Zyxel XGS-4728F [148/491] How stp works

Zyxel XGS-4728F [148/491] How stp works
Chapter 13 Spanning Tree Protocol
XGS-4526/4528F/4728F User’s Guide
148
Path cost is the cost of transmitting a frame onto a LAN through that port. The
recommended cost is assigned according to the speed of the link to which a port is
attached. The slower the media, the higher the cost.
On each bridge, the bridge communicates with the root through the root port. The
root port 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 Switch 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.
13.1.2 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 switches exchange Bridge Protocol Data Units (BPDUs) periodically.
When the bridged LAN topology changes, a new spanning tree is constructed.
Once a stable network topology has been established, all bridges listen for Hello
BPDUs (Bridge Protocol Data Units) transmitted from the root bridge. If a bridge
does not get a Hello BPDU after a predefined interval (Max Age), the bridge
assumes that the link to the root bridge is down. This bridge then initiates
negotiations with other bridges to reconfigure the network to re-establish a valid
network topology.
Table 26 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

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Здравствуйте! Свич Zyxel XGS-4728F в консоле видает : Bootbase Version: V1.00 | 10/22/2007 12:48:50RAM:Size = 128 MbytesDRAM POST: Testing:131072K OKDRAM Test SUCCESS !FLASH: Intel 64MCopyright (c) 1994 - 2011 ZyXEL Communications Corp.Data abort occuredFault Status = 0x000000F5Fault Addr = 0xE59FF570Current Task TCB = 0x0129ED10Current Task Name = PINICurrent Task Stack Start = 0x0129EDACCurrent Task Stack End = 0x012A5E2BAbnormal Stack Task List : NONE r0= 0x000000F5 r1= 0xE59FF570 r2= 0xE59FF018 r3= 0xE59FF000 r4= 0x00D135FC r5= 0xE59FF018 r6= 0x00D135FC r7= 0x00067FC0 r8= 0x00D135FC r9= 0x00000000 r10=0x00000004 fp= 0x012A5CD4 r12=0x00000000 sp= 0x012A5C14 lr= 0x00000564 pc= 0x0011DC40 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 12a5cc8: 01 2a 5d 08 01 2a 5c d8 00 11 e8 6c 00 11 d9 d8 .*]..*\.l. 12a5cd8: 00 00 00 00 00 00 00 00 01 1b 13 74 01 2a 5d 08 .t.*]. 12a5ce8: 00 d1 44 f8 00 cf a2 10 00 cf a3 38 00 00 00 00 ..D.8. 12a5cf8: 00 00 00 00 01 2a 5d 7c 01 2a 5d 0c 00 12 06 80 .*]|.*]. 12a5d08: 00 11 e7 90 00 08 c6 d4 00 65 7d 34 00 fe 12 b0 .e}4. 12a5d18: 01 2a 5d 34 01 2a 5d 28 00 09 b8 c4 00 08 c6 c8 .*]4.*]. 12a5d28: 01 2a 5d 4c 01 2a 5d 38 00 17 c9 3c 00 09 b8 c0 .*]L.*]8.<. 12a5d38: 00 fe 12 b0 00 00 00 00 01 2a 5d 64 01 2a 5d 50 .*]d.*]P 12a5d48: 00 17 c9 b8 00 09 bb e8 00 ae c1 58 00 ae c2 28 .X( 12a5d58: 01 2a 5d 7c 01 2a 5d 68 01 2a 5d 7c 00 d0 7b 44 .*]|.*]h.*]|..{D 12a5d68: 00 d0 7b 44 00 cf a2 10 01 2a 5e 10 01 2a 5d 80 ..{D.*^..*]. 12a5d78: 00 06 ff b8 00 12 06 5c 00 00 01 2c 23 f1 97 40 .\.,#..@ 12a5d88: 00 0e 68 c0 00 00 00 00 ef ef ef ef ef ef ef ef ..h. 12a5d98: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a5da8: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a5db8: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a5dc8: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a5dd8: ef ef ef ef ef ef ef ef 00 00 00 01 00 00 00 53 .S 12a5de8: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 . 12a5df8: 00 00 00 00 00 00 00 00 00 00 00 00 01 2a 5e 20 .*^ 12a5e08: 01 2a 5e 14 00 65 80 4c 00 06 fd d4 00 00 00 00 .*^..e.L. 12a5e18: 01 2a 5e 24 00 00 00 00 00 65 80 2c 00 00 00 00 .*^$.e.,. 12a5e28: ef ef ef ef 00 00 00 00 00 00 00 00 00 00 00 00 . 12a5e38: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 . 12a5e48: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 . 12a5e58: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 . 12a5e68: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 . 12a5e78: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 . 12a5e88: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 . 12a5e98: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 . 12a5ea8: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 . 12a5eb8: 00 00 00 00 00 00 00 00 00 00 00 00 54 48 52 44 .THRD 12a5ec8: 00 00 00 01 01 2a 7e a0 01 2a 5f 60 01 2a 7f 5f .*~..*_`.*._ 12a5ed8: 00 00 20 00 00 00 00 00 00 00 00 00 01 2a 5e c4 .. .*^. 12a5ee8: 01 2a 5e c4 00 93 0c 50 00 00 00 04 00 00 00 03 .*^.P. 12a5ef8: 00 00 00 00 00 00 00 00 00 00 00 04 00 00 00 10 . 12a5f08: 00 00 00 00 00 08 d4 4c 01 2a 5e c4 00 00 00 00 .L.*^. 12a5f18: 00 00 00 00 00 65 89 30 01 2a 5e c4 00 00 00 00 .e.0.*^. 12a5f28: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 . 12a5f38: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 . 12a5f48: 00 00 00 00 00 00 00 00 00 00 00 00 01 2a 7f f8 .*.. 12a5f58: 01 29 ed 10 00 00 00 00 ef ef ef ef ef ef ef ef . 12a5f68: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a5f78: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a5f88: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a5f98: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a5fa8: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a5fb8: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a5fc8: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a5fd8: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a5fe8: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a5ff8: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a6008: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a6018: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a6028: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a6038: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a6048: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a6058: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a6068: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a6078: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a6088: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a6098: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a60a8: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a60b8: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef . 12a60c8: ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef .Bootbase Version: V1.00 | 10/22/2007 12:48:50RAM:Size = 128 MbytesFLASH: Intel 64M Как устранить проблему? Спасибо.
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