Layer 2 Protocol Tunneling

Configuring IEEE 802.1Q and Layer 2 Protocol Tunneling

IEEE 802.1Q Tunneling and Incompatibilities

Although IEEE 802.1Q tunneling works well for Layer 2 packet switching, there are incompatibilities between some Layer 2 features and Layer 3 switching.

•A tunnel port cannot be a routed port.

•IP routing is not supported on a VLAN that includes IEEE 802.1Q ports. Packets received from a tunnel port are forwarded based only on Layer 2 information. If routing is enabled on a switch virtual interface (SVI) that includes tunnel ports, untagged IP packets received from the tunnel port are recognized and routed by the switch. Customers can access the Internet through its native VLAN. If this access is not needed, you should not configure SVIs on VLANs that include tunnel ports.

•Fallback bridging is not supported on tunnel ports. Because all IEEE 802.1Q-tagged packets received from a tunnel port are treated as non-IP packets, if fallback bridging is enabled on VLANs that have tunnel ports configured, IP packets would be improperly bridged across VLANs. Therefore, you must not enable fallback bridging on VLANs with tunnel ports.

•Tunnel ports do not support IP access control lists (ACLs).

•Layer 3 quality of service (QoS) ACLs and other QoS features related to Layer 3 information are not supported on tunnel ports. MAC-based QoS is supported on tunnel ports.

•EtherChannel port groups are compatible with tunnel ports as long as the IEEE 802.1Q configuration is consistent within an EtherChannel port group.

•Port Aggregation Protocol (PAgP), Link Aggregation Control Protocol (LACP), and UniDirectional Link Detection (UDLD) are supported on IEEE 802.1Q tunnel ports.

•Dynamic Trunking Protocol (DTP) is not compatible with IEEE 802.1Q tunneling because you must manually configure asymmetric links with tunnel ports and trunk ports.

•VLAN Trunking Protocol (VTP) does not work between devices that are connected by an asymmetrical link or devices that communicate through a tunnel.

•Loopback detection is supported on IEEE 802.1Q tunnel ports.

•When a port is configured as an IEEE 802.1Q tunnel port, spanning-tree bridge protocol data unit (BPDU) filtering is automatically enabled on the interface. Cisco Discovery Protocol (CDP) and the Layer Link Discovery Protocol (LLDP) are automatically disabled on the interface.

The following are configuration guidelines and operating characteristics of Layer 2 protocol tunneling:

•The switch supports tunneling of CDP, STP, including multiple STP (MSTP), and VTP. Protocol tunneling is disabled by default but can be enabled for the individual protocols on IEEE 802.1Q tunnel ports or access ports.

	Catalyst 2960-XR Switch VLAN Configuration Guide, Cisco IOS Release 15.0(2)EX1
122	OL-29440-01

WSC2960XR48FPSI specifications

The Cisco WSC2960XR48FPSI is an advanced, high-performance switch that plays a vital role in today's enterprise networking environments. Designed for reliability and efficiency, it serves as a foundational component for organizations concentrating on network agility and scalability.

One of the standout features of the WSC2960XR48FPSI is its ability to support 48 Gigabit Ethernet ports, facilitating high-speed connectivity across multiple devices. This capacity makes it an ideal choice for enterprises that require robust network infrastructure to handle large volumes of traffic effortlessly. Additionally, it includes two 10-Gigabyte SFP+ uplink ports, providing enhanced bandwidth for backbone connections, enabling seamless integration with data center environments.

The switch supports Cisco's StackPower technology, which allows multiple switches to share power resources. This capability not only provides redundancy but also ensures that organizational networks can be efficiently managed, reducing operational costs by utilizing power resources wisely.

In terms of reliability, the WSC2960XR48FPSI offers a fanless design, making it an optimal choice for deployments in noise-sensitive environments such as classrooms or offices. Its features include support for Cisco's FlexStack-Plus technology, which allows for easy stacking of up to eight units. This results in simplified management and increased bandwidth as switches in the stack operate as a single entity.

The switch is powered by Cisco IOS Software, providing robust features, including advanced security protocols, quality of service (QoS) capabilities, and comprehensive network management tools. With support for multicast routing and enhanced security, organizations can safeguard their data while ensuring smooth and reliable communication across applications.

Moreover, the Cisco WSC2960XR48FPSI is designed to be energy-efficient, compliant with IEEE 802.3az Energy Efficient Ethernet standards, which aids in reducing power consumption without sacrificing performance. This commitment to sustainability makes it a favorable option for organizations striving for greener operations.

To summarize, the Cisco WSC2960XR48FPSI is an exemplary model of reliability, scalability, and performance. Its sophisticated features, including high port density, advanced security measures, and energy efficiency, make it a cornerstone for modern enterprise networks, enabling organizations to adapt effectively in an ever-evolving digital landscape.

Cisco Systems WSC2960XR48FPSI manual Ieee 802.1Q Tunneling and Incompatibilities

Models: WSC2960XR48FPSI

IEEE 802.1Q Tunneling and Incompatibilities

Related Topics

Layer 2 Protocol Tunneling

OL-29440-01

WSC2960XR48FPSI specifications