Chapter 29 Layer 2 Protocol Tunneling

Table 92 Advanced Application > Layer 2 Protocol Tunneling (continued)

LABEL

DESCRIPTION

*

Use this row to make the setting the same for all ports. Use this row first

 

and then make adjustments on a port-by-port basis.

 

Note: Changes in this row are copied to all the ports as soon as you

 

make them.

 

 

CDP

Select this option to have the Switch tunnel CDP (Cisco Discovery

 

Protocol) packets so that other Cisco devices can be discovered through

 

the service provider’s network.

 

 

STP

Select this option to have the Switch tunnel STP (Spanning Tree Protocol)

 

packets so that STP can run properly across the service provider’s

 

network and spanning trees can be set up based on bridge information

 

from all (local and remote) networks.

 

 

VTP

Select this option to have the Switch tunnel VTP (VLAN Trunking Protocol)

 

packets so that all customer switches can use consistent VLAN

 

configuration through the service provider’s network.

 

 

Point to Point

The Switch supports PAgP (Port Aggregation Protocol), LACP (Link

 

Aggregation Control Protocol) and UDLD (UniDirectional Link Detection)

 

tunneling for a point-to-point topology.

 

Both PAgP and UDLD are Cisco’s proprietary data link layer protocols.

 

PAgP is similar to LACP and used to set up a logical aggregation of

 

Ethernet ports automatically. UDLD is to determine the link’s physical

 

status and detect a unidirectional link.

 

 

PAGP

Select this option to have the Switch send PAgP packets to a peer to

 

automatically negotiate and build a logical port aggregation.

 

 

LACP

Select this option to have the Switch send LACP packets to a peer to

 

dynamically creates and manages trunk groups.

 

 

UDLD

Select this option to have the Switch send UDLD packets to a peer’s port

 

it connected to monitor the physical status of a link.

 

 

Mode

Select Access to have the Switch encapsulate the incoming layer-2

 

protocol packets and forward them to the tunnel port(s). Select Access

 

for ingress ports at the edge of the service provider's network.

 

Note: You can enable L2PT services for STP, LACP, VTP, CDP,

 

UDLD, and PAGP on the access port(s) only.

 

Select Tunnel for egress ports at the edge of the service provider's

 

network. The Switch decapsulates the encapsulated layer-2 protocol

 

packets received on a tunnel port by changing the destination MAC

 

address to the original one, and then forward them to an access port. If

 

the service(s) is not enabled on an access port, the protocol packets are

 

dropped.

 

 

Apply

Click Apply to save your changes to the Switch’s run-time memory. The

 

Switch loses these changes if it is turned off or loses power, so use the

 

Save link on the top navigation panel to save your changes to the non-

 

volatile memory when you are done configuring.

 

 

Cancel

Click Cancel to begin configuring this screen afresh.

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XGS-4526/4528F/4728F User’s Guide