SNR S2989G-8TX — настройка и применение технологии Dot1q-tunnel для сетей [135/553]

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S2989G-24TX Operation Manual Chapter 2 Layer 2 services

Configuration

should be assigned for the same network user on different PEs. When packet reaches

PE1 from CE1, it carries the VLAN tag 200-300 of the user internal network. Since the

dot1q-tunnel function is enabled, the user port on PE1 will add on the packet another

VLAN tag, of which the ID is the SPVID assigned to the user. Afterwards, the packet will

only be transmitted in VLAN3 when traveling in the ISP internet network while carrying two

VLAN tags (the inner tag is added when entering PE1, and the outer is SPVID), whereas

the VLAN information of the user network is open to the provider network. When the

packet reaches PE2 and before being forwarded to CE2 from the client port on PE2, the

outer VLAN tag is removed, then the packet CE2 receives is absolutely identical to the

one sent by CE1. For the user, the role the operator network plays between PE1 and PE2,

is to provide a reliable layer-2 link.

The technology of Dot1q-tuunel provides the ISP internet the ability of supporting

many client VLANs by only one VLAN of theirselves. Both the ISP internet and the clients

can configure their own VLAN independently.

It is obvious that, the dot1q-tunnel function has got following characteristics:

 Applicable through simple static configuration, no complex configuration or

maintenance to be needed.

 Operators will only have to assign one SPVID for each user, which increases the

number of concurrent supportable users; while the users has got the ultimate

freedom in selecting and managing the VLAN IDs (select within 1~4096 at users’

will).

 The user network is considerably independent. When the ISP internet is

upgrading their network, the user networks do not have to change their original

configuration.

Detailed description on the application and configuration of dot1q-tunnel will be

provided in this section.

2.15.2

Dot1q-tunnel Configuration

Configuration Task Sequence of Dot1q-Tunnel:

1. Configure the dot1q-tunnel function on port

2. Configure the protocol type (TPID) on port

1. Configure the dot1q-tunnel function on port

Command

Explanation

Port mode

dot1q-tunnel enable

no dot1q-tunnel enable

Enter/exit the dot1q-tunnel mode on

the port.