ps:\u4ee5\u4e0b\u8a2d\u5b9a\u4ee52950switch\u70ba\u4e3b<\/p>\n\n\n\n
\u8a2d\u5b9atrunk \u5c01\u88dd\u65b9\u6cd5<\/strong> encapsulation dot1q \u5728trunk\u4ecb\u9762\u6307\u5b9anative vlan \u5b9a\u7fa9\u53ef\u901a\u904e\u7684vlan\u3000 …… <\/p>\n\n\n\n trunk\u8a2d\u5b9a<\/strong> DTP(Dynamic Trunk Protocol,\u601d\u79d1\u52d5\u614b\u4e2d\u7e7c\u50b3\u8f38\u5354\u5b9a)<\/strong> \u5c07port mode\u8a2d\u70batrunk \u95dc\u9589\u4ecb\u9762DTP\u904b\u4f5c \u986f\u793adtp\u904b\u4f5c\u8cc7\u8a0a ps: ……………..<\/p>\n\n\n\n \u986f\u793atrunk\u8cc7\u8a0a \u986f\u793aswitchport\u4ecb\u9762\u8cc7\u8a0a switch\u548crouter\u9593trunk\u554f\u984c\u8655\u7406\u6b65\u9a5f ………………………………………………………………………………………………………………………….<\/sub><\/p>\n\n\n\n ISL(Inter-Switch Link Protocol,\u4ea4\u63db\u5668\u9593\u93c8\u8def\u901a\u8a0a\u5354\u5b9a)<\/strong> \u904b\u4f5c\u65b9\u5f0f<\/strong> ISL frame<\/strong> DISL(\u52d5\u614b\u4ea4\u63db\u93c8\u8def\u5167\u50b3\u8f38\u5354\u5b9a)<\/strong> ps:\u4ee5\u4e0b\u8a2d\u5b9a\u4ee52950switch\u70ba\u4e3b \u8a2d\u5b9atrunk \u5c01 …<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"fifu_image_url":"","fifu_image_alt":"","_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[34],"tags":[],"class_list":["post-950","post","type-post","status-publish","format-standard","hentry","category-cisco-layer2"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/posts\/950","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/comments?post=950"}],"version-history":[{"count":0,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/posts\/950\/revisions"}],"wp:attachment":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/media?parent=950"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/categories?post=950"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/tags?post=950"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
(config)#int < interface>
(config-if)switchport trunk encapsulation < type><\/strong>
< type>\u6709ISL,dot1q,negotiate
\u3000ISL:\u7528CISCO ISL\u5c07frame\u6574\u500b\u5c01\u88dd
\u3000dot1q:\u7528802.1q\u5728frame\u4e0a\u52a0tag(\u9664\u4e86native vlan is sent normally and is not tagged)
\u3000negotiate(the default):\u81ea\u52d5\u5f9eISL\u6216dot1q\u9078\u4e00\u500b\u7528,\u82e5\u90fd\u652f\u63f4\u5247\u4f7f\u7528ISL\u3000
ps:
\u53ef\u9078type\u4f9d\u5404\u6a5f\u5668\u53ef\u80fd\u4e0d\u540c,3550switch\u6709isl,dot1q,negotiate,2912\u6709isl,dot1q,2950\u53ea\u6709dot1q,1900\u53ea\u6709isl
ps:
A Catalyst switch will report giants if one side is configured for ISL\/802.1q while the other side is not
ps:
trunk\u6642\u8981\u6ce8\u610f\u5169\u908a\u4ecb\u9762speed\/duplex\u8981\u4e00\u81f4<\/p>\n\n\n\n
(config-if)#encapsulation dot1q < vlan-id><\/strong>
Use the encapsulation dot1q subinterface command to enable IEEE 802.1Q encapsulation of traffic on a specified subinterface in virtual LANs
< vlan-id> The allowed range is 1-1000
ex:
encapsulates VLAN traffic for VLAN 100
(config)#interface fastethernet 4\/1.100
(config-if)#encapsulation dot1q 100<\/p>\n\n\n\n
