By "router leg" they mean a (directly) connected route (and use a strange way of putting it).
What is a connected route compared to a static route?
Connected route (router leg)
A connected route is a route that points to an interface. For example if you configure 10.0.0.1/24 on (ethernet) interface Gi0/1 the directly connected route (the "router leg") is 10.0.0.0/24.
If the router wants to send a packet to a host in the 10.0.0.0/24 network it will do a L2 (Layer2) lookup (ARP for IPv4, ND for IPv6) on the Gi0/1 interface to find the MAC address of the host. It will then send the packet to the MAC address.
One-liner: Connected routes point to an interface, next-hop for packet will be resolved at L2 by ARP/ND on the respective interface.
Static route
A static route points to an IP address. For example you could have route 10.0.0.0/24 pointing to 10.0.2.1. The router will send packets for hosts in the 10.0.0.0/24 network to 10.0.2.1.
For this to work 10.0.2.1 itself must be part of a connected route so that the router can find the right L2 next-hop for the packets.
One-liner: Static routes point to an IP next-hop. The IP next-hop itself will be resolved by L2 lookup on the interface the connected route for the next-hop points to.
One thing you should ask your vendor: If the specs are for IPv4 and for IPv6, and if not how many IPv6 routes you can have for each of the different types.
By default, a layer 3 switch will treat broadcasts like a layer 2 switch at the layer 2 level. IOW, it will forward the broadcast throughout the VLAN. By default, it will treat broadcasts like a router at the layer 3 level. IOW, it will not forward broadcasts across layer 3 boundaries.
Best Answer
You need to understand the difference between layer-2 and layer-3 for an answer to have any real meaning for you, and I suspect you don't.
A layer-2 network is a LAN, and all hosts on it are peers. A LAN is bounded by layer-3. The layer-2 frames are delivered to the host with the destination MAC address in the frame. I one host wants to send something to all the hosts on the LAN, it will address the frame(s) with the
ffff:ffff:ffffMAC address. Each host is obligated to strip the frame and inspect the packet to see if the packet is meant for it.A layer-3 network is usually, but not always, on a layer-2 LAN. Router use layer-3 to send packets between LANs. A host on a LAN cannot send a layer-3 packet without first encapsulating it in a layer-2 frame, and that requires layer-2 MAC addresses.
You need ARP (or an equivalent, see IPv6) to resolve the layer-3 address to a layer-2 address. When a host sends a packet to another host on the same LAN, it first looks in its ARP cache to see if it has a layer-2 address for the layer-3 address. If it does not, it sends an ARP request. The ARP request is broadcast at layer-2 to all hosts on the LAN, looking for the host which owns the layer-3 address. The host owning that address will respond with an ARP reply, giving the requesting host its MAC address. In this case, a layer-2 broadcast gets the attention of all the hosts on the LAN, but only the host with the layer-3 address responds.
A layer-3 broadcast packet is meant for all hosts on the layer-3 network. When a host needs to resolve the layer-3 broadcast, it uses the layer-2 broadcast address for the frame.
There are two types of layer-3 broadcast: the limited broadcast,
255.255.255.255, as you noted, and the network broadcast, the highest IP address in a network. The limited broadcast can never cross a router, while a network broadcast may cross a router if the router has been configured that way, although that is considered a security risk, and routers do not allow this, by default, but that was not always the case.