Wireless printer service process
Process overview of service for a wireless printer:
Procedure
1.
Wireless Printer 1 sends an mDNS response advertising printer services in Switch 1 on VLAN 1.
2.
Switch 1 has no inbound filter in VLAN 1. The global filter set to
permit all
.
3.
Switch 1 checks the outbound filter in VLAN 1. As there is no specific outbound filter, the global status is
permit all
. It will flood the packet in VLAN 1 except the source port.
4.
iPhone 1 in VLAN 1 receives the service announcement.
5.
Switch 1 checks the reflection status. Reflection is enabled on VLAN 2 and 3.
6.
Switch 1 checks the outbound filter in VLAN 2. As there is no specific outbound filter, it will forward the
service announcement in VLAN 2.
7.
Default action
permit all
.
8.
Switch 1 checks the outbound filter in VLAN 3. The outbound filter is set to
deny wireless printer
therefore
the packet will not be forwarded to VLAN 3.
9.
Switch 3 receives the service advertisement in VLAN 2. It will flood the packet in VLAN 2 except the source
port.
10.
Host 2 in Switch 3 receives the service announcement.
Wireless Printer advertising printer service
The following procedure depicts an advertising service process for a wireless printer in the form of an example.
Procedure
1.
Wireless Printer 2 sends an mDNS response advertising printer services in VLAN 3.
2.
Switch 2 does not have any inbound filter in VLAN 3, so it receives the wireless printer service announcement.
3.
Switch 2 checks the outbound filter in VLAN 3. There is no specific outbound filter on VLAN 3, so it floods the
service announcement in VLAN 3 (except at the source port.)
4.
Switch 2 checks the reflection status. Since switch 2 is not enabled, switch 2 does not forward.
5.
As there is no inbound filter in VLAN 3 of switch 1, it receives the service announcement on VLAN 3. When
switch 1 checks the outbound filter in VLAN 3, there is
deny operation for service type wireless
printer
error message. Therefore switch 1 will not flood the packet in VLAN 3.
6.
Switch 1 checks the reflection status. The reflection is enabled on VLAN 2 and 3 however VLAN 3 is incoming
so the reflection will not function. In VLAN 2 it checks the outbound filter. There is no outbound filter in VLAN 2
so switch 1 forwards the service announcement in VLAN 2.
7.
Switch 3 does not have any inbound filter therefore It receives service announcements in VLAN 2.
8.
Switch 2 checks the outbound filter in VLAN 2. As there is no specific outbound filter, the global action is to
permit all
so switch 2 floods the packet in VLAN 2 (except the source port.)
9.
Host 2 receives the switch 2 print service announcement.
Appendix A Apple’s Bonjour and Google’s Chromecast
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