(config-if)switchport trunk native vlan < vlan id><\/strong>
< vlan id>:\u6307\u5b9a\u4e0d\u52a0tag\u7684vlan,<\/strong>\u53ef\u8a2d\u7bc4\u570d\u70ba1-4096,\u9810\u8a2d\u70bavlan1,\u4ee5\u4fbftrunk\u4e0d\u8d77\u4f86\u6642\u53ef\u9023\u904e\u53bb\u7ba1\u7406
\u82e5trunk\u5931\u6557\u6642,\u8b93port\u5c6c\u65bc\u67d0vlan
\u5404switch\u4e4bnative vlan\u70ba\u4e00\u500bvlan\u7db2\u8def,\u5373\u4f7f\u6307\u5b9a\u7684native vlan id\u4e0d\u540c\u7406\u8ad6\u4e0a\u4e5f\u53ef\u5728native vlan\u4e92\u901a
ex:
switch1 trunk interface\u7684native vlan\u70ba10
\u82e5switch2 native vlan(1) untage frame\u5f9etrunk\u4ecb\u9762\u9032\u4f86
switch1\u6703\u8a8d\u70ba\u662fvlan10,\u6240\u4ee5switch2\u7684frame\u53ea\u80fd\u5728vlan 10\u6d3b\u52d5
ps:
You can bring up a trunk with different native VLANs on each end;
however, both switches will log error messages about the mismatch,and the potential exists that traffic will not pass correctly between the two native VLANs.
ex:
\u4ee5\u4e0b\u7d44\u7e54,\u53ef\u8b93\u4f7f\u7528vlan1\u8a2d\u5099\u4e4b\u6d41\u91cf\u53ef\u57282\u53f0switch\u9593\u4e92\u901a
switch 1\u4e92\u9023\u4ecb\u9762\u70ba
\u3000switchport trunk encapsulation dot1q(\u9810\u8a2d\u5141\u8a31\u4efb\u4f55vlan)
switch 2\u4e92\u9023\u4ecb\u9762\u70ba
\u3000switchport mode access
\u3000switchport trunk native vlan 1(\u6307\u5b9avlan 1\u4e0d\u52a0tag) \u3000
ps:
native VLAN mismatch is discovered through the exchange of CDP messages
ps:
\u5728ISL trunk\u4e0b,\u8a72\u6307\u4ee4\u7121\u4f5c\u7528,\u56e0\u70baISL\u4e0d\u652f\u63f4untagged VLAN<\/p>\n\n\n\n
(config-if)# switchport trunk allowed vlan < vlan-list|all|< add|except|remove> vlan-list><\/strong>
\u9810\u8a2d\u70baall,vlan-id\u53ef\u652f\u63f41-4096
\u76f8\u540c\u6307\u4ee4\u6703\u8986\u84cb
ex:
\u5047\u8a2d\u5df1allow vlan 2-4,\u5247\u4ee5\u4e0b\u5169\u8005\u7d50\u679c\u76f8\u540c
(config-if)# switchport trunk allowed vlan 2,4
(config-if)# switchport trunk allowed vlan remove 3
ps:
If one end of the trunk is configured to disallow a VLAN, that VLAN will not be contiguous across the trunk. <\/p>\n\n\n\n
\u6709\u4ee5\u4e0b2\u65b9\u5f0f
1\u624b\u52d5\u8a2d\u5b9a2\u908atrunk
2\u900f\u904eDTP\u81ea\u52d5\u5354\u55462\u908atrunk <\/p>\n\n\n\n
\u601d\u79d1\u5c08\u5c6c\u5354\u5b9a,\u7528\u65bc\u81ea\u52d5\u5354\u55462\u8a2d\u5099\u9593\u662f\u5426\u8981\u4f7f\u7528trunk
DTP frames are sent out every 30 seconds to keep neighboring switch ports informed of the link’s mode
ps:
\u5728\u7e41\u5fd9\u7684\u7db2\u8def\u4e2d\u5efa\u8b70\u95dc\u9589\u6b64DTP\u529f\u80fd,\u6539\u4ee5\u624b\u52d5\u65b9\u5f0f\u8a2d\u5b9atrunk <\/p>\n\n\n\n
(config-if)#switchport mode <\/strong>dynamic < auto|desirable>><\/strong>
< trunk>:\u5169switch\u8a2d\u5b9atrunk\u53ef\u8b93\u5169\u908a\u76f8\u540c\u7684vlan\u901a\u8a0a,\u63db\u53e5\u8a71\u8aaa\u5c31\u662f\u8b93\u6b64\u57e0\u540c\u6642\u6210\u70ba\u591a\u500bvlan\u7684\u4e00\u90e8\u4efd
ps:DTP is still operational on trunk mode,so if the far-end switch port is configured to trunk,dynamic desirable,or dynamic auto mode,trunking will be negotiated successfully.
