The seller is the entity receiving the Purchase Order and responsible for fulfilling the order.
The seller of Carrier Ethernet wholesale access services is a CEN Operator that is willing to sell an E-Access service to a Service Provider that needs access to a Carrier Ethernet UNI that is on the seller's network, where the E-Access service connects between seller's UNI and the Service Provider's ENNI.
A global Tier 1 service provider called "GlobalSP" has an ENNI located in Cape Town, South Africa. GlobalSP needs to provide an E-Line service between a customer site in Chicago and another customer site in Johannesburg. A regional operator called SouthAfricaSP is able to provide an E-Access service between the Cape Town ENNI and a UNI located in the Johannesburg district where the customer site is located.