BROCADE IP PRIMER

PowerPower49F Link 50FConsole1 3 5 7 9 1113 15 17 19 21 2325 27 29 31 33 3537 39 41 43 45 471F 2F 3F 4F2 4 6 8 10 1214 16 18 20 22 2426 28 30 32 34 3638 40 42 44 46 4849F Link 50FConsole1 3 5 7 9 1113 15 17 19 21 2325 27 29 31 33 3537 39 41 43 45 471F 2F 3F 4F2 4 6 8 10 1214 16 18 20 22 2426 28 30 32 34 3638 40 42 44 46 48Dual Port ModeThe port is now a member of the default VLAN.The important thing to remember is that whether or not you have any VLANsconfigured on your switch, all Brocade switches have at least one VLAN.Dual Port ModeFeeling comfortable with VLANs now? Let's turn it up a notch then. Rememberhow I said that a single interface could either be a tagged or untagged memberof a VLAN? Well, I left out one other possibility: it can be both. On aBrocade switch, a single port may be an untagged member of one VLAN, and atagged member of one or more different VLANs.“Both?!?” I hear you cry, “Why in the world would any rationally thinking humanbeing do such a thing?!?” Well, let's look at an example:VOIPHere, we have a Voice-over-IP (VoIP) phone. Most models of these phones havean additional pass-through network port on them. This makes it easier foroffices or cubicles that have only one network port. That one port can nowhouse both the phone, and the workstation. The workstation will plug into thephone, and the phone will plug into the network port on the wall.The problem? Well, it's common to have an entirely separate VLAN (oftenaccompanied by an entirely separate network) for the VoIP phones. Let's say,the phone's VLAN is VLAN 50. Then the workstation needs to be in VLAN 10.“What's the problem?” you say, “Just tag the switch port as members of bothVLANs.” Well, that is one solution. The problem? If the switch port is tagged,the connected devices have to be tagged, too. Now, a phone, as in almost anynetwork appliance can be easily tagged. A workstation, on the other hand, isnot nearly so simple. In fact, on most operating systems, it is not in the leastbit easy, nor desirable, to 802.1q tag your workstation's NIC. This is particularlyundesirable with a novice, or even an intermediate level, user. By default,and in the vast majority of configurations, the workstation is untagged. Whatdo we do?VOIPdual-porttagged VLAN 50untagged VLAN 10taggedVLAN 50untaggedVLAN 10We configure the switch port to be in dual port mode. This way, it will be anuntagged member of VLAN 10 (for the workstation), and it will be a taggedmember of VLAN 50 (for the phone). We will need to configure the phone to beBrocade IP Primer 181