< dynamic auto> :\u900f\u904eDTP\u914d\u5408\u5c0d\u65b9\u6539\u8b8a,\u4e0d\u4e3b\u52d5request
< dynamic desirable>:(default),\u5e0c\u671b\u6210\u70batrunk,\u9019\u6703\u9001\u51faDTP\u7684FRAME\u548c\u5c0d\u65b9\u8a2d\u5099\u505a\u5354\u8abf,\u770b\u662f\u5426\u8981\u6210\u70baTRUNK
\u5169\u4ecb\u9762\u7d93DTP\u914d\u5c0d\u7d50\u679c\u5982\u4e0b:
trunk+access\u4e0d\u6703\u6210\u70batrunk
trunk+desirable\u6703\u6210\u70batrunk
dynamic desirable+dynamic auto\u6703\u6210\u70batrunk
dynamic auto+dynamic auto\u4e0d\u4e00\u5b9a,\u72c0\u6cc1\u7121\u6cd5\u5224\u65b7
ex:
\u624b\u52d5\u5efa\u7acbtrunk
\u5728\u5169\u500b\u5df2\u9023\u7dda\u7684switch fa0\/12\u5efa\u7acbtrunk
switch1:
(config)#int fa0\/12
(config-if)#switchport mode trunk
switch2:
(config)#int fa0\/12
(config-if)#switchport mode trunk <\/p>\n\n\n\n
(config-if)#switchport nonegotiate<\/strong>
\u9810\u8a2d\u662f\u555f\u52d5
\u82e5\u95dc\u9589\u5247switchport mode dynamic\u5c07\u7121\u6cd5\u4f7f\u7528\u800c\u7121\u6cd5request
mode\u9700\u70baaccess\u6216trunk\u624d\u53ef\u4f7f\u7528<\/p>\n\n\n\n
#show dtp [interface < interface>] <\/strong><\/p>\n\n\n\n
1900switch\u7684\u8a2d\u5b9a\u65b9\u5f0f
(config-if)#trunk < act>
\u6709\u4ee5\u4e0bact\u53ef\u9078
on \u958b\u555fDISL\uff0c\u800c\u4e14\u53ef\u548c\u5176\u4ed6\u754c\u9762\u5354\u5546
off \u95dc\u9589
nonegotiate \u958b\u555fDISL,\u4f46\u4e0d\u548c\u5176\u4ed6\u754c\u9762\u5354\u5546
desirable \u82e5\u9023\u5230nonegotiate,auto,desirable\u5247\u958b\u555fDISL
auto \u82e5\u9023\u5230on,desirable\u5247\u958b\u555fDISL<\/p>\n\n\n\n
#show interface [interface] trunk<\/strong>
1
\u756b\u9762\u5927\u81f4\u5982\u4e0b:
#show interface trunk
Port Mode Encapsulation Status Native vlan
Fa0\/12 on<\/strong> 802.1q<\/strong> trunking<\/strong> 1 \/\/fa0\/12\u4ecb\u9762\u70batrunk mode,\u4f7f\u7528802.1q\u5c01\u88dd
Port Vlans allowed on trunk \/\/\u53ef\u5141\u8a31\u901a\u904e\u7684vlan
Fa0\/12 none
Port Vlans allowed and active in management domain \/\/\u76ee\u524d\u6b63\u5728\u6d3b\u52d5\u4e2d\u7684vlan
Fa0\/12 none
Port Vlans in spanning tree forwarding state and not pruned \/\/\u7d93stp\u53capruned\u5f8c,\u5be6\u969b\u53ef\u7528\u7684vlan
Fa0\/12 none
2
\u82e5\u6307\u5b9a\u4ecb\u9762,\u756b\u9762\u5927\u81f4\u5982\u4e0b
#show interface fa0\/2 trunk
Port Mode Encapsulation Status Native vlan
Fa0\/2 auto<\/strong> 802.1q not-trunking<\/strong> 1
Port Vlans allowed on trunk
Fa0\/2 1
