I could ping/telnet to it not only from a host on the same subnet, but also from hosts on remote subnets. I was also puzzled to know that even though I did not configure a default gateway (using the ip default-gateway command) on my Catalyst 2960 L2 Switch. When I want to Telnet to the switch, I set the IP address of the VLAN Multicast doesn't cross layer-3 boundaries, either, unless a router is configured to route multicast (off by default). This doesn't interrupt every host on the LAN, and it, in all probability, with only hit the host for which it wants to resolve the layer-2 address. IPv6 does basically the same thing, but IPv6 doesn't have broadcasts, so it uses a special multicast group based on the last 24 bits of the IPv6 address. If the destination is on a different layer-3 network, the host (including the switch management) will send the frame to the gateway's layer-2 address. The host (including the switch management) can tell if the destination layer-3 address is outside its network because it has its own layer-3 address, the destination layer-3 address, and the network mask of its network. Broadcasts do not cross layer-3 boundaries (routers). The host (including the switch management) sends an ARP (Address Resolution Protocol) request via a broadcast to do the resolution. When a host (including the switch management), wants to send a packet to another host, it needs to resolve the layer-3 address (IP, etc.) to the other host's layer-2 address (MAC, etc.) in order to build a layer-2 frame. Without a default gateway, the switch management address (on VLAN 1 in your case, but it could be on any VLAN configured on the switch) cannot send traffic off its network to another network. The default gateway on a switch has the same function as any gateway configured on a host PC. Telnet is a bidirectional protocol, and the switch, without the default gateway, would be unable to respond to the host which is attempting to establish the Telnet session. The switch management cannot send anything to a different layer-3 network without a default gateway.