWED
RANGE
Path Cost
4Mbps
250
100 to 1000
1 to 65535
Path Cost
10Mbps
100
50 to 600
1 to 65535
Path Cost
16Mbps
62
40 to 400
1 to 65535
Path Cost
100Mbps
19
10 to 60
1 to 65535
Path Cost
1Gbps
4
3 to 10
1 to 65535
Path Cost
10Gbps
2
1 to 5
1 to 65535
Содержание ZyWALL 35 Series
Страница 2: ......
Страница 8: ...Safety Warnings ZyWALL 5 35 70 Series User s Guide 8 ...
Страница 52: ...List of Tables ZyWALL 5 35 70 Series User s Guide 52 ...
Страница 54: ...54 ...
Страница 60: ...Chapter 1 Getting to Know Your ZyWALL ZyWALL 5 35 70 Series User s Guide 60 ...
Страница 86: ...Chapter 2 Introducing the Web Configurator ZyWALL 5 35 70 Series User s Guide 86 ...
Страница 126: ...Chapter 4 Tutorials ZyWALL 5 35 70 Series User s Guide 126 Figure 57 SECURITY VPN VPN Rules IKE Add Network Policy ...
Страница 140: ...Chapter 4 Tutorials ZyWALL 5 35 70 Series User s Guide 140 ...
Страница 146: ...Chapter 5 Registration ZyWALL 5 35 70 Series User s Guide 146 ...
Страница 147: ...147 PART II Network LAN Screens 149 Bridge Screens 161 WAN Screens 167 DMZ Screens 203 WLAN 213 ...
Страница 148: ...148 ...
Страница 160: ...Chapter 6 LAN Screens ZyWALL 5 35 70 Series User s Guide 160 ...
Страница 173: ...Chapter 8 WAN Screens ZyWALL 5 35 70 Series User s Guide 173 Figure 93 NETWORK WAN General ...
Страница 202: ...Chapter 8 WAN Screens ZyWALL 5 35 70 Series User s Guide 202 ...
Страница 212: ...Chapter 9 DMZ Screens ZyWALL 5 35 70 Series User s Guide 212 ...
Страница 242: ...242 ...
Страница 262: ...Chapter 11 Firewall ZyWALL 5 35 70 Series User s Guide 262 Figure 146 SECURITY FIREWALL Rule Summary Edit ...
Страница 274: ...Chapter 11 Firewall ZyWALL 5 35 70 Series User s Guide 274 ...
Страница 294: ...Chapter 13 Configuring IDP ZyWALL 5 35 70 Series User s Guide 294 ...
Страница 320: ...Chapter 15 Anti Spam ZyWALL 5 35 70 Series User s Guide 320 ...
Страница 342: ...Chapter 16 Content Filtering Screens ZyWALL 5 35 70 Series User s Guide 342 ...
Страница 350: ...Chapter 17 Content Filtering Reports ZyWALL 5 35 70 Series User s Guide 350 ...
Страница 363: ...Chapter 18 IPSec VPN ZyWALL 5 35 70 Series User s Guide 363 Figure 210 SECURITY VPN VPN Rules IKE Edit Gateway Policy ...
Страница 373: ...Chapter 18 IPSec VPN ZyWALL 5 35 70 Series User s Guide 373 Figure 213 SECURITY VPN VPN Rules IKE Edit Network Policy ...
Страница 424: ...Chapter 19 Certificates ZyWALL 5 35 70 Series User s Guide 424 ...
Страница 430: ...430 ...
Страница 448: ...Chapter 21 Network Address Translation NAT ZyWALL 5 35 70 Series User s Guide 448 ...
Страница 474: ...Chapter 24 Bandwidth Management ZyWALL 5 35 70 Series User s Guide 474 ...
Страница 514: ...Chapter 26 Remote Management ZyWALL 5 35 70 Series User s Guide 514 ...
Страница 533: ...533 PART V Reports Logs and Maintenance Reports 535 Logs Screens 547 Maintenance 575 ...
Страница 534: ...534 ...
Страница 551: ...Chapter 31 Logs Screens ZyWALL 5 35 70 Series User s Guide 551 Figure 334 LOGS Log Settings ...
Страница 592: ...Chapter 32 Maintenance ZyWALL 5 35 70 Series User s Guide 592 ...
Страница 594: ...594 Troubleshooting 751 Product Specifications 757 ...
Страница 602: ...Chapter 33 Introducing the SMT ZyWALL 5 35 70 Series User s Guide 602 ...
Страница 622: ...Chapter 35 WAN and Dial Backup Setup ZyWALL 5 35 70 Series User s Guide 622 ...
Страница 628: ...Chapter 36 LAN Setup ZyWALL 5 35 70 Series User s Guide 628 ...
Страница 634: ...Chapter 37 Internet Access ZyWALL 5 35 70 Series User s Guide 634 ...
Страница 638: ...Chapter 38 DMZ Setup ZyWALL 5 35 70 Series User s Guide 638 ...
Страница 642: ...Chapter 39 Route Setup ZyWALL 5 35 70 Series User s Guide 642 ...
Страница 658: ...Chapter 41 Remote Node Setup ZyWALL 5 35 70 Series User s Guide 658 ...
Страница 662: ...Chapter 42 IP Static Route Setup ZyWALL 5 35 70 Series User s Guide 662 ...
Страница 700: ...Chapter 45 Filter Configuration ZyWALL 5 35 70 Series User s Guide 700 ...
Страница 738: ...Chapter 50 Remote Management ZyWALL 5 35 70 Series User s Guide 738 ...
Страница 746: ...Chapter 51 IP Policy Routing ZyWALL 5 35 70 Series User s Guide 746 ...
Страница 766: ...766 ...
Страница 770: ...Appendix A Hardware Installation ZyWALL 5 35 70 Series User s Guide 770 ...
Страница 778: ...Appendix B Pop up Windows JavaScripts and Java Permissions ZyWALL 5 35 70 Series User s Guide 778 ...
Страница 780: ...Appendix C Removing and Installing a Fuse ZyWALL 5 35 70 Series User s Guide 780 ...
Страница 802: ...Appendix D Setting up Your Computer s IP Address ZyWALL 5 35 70 Series User s Guide 802 ...
Страница 816: ...Appendix F Common Services ZyWALL 5 35 70 Series User s Guide 816 ...
Страница 852: ...Appendix J Importing Certificates ZyWALL 5 35 70 Series User s Guide 852 ...
Страница 856: ...Appendix K Legal Information ZyWALL 5 35 70 Series User s Guide 856 ...
Страница 862: ...Appendix L Customer Support ZyWALL 5 35 70 Series User s Guide 862 ...