Outlines encapsulation methods used with TLOCs, describing encapsulation types and their significance in TLOC transport configurations.
An encapsulation is a required configuration on Cisco IOS XE Catalyst SD-WAN devices that
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specifies the tunnel encapsulation type as either IPsec or GRE, and
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sets the default MTU to 1442 bytes for IPsec and 1468 bytes for GRE, which is enabled by default on all TLOCs, based on BFD path MTU discovery.
You can configure both IPsec and GRE encapsulation by including two encapsulation commands under the same tunnel-interface command. On the remote Cisco IOS XE Catalyst SD-WAN device, you must configure the same tunnel encapsulation type or types so that the two routers can exchange data traffic. Data transmitted out of an IPsec tunnel can be received only by an IPsec tunnel, and data sent on a GRE tunnel can be received only by a GRE tunnel. The Cisco Catalyst SD-WAN software automatically selects the correct tunnel on the destination Cisco IOS XE Catalyst SD-WAN device.