Ethernet packet in L2 switch

eric.huihk · ‎08-02-2007

HostA is connecting in L2 switch. When host A sent out a packet,is the packet broadcast to all hosts of the vlan? If no host of the L2 switch reply, then is it will forwarded to the Gateway?

PatsFan12 · ‎08-02-2007

Is this a VLAN (native) within a switch or a trunked VLAN going across multiple routers?

eric.huihk · ‎08-02-2007

What differences between native vlan and trunked vlan?

Anyway, there is a connection for this L2 switch to the Gateway.

mhellman · ‎08-03-2007

Generally speaking, and making a lot of assumptions about the details...no.

A unicast packet will go directly to either:

1) the MAC address of a host on the same VLAN

2) the MAC address of a router that can get to that host (including a default gateway)

However, if a switch receives a frame with a destination MAC not in its CAM table, it will send the frame out on all ports.

Jagdeep Gambhir · ‎08-06-2007

Yes, if Switch don't have a mac address in its CAM then it will broadcast to all ports on a vlan including gateway.

Check this link,

http://www.cisco.com/en/US/tech/tk389/tk390/technologies_tech_note09186a00800a7af3.shtml#switchtechs

Please rate if that helps

Regards,

~JG