| Feature | Product | Release introduced | 
|---|---|---|
| IS-IS hello padding (ability to disable) | 5320 Series | Fabric Engine 8.6 | 
| 5420 Series | VOSS 8.4.2 | |
| 5520 Series | VOSS 8.2.7 | |
| 5720 Series | Fabric Engine 8.7 | |
| 7520 Series | Fabric Engine 8.10 | |
| 7720 Series | Fabric Engine 8.10 | |
| VSP 4900 Series | VOSS 8.2.7 | |
| VSP 7400 Series | VOSS 8.2.7 | 
To detect maximum transmission unit (MTU) mismatches, Intermediate System-to-Intermediate System (IS-IS) pads hello packets to the full interface MTU. All hello packets on Fabric Extend network-to-network interface (NNI) links are padded . On non-Fabric Extend point-to-point NNI links, hello packets are padded until a hello packet is received from the other side.