Chapter 3 Vlan Mapping Configuration; Vlan Mapping Overview; Introduction To Vlan Mapping; Vlan Mapping Implementation - H3C S3100 Series Operation Manual

Operation Manual (For Soliton) – VLAN-VPN
H3C S3100 Series Ethernet Switches

Chapter 3 VLAN Mapping Configuration

3.1 VLAN Mapping Overview

3.1.1 Introduction to VLAN Mapping

The VLAN mapping function can replace the private network VLAN tag of a customer
packet with a public network VLAN tag, so that the customer packet can be transmitted
within the public network in a way conforming to the public network layout. When the
packet reaches the peer customer network, the VLAN tag of the packet is restored to
the previous private network VLAN tag. In this way, the packet is transmitted to the
destination properly.
With the VLAN mapping function enabled, when the switch receives a packet tagged
with a network VLAN tag, it looks up the mapping rules configured for the matched
VLAN tag and then replaces the existing VLAN tag with the corresponding one (if the
matched mapping rule exists).
Figure 3-1
Figure 3-1 The structure of a packet tagged with a private network VLAN tag
Figure 3-2
Figure 3-2 The structure of a packet tagged with a public network VLAN tag
Different from VLAN VPN and selective QinQ, the VLAN mapping function does not
cause a packet to carry multiple VLAN tags. A packet is transmitted with only one VLAN
tag. Therefore, you need to make sure the private network VLAN tags can be restored
before customer packets enter the destination private network for customer packets to
be transmitted properly.

3.1.2 VLAN Mapping Implementation

You can configure VLAN mapping rules for each port of an S3100 series switch. With
the VLAN mapping function enabled on a port, the port maps private network VLAN
tags to the corresponding public network VLAN tags for packets to be forwarded to the
public network and performs the converse operation for the packets to be forwarded to
the destination private network.
shows the structure of a packet tagged with a private network VLAN tag.
shows the structure of a packet after VLAN tag replacement.
Chapter 3 VLAN Mapping Configuration
3-1