ocr: Laver ranster acrms Mace Frane Relay eres PHoroat VONOEOT Lanel tentre virtanpatt Renonr ARARCICUR otacton Darat ti SCSntrer - covee DE a Paal Figure 2. MPLS uses existing label formats for ATM and frame relay forwarding. Everywhere else, ituses a generic label known as a Shim because it wedges between layer 2 and layer 3.