Tips #4 - vlan expressions for documentation

If you have a network running through your house like I do, and have vlans as part of it, then you probably have some so called "trunk" Ethernet cables.  So how do you explain what vlans are where?  This is what I do:

• A port on a router or a switch that has an untagged vlan is noted with brackets around the vlan number like [4] for an untagged port with vlan4 present.
• When designating a "trunk" port on a router or a switch you have tagged vlans and you have a PVID assigned.  I put the PVID first, to know what vlan is used when there is no tagging, a slash, and then a T followed by a list of each of the vlans that are tagged on that port.  So it looks like [6/T4,8,88,123-124,152] for a PVID of vlan6 with tagged vlans: 4, 8, 88, 123, 124, and 152.  I still put brackets around the values to designate that these are vlans I am dealing with.  I use the dashes as a shorthand noting that this includes all of the vlan numbers in between.
• I generally like to make the "trunk" lines between switches and routers have a standard grouping of vlans.  In that way, a shorthand would be [6/T] where the tagged vlans are common across the entire network.
• When I use "trunk" lines, I like to reserve a couple of vlans for specific purposes other than normal traffic.  
• I use vlan850 as a shorthand in a switch to denote that the ports that use vlan850 are all untagged and serve as a short unmanaged switch.  I never allow vlan850 to be included in any "trunk" configurations.
• I use vlan11, always untagged, as a dead port designation.  What this means is that vlan11 does not get assigned to any "trunk" configuration and serves to simply block a port from being useful when it is not used.
• I use several vlans, for example 66 through70, as temporary patch vlans.  What this means is that I can attach an untagged port to a switch on one end of the house and an untagged port to a switch on the other end of the house and effectively have a "patch cable" in between the ports.  One caution, normally you cannot assign one end to the same port as a monitor port on a switch, at least I haven't figured out how to yet.