Port Vlans allowed and active in management domain
Fa0\/2 1
Port Vlans in spanning tree forwarding state and not pruned
Fa0\/2 1
\u8aaa\u660e:\u76ee\u524dfa0\/2\u7684port mode\u70baautonegotiation,\u4f46\u6c92\u5354\u5546\u6210\u529f\u6240\u4ee5\u4e0d\u662ftrunk status<\/p>\n\n\n\n
#show interface [interface] switchport<\/strong>
ps:
show interface switchport\u70ba\u4f8b,\u756b\u9762\u5927\u81f4\u5982\u4e0b
namee: Gi4\/2
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk \/\/\u82e5\u70badown\u8868\u793a\u4ecb\u9762\u6c92\u5728\u904b\u4f5c
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default) \/\/switchport trunk native vlan 1 (default)
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk private VLANs: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL \/\/allow vlan = all
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL
[omitted]
<\/p>\n\n\n\n
ps:
1900switch\u7684\u8a2d\u5b9a\u65b9\u5f0f\u70bashow trunk
\u756b\u9762\u5927\u81f4\u5982\u4e0b:
DISL state: on, Trunking: on, Encapsulation type: ISL \/\/\u4f7f\u7528trunk\u7684\u4ecb\u9762\u7528isl\u5c01\u88dd<\/p>\n\n\n\n
……………………………………………………………………<\/p>\n\n\n\n
vlan\u4e92\u9023\u4f7f\u7528\u4e00\u689d\u7dda\u5728router\u4e0a\u7684\u8a2d\u5b9a
router(config-if)#no ip
router(config-if)#no shut
router(config-if)#int < sub-interface>
router(config-subif)#encapsulation < type> < vlan id>
router(config-subif)#ip addrress
< type>\u9700\u548c\u4f86\u6e90trunk port\u7684encapsulation type\u76f8\u540c
< vlan id>\u9700\u548c\u4f86\u6e90\u7684vlan id\u76f8\u540c
ps:\u9023\u5230router\u7684switch port\u8981\u8a2d\u6210trunk
ex:Switch\u5efavlan2,3
Vlan2\u7684gateway\u70ba192.168.2.1\/24,Vlan3\u7684gateway\u70ba192.168.3.1\/24
switch fa0\/2\u70bavlan2,fa0\/3\u70bavlan3,fa0\/12\u548cRouter fa0\/1\u9023\u7d50
Switch(config)#vlan 2
Switch(config)#vlan 3
Switch(config)#int fa0\/1
Switch(config-if)#switchport mode access
Switch(config-if)#switchport access vlan 2
Switch(config-if)#int fa0\/2
Switch(config-if)#switchport mode access
Switch(config-if)#switchport access vlan 3
Switch(config-if)#int fa0\/12
Switch(config-if)#switchport mode trunk
Switch(config-if)#switchport trunk encapsulation dot1q
Switch(config-if)#end
Router(config)#int fa0\/1
Router(config-if)#no ip address
Router(config-if)#no sh
Router(config-if)#int fa0\/1.2
Router(config-subif)#encapsulation dot1q 2
Router(config-subif)#ip address 192.168.2.1 255.255.255.0
