Posted by: Pdfprep Category: 300-320 Tags: 300-320 exam questions, 300-320 practice exam, CCDP Post Date: November 28, 2020 Pdfprep2020-11-28T11:24:53+00:00 In which OSI layer does IS-IS operate?A . Layer 1B . Layer 2C . Layer 3D . Layer 4 View Answer Answer: B Author Pdfprep