Chapter 11: Classifiers
130
Section II: Advanced Operations
Figure 5. User Priority and VLAN Fields within an Ethernet Frame
You can identify a traffic flow of tagged packets using the user priority
value. A classifier for such a traffic flow would instruct a port to watch for
tagged packets containing the specified user priority level.
The priority level criteria can contain only one value, and the value must
be from 0 (zero) to 7. Multiple classifiers are required if a port is to watch
for several different traffic flows of different priority levels.
VLAN ID (Layer 2)
A tagged Ethernet frame also contains within it a field of 12 bits that
specifies the ID number of the VLAN to which the frame belongs. The
field, illustrated in Figure 5, can be used to identify a traffic flow.
A classifier can contain only one VLAN ID. To create a port ACL or QoS
policy that applies to several different VLAN IDs, multiple classifiers are
required.
Protocol (Layer 2)
Traffic flows can be identified by the protocol specified in the Ethertype
field of the MAC header in an Ethernet II frame. Possible values are:
IP
ARP
RARP
Protocol Number
Preamble
Destination
Address
Source
Address
Type/
Length
Frame Data
CRC
64 bits
48 bits
48 bits
16
bits
368 to 12000 bits
32 bits
Tag Protocol Identifier
User
Priority CFI
VLAN Identifier
16 bits
3 bits
1
bit
12 bits
Содержание AT-S63
Страница 14: ...Figures 14 ...
Страница 18: ...Tables 18 ...
Страница 28: ...28 Section I Basic Operations ...
Страница 58: ...Chapter 1 Overview 58 ...
Страница 76: ...Chapter 2 AT 9400Ts Stacks 76 Section I Basic Operations ...
Страница 96: ...Chapter 5 MAC Address Table 96 Section I Basic Operations ...
Страница 114: ...Chapter 8 Port Mirror 114 Section I Basic Operations ...
Страница 116: ...116 Section II Advanced Operations ...
Страница 146: ...Chapter 12 Access Control Lists 146 Section II Advanced Operations ...
Страница 176: ...Chapter 14 Quality of Service 176 Section II Advanced Operations ...
Страница 196: ...196 Section III Snooping Protocols ...
Страница 204: ...Chapter 18 Multicast Listener Discovery Snooping 204 Section III Snooping Protocols ...
Страница 216: ...Chapter 20 Ethernet Protection Switching Ring Snooping 216 Section III Snooping Protocols ...
Страница 218: ...218 Section IV SNMPv3 ...
Страница 234: ...234 Section V Spanning Tree Protocols ...
Страница 268: ...268 Section VI Virtual LANs ...
Страница 306: ...Chapter 27 Protected Ports VLANs 306 Section VI Virtual LANs ...
Страница 320: ...320 Section VII Internet Protocol Routing ...
Страница 360: ...Chapter 30 BOOTP Relay Agent 360 Section VII Routing ...
Страница 370: ...Chapter 31 Virtual Router Redundancy Protocol 370 Section VII Routing ...
Страница 372: ...372 Section VIII Port Security ...
Страница 402: ...Chapter 33 802 1x Port based Network Access Control 402 Section VIII Port Security ...
Страница 404: ...404 Section IX Management Security ...
Страница 436: ...Chapter 36 PKI Certificates and SSL 436 Section IX Management Security ...
Страница 454: ...Chapter 38 TACACS and RADIUS Protocols 454 Section IX Management Security ...
Страница 462: ...Chapter 39 Management Access Control List 462 Section IX Management Security ...
Страница 504: ...Appendix B SNMPv3 Configuration Examples 504 Security Model Security Level Storage Type SNMPv3 Parameters Continued ...
Страница 532: ...Appendix D MIB Objects 532 ...