Router(config-subif)#int fa0\/1.3
Router(config-subif)#encapsulation dot1q 3
Router(config-subif)#ip address 192.168.3.1 255.255.255.0
Router(config-subif)#end<\/sub><\/p>\n\n\n\n
1 check\u5be6\u9ad4\u5c64\u932f\u8aa4 ex:port\u662f\u5426\u6709\u9023\u63a5,fcs\u932f\u8aa4
2 check switch\u548crouter\u9593\u5169\u7aef\u96d9\u5de5\u548c\u901f\u5ea6\u8a2d\u5b9a
3 check router\u7684\u5b50\u754c\u9762 ex:\u6b63\u78ba\u7684\u5c01\u88dd\u578b\u614b,vlan id,ip address,netmask,…\u7b49
4 check ios version\u5224\u65b7\u754c\u9762\u662f\u5426\u652f\u63f4vlan turnk<\/sub><\/p>\n\n\n\n
\u601d\u79d1\u5c08\u5c6cVLAN\u50b3\u8f38\u5354\u5b9a\uff0c\u7528\u65bc\u7dad\u8b77\u4ea4\u63db\u6a5f\u548c\u8def\u7531\u5668\u9593\u7684\u901a\u4fe1\u6d41\u91cf\u7b49VLAN \u8a0a\u606f
\u4e3b\u8981\u651c\u5e36vlan(\u865b\u64ec\u7db2\u8def)\u7684\u76f8\u95dc\u8cc7\u8a0a
\u63d0\u4f9b\u4ea4\u63db\u5668\u9593\u50b3\u9001Ethernet\u8a0a\u6846\uff0cFDDI\u8a0a\u6846\uff0cToken-Ring\u8a0a\u6846\u7684\u670d\u52d9
\u8b93\u4ea4\u63db\u5668\u9593\u5728\u591a\u7a2e\u7db2\u8def\u6a21\u7d44\u4e0b\u50b3\u9001\u5404\u7a2e\u8a0a\u6846,\u652f\u63f4vlan\u7684\u670d\u52d9
ps:
IEEE\u7248\u672c\u7684vlan\u662f802.1q,\u53ef\u652f\u63f4\u591a\u5ee0\u5546
ISL Tagging\u80fd\u8207802.1Q trunk\u57f7\u884c\u76f8\u540c\u5de5\u4f5c\uff0c\u53ea\u662f\u6240\u63a1\u7528\u7684\u683c\u5f0f\u4e0d\u540c
ps:
\u4e26\u975e\u6240\u6709catalyst switch\u90fd\u6709\u652f\u63f4\u7279\u5fb5\uff1a<\/strong>
Catalyst switches\u4f7f\u7528ASIC\u57f7\u884c
\u4e0d\u5e72\u6d89\u5ba2\u6236\u7aef\u6a5f\u7ad9,\u5ba2\u6236\u7aef\u6a5f\u4e0d\u6703\u770b\u5230ISL\u50b3\u8f38\u5354\u5b9a\u982d
ISL NICs\u70ba\u4ea4\u63db\u6a5f\u8207\u4ea4\u63db\u6a5f\u3001\u8def\u7531\u5668\u8207\u4ea4\u63db\u6a5f\u3001\u4ea4\u63db\u6a5f\u8207\u4f3a\u670d\u5668\u7b49\u4e4b\u9593\u7684\u57f7\u884c\u63d0\u4f9b\u9ad8\u6548\u6548\u80fd <\/p>\n\n\n\n
\u529f\u80fd<\/strong>
ISL tag\u63a1\u7528\u4e00\u7a2eLow-Latency(\u4f4e\u5ef6\u9072)\u6a5f\u5236\u70ba\u55ae\u500b\u7269\u7406\u8def\u5f91\u4e0a\u7684\u591a VLANs \u6d41\u91cf\u63d0\u4f9b\u5fa9\u7528\u6280\u8853
ISL\u4e3b\u8981\u7528\u65bc\u5be6\u73fe\u4ea4\u63db\u6a5f\u3001\u8def\u7531\u5668\u4ee5\u53ca\u5404\u7bc0\u9ede(\u5982\u4f3a\u670d\u5668\u6240\u4f7f\u7528\u7684\u7db2\u8def\u63a5\u982d\u5361)\u4e4b\u9593\u7684\u9023\u63a5\u64cd\u4f5c
ISL\u6240\u7d44\u614b\u7684\u8def\u7531\u5668\u652f\u6301VLAN\u5167\u901a\u4fe1\u670d\u52d9,\u975eISL\u7d44\u614b\u7684\u8a2d\u5099,\u5247\u7528\u65bc\u63a5\u6536\u7531ISL\u5c01\u88dd\u7684Ethernet Frames
