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What is VLAN translation?
VLAN translation, or VLAN rewrite, allows you to configure bidirectional VLAN identifier translation with a list on frames arriving on and leaving from a logical interface. This lets you use unique VLAN identifiers internally and maintain legacy VLAN identifiers on logical interfaces.
What is VLAN normalization?
VLAN Translation (Normalization) for VPLS Services A packet received on a physical port is only accepted for processing if the VLAN tags of the received packet match the VLAN tags associated with one of the logical interfaces configured on the physical port.
How does ARP work with VLANs?
ARP is sent by the client, the client typically has no knowledge of what VLAN it is a member of. It is therefore unable to add a VLAN tag, and shouldn’t be expected to. The ARP the client sends will arrive on the switch untagged. If the switch sends the frame out a trunk port, the switch will add a VLAN tag.
What is VLAN mapping in Cisco?
On an interface configured for VLAN mapping, the specified C-VLAN packets are mapped to the specified S-VLAN when they enter the port. One-to-one VLAN mapping occurs at the ingress and egress of the port and maps the customer C-VLAN ID in the 802.1Q tag to the service-provider S-VLAN ID.
What is S VLAN and C VLAN?
VLAN Translation includes the VLAN tunneling feature and the VLAN mapping one to one feature. This feature is known as “double tagging” or QinQ, because in addition to the regular 802.1Q tag (Customer VLAN/C-VLAN), the switch adds a second ID tag known as a Service Tag (S-VLAN), to forward traffic over the network.
What is VLAN tunneling?
802.1Q tunneling enables service providers to use a single VLAN to support customers who have multiple VLANs, while preserving customer VLAN IDs and keeping traffic in different customer VLANs segregated. A port configured to support 802.1Q tunneling is called a tunnel port.
What is VLAN CCC?
vlan-ccc—Use VLAN CCC encapsulation on Ethernet interfaces with VLAN tagging enabled. VLAN CCC encapsulation supports TPID 0x8100 only. You must configure this encapsulation type on both the physical interface and the logical interface. VLAN ID 0 is reserved for tagging the priority of frames on all Ethernet PICs.
What is VLAN swap?
(VLAN translation (swapping) replaces an incoming C-VLAN tag with an S-VLAN tag instead of adding an additional tag.
Do switches use ARP?
The switch maintains an ARP table which is made of mapped IP addresses and MAC addresses. When a packet needs to be routed to a certain device, the switch looks up the IP address of the device in its ARP table to obtain the MAC address of the destination device. The ARP table includes both static and dynamic addresses.
What is layer 3 ARP?
The Layer 3 switch places the information from the ARP response into the ARP cache. ARP requests contain the IP address and MAC address of the sender, so all devices that receive the request learn the MAC address and IP address of the sender and can update their own ARP caches accordingly.
What is a VLAN map?
VLAN Mapping provides a mechanism for Service Providers to translate CVLANs to SVLANs when a packet enters its network and vice-versa, when it leaves the network. VLAN translation is enabled on a per-port basis, where a CVLAN is mapped to an SVLAN.