In a hub-and-spoke VPRN topology, two distinct Route Targets (RTs) are used to control route distribution. The hub PE exports its routes with one RT (the "hub" RT) and imports routes tagged with a different RT (the "spoke" RT). Conversely, all spoke PEs import the "hub" RT and export the "spoke" RT.

In this scenario, target:65100:1 acts as the "hub" RT, and target:65100:2 acts as the "spoke" RT. The command export target:65100:1 import target:65100:2 is configured on the hub PE (PE1) to advertise its routes to all spokes and accept routes from all spokes, establishing the required hub-and-spoke connectivity.

B. PE2, PE3 and PE4 are spoke PEs. They would be configured with the inverse RT policy (export target:65100:2 import target:65100:1) to communicate only with the hub.

C. Configuring this command on all PEs would not create the desired hub-and-spoke topology, as spokes would incorrectly export the hub RT.

D. This route target command structure is the fundamental mechanism for creating a hub-and-spoke VPRN and is therefore essential for the configuration.

1. Nokia 7750 SR OS Services Guide, Release 22.10.R1, "VPRN services" chapter, Section: "Hub and Spoke VPRN Topologies": This section explicitly describes the use of separate import and export route targets for hub and spoke sites. It states, "The hub site is configured to export its routes with a specific route target and import routes from all spoke sites... The spoke sites are configured to import the hub’s routes and export their routes to the hub site." This directly supports the configuration logic applied to PE1.

2. Nokia 4A0-106 Courseware, "Nokia Virtual Private Routed Networks Student Guide", Module 3: VPRN Service Implementation: The course material details VPRN topologies, including hub-and-spoke. Configuration examples show the hub PE exporting one RT and importing another, while spoke PEs have the reverse configuration, confirming the command in the question is for the hub PE.