ps:
\u70ba\u652f\u6301 ISL \u529f\u80fd\u7279\u5fb5\uff0c\u6bcf\u53f0\u9023\u63a5\u8a2d\u5099\u90fd\u5fc5\u9808\u63a1\u7528 ISL \u7d44\u614b
<\/p>\n\n\n\n
The packet is encapsulated with a 26 byte header and a 4 byte FCS
ISL\u4f5c\u7528\u65bc OSI \u6a21\u578b\u7b2c2\u5c64
ISL\u50b3\u8f38\u5354\u5b9a\u982d\u548c\u5c3e\u5c01\u88dd\u6574\u500b\u7b2c2\u5c64\u7684Ethernet Frames
ISL\u88ab\u8a8d\u70ba\u80fd\u5728\u4ea4\u63db\u6a5f\u9593\u50b3\u9001\u7b2c2\u5c64\u4efb\u4f55\u6a94\u6848\u985e\u578b\u7684frame\u6216\u4e0a\u5c64\u50b3\u8f38\u5354\u5b9a\u7684\u7368\u7acb\u50b3\u8f38\u5354\u5b9a
ISL\u6240\u5c01\u88dd\u7684frame\u53ef\u4ee5\u662fToken Ring\u6216Fast Ethernet
ps:
\u82e5\u8a0a\u6846\u8981\u96e2\u958bvlan\u6703\u5148\u79fb\u9664\u6389ISL\u5c01\u88dd <\/strong><\/p>\n\n\n\n
30byte:\u753126-byte header\u548c4-byte trailer\u6240\u5c01\u88dd
\u683c\u5f0f\u5982\u4e0b
[DA | TYPE | USER | SA | LEN | HSA | VLAN | BPDU] payload [FCS]
DA\uff1a\u76ee\u7684\u5730\u5740\uff0c\u662f\u4e00\u500b\u7d44\u64ad\u4f4d\u5740\uff0c\u7e3d\u662f\u76f8\u540c\u768440\u4f4d01000C0000\uff0c\u544a\u8a34\u63a5\u6536\u65b9\u8a72\u6846\u8a0a\u662fISL\u683c\u5f0f\u5c01\u88dd\u7684\u3002
TYPE\uff1a\u6307\u660e\u6240\u5c01\u88dd\u798e\u7684\u985e\u578b\uff0c\u4e59\u592a\u7db20000\u3001\u6b0a\u6756\u74b0\u7db20001\u3001FDDI\u7db20010\u3001ATM 0011
USER\uff1a\u7528\u6236\u81ea\u5b9a\u7fa9
SA\uff1a\u767c\u9001\u8a72ISL\u6846\u8a0a\u7684\u4ea4\u63db\u6a5f\u4ecb\u9762\u768448\u4f4d\u5143MAC\u4f4d\u5740
LEN\uff1aISL\u6846\u8a0a\u7684\u9577\u5ea6 HSA\uff1a\u6e90\u4f4d\u5740\u9ad8\u4f4d\uff0c\u542b\u751f\u7522\u5546\u7684ID\u548cMAC\u6e90\u4f4d\u5740\u3002\u4ee500000C\u958b\u982d\u3002
VLAN\uff1a15bit,VLAN\u7684ID\u865f
BPDU\uff1a\u5982\u679c\u662fSTP\u6846\u8a0a\u5c31\u7f6e\u8a72\u4f4d\u7684\u503c
FCS\uff1aappends\u5728paylod\u4e4b\u5f8c,\u7528\u65bcCRC
ps:
frame\u589e\u52a030byte\u6703\u8d85\u904emtu(1518byte)\u800c\u7522\u751f baby giant frames<\/p>\n\n\n\n
\u7c21\u5316\u4e86\u5169\u53f0\u76f8\u4e92\u9023\u63a5\u7684\u5feb\u901f\u4e59\u592a\u7db2\u8a2d\u5099\u4e0a ISL \u5e79\u7dda\u7684\u65b0\u589e\u7a0b\u5e8f
DISL\u5be6\u73fe\u4e86\u6700\u5c0f\u5316VLAN\u5e79\u7dda,\u56e0\u70baDISL\u4e2d\u53ea\u5141\u8a31\u5c07\u4e00\u500b\u93c8\u8def\u7d42\u7aef\u7d44\u614b\u70ba\u5e79\u7dda<\/p>\n","protected":false},"excerpt":{"rendered":"