C
ONFIGURING
IEEE 802.1Q T
UNNELING
12-19
Layer 2 Flow for Packets Coming into a Tunnel Port
A QinQ tunnel port may receive either tagged or untagged packets. No
matter how many tags the incoming packet has, it is treated as tagged
packet.
The ingress process does source and destination lookups. If both lookups
are successful, the ingress process writes the packet to memory. Then the
egress process transmits the packet. Packets entering a QinQ tunnel port
are processed in the following manner:
1. New SPVLAN tags are added to all incoming packets, no matter how
many tags they already have. The ingress process constructs and inserts
the outer tag (SPVLAN) into the packet based on the default VLAN
ID and Tag Protocol Identifier (TPID, that is, the ether-type of the
tag). This outer tag is used for learning and switching packets. The
priority of the inner tag is copied to the outer tag if it is a tagged or
priority tagged packet.
2. After successful source and destination lookup, the ingress process
sends the packet to the switching process with two tags. If the
incoming packet is untagged, the outer tag is an SPVLAN tag, and the
inner tag is a dummy tag (8100 0000). If the incoming packet is tagged,
the outer tag is an SPVLAN tag, and the inner tag is a CVLAN tag.
Double Tagged Packets
Outer Tag - Service Provider VID
Inner Tag - Customer VID
QinQ Tunneling
Service Provider
(edge router A)
Customer A
(VLANs 1-10)
Customer B
(VLANs 1-50)
Customer A
(VLANs 1-10)
Customer B
(VLANs 1-50)
Service Provider
(edge router B)
VLAN 10
Tunnel Port
Tunnel Port
VLAN 20
VLAN 10
Tunnel Port
Tunnel Port
VLAN 20
Summary of Contents for 7824M/FSW - annexe 1
Page 2: ......
Page 24: ...TABLE OF CONTENTS xxiv ...
Page 28: ...TABLES xxviii ...
Page 32: ...FIGURES xxxii Figure 16 3 DNS Cache 16 7 ...
Page 34: ...GETTING STARTED ...
Page 46: ...SYSTEM DEFAULTS 1 12 ...
Page 62: ...SWITCH MANAGEMENT ...
Page 74: ...CONFIGURING THE SWITCH 3 12 ...
Page 112: ...BASIC MANAGEMENT TASKS 4 38 ...
Page 168: ...USER AUTHENTICATION 6 30 ...
Page 223: ...SHOWING PORT STATISTICS 9 33 Figure 9 12 Port Statistics ...
Page 230: ...ADDRESS TABLE SETTINGS 10 6 ...
Page 304: ...CLASS OF SERVICE 13 16 ...
Page 316: ...QUALITY OF SERVICE 14 12 ...
Page 338: ...MULTICAST FILTERING 15 22 ...
Page 346: ...DOMAIN NAME SERVICE 16 8 ...
Page 348: ...COMMAND LINE INTERFACE IP Interface Commands 35 1 ...
Page 362: ...OVERVIEW OF COMMAND LINE INTERFACE 17 14 ...
Page 494: ...USER AUTHENTICATION COMMANDS 21 48 ...
Page 514: ...CLIENT SECURITY COMMANDS 22 20 ...
Page 540: ...ACCESS CONTROL LIST COMMANDS 23 26 ...
Page 558: ...INTERFACE COMMANDS 24 18 ...
Page 576: ...MIRROR PORT COMMANDS 26 4 ...
Page 582: ...RATE LIMIT COMMANDS 27 6 ...
Page 616: ...SPANNING TREE COMMANDS 29 28 ...
Page 644: ...VLAN COMMANDS 30 28 ...
Page 664: ...CLASS OF SERVICE COMMANDS 31 20 ...
Page 678: ...QUALITY OF SERVICE COMMANDS 32 14 ...
Page 720: ...APPENDICES ...
Page 726: ...SOFTWARE SPECIFICATIONS A 6 ...
Page 730: ...TROUBLESHOOTING B 4 ...
Page 746: ...INDEX Index 6 ...
Page 747: ......