IS-IS Hello Padding

Table 1. IS-IS Hello Padding

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 4450 Series	VOSS 8.2.7
	VSP 4900 Series	VOSS 8.2.7
	VSP 7200 Series	VOSS 8.2.7
	VSP 7400 Series	VOSS 8.2.7
	VSP 8200 Series	VOSS 8.2.7
	VSP 8400 Series	VOSS 8.2.7
	VSP 8600 Series	Not Supported
	XA1400 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.