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Differences Between HP VLAN tagging and Cisco VLAN Terminology

HP VLAN Tagging Terminology Differences Defined

VLAN Modes

HP Procurve switches have four VLAN modes; "Untagged", "Tagged", "No", and "Forbid". Untagged mode is the equivalent of Access Mode in Cisco IOS terminology, which is used for end points, or devices not passing VLAN traffic forward (such as client ports; desktops, printers, etc.). Tagged mode is the same as Trunk mode in Cisco, which is used for ports that connect devices and are passing traffic forward (uplink or downlink ports on a switch or router). No mode means the physical port is not a part of the VLAN. Forbid mode restricts the port you added from communicating with that VLAN, regardless of any other tag setting.


The term Trunk means two different things when dealing with HP or Cisco equipment, so use this term with caution. HP Procurve switches use "trunk" to define a group of physical Ethernet ports, you trunk VLAN's from one phyical port to another, Cisco calls this a channel-group. Cisco uses VLAN trunk as a basic term to define what HP Procurve calls a Tagged port.


Both devices use 802.1Q standard VLAN identification. Older HP Procurve switches which are quite common, such as the HP Procurve 4000m, could only support a maximum of 8 VLANs. This basic feature when enabled, can add a little more functionality to an otherwise outdated, simple 10/100 switch. To enable VLAN support on your 4000m, you can easily telnet into the device, login as a manager, and turn on VLAN Support from the menu (it does require a reboot on these older switches). Today, you can setup up to 256 VLANs on a single modern HP Procurve switch (or router), however, a centrally located device, can pass (store) the tags of up to 4096 VLAN ids. VLAN 1 is the default administrative VLAN, this is set as "Untagged" on all ports out of the box. I generally leave it untagged on at least each uplink port, this save you from a tag mismatch conundrum (you may only have one VLAN in "untagged" in HP Procurve speak (access in Cisco speak) on any one port, which more or less requires every other VLAN to be "tagged" ("trunked" in Cisco speak) and passed on to the the next switch or router on an uplink port.

VLAN Names

HP Procurve switches allow up to 32 characters for the description, when you're looking at it in the menu view however, it will be truncated to 12 characters, so first 12 characters should begin with different descriptors so that there is some immediate distinction here. Typically, when I name them, I'll either call them the building or location they are located at, plus the number ID, e.g. building12. It's good to have both pieces of physical and virtual information to save yourself some confusion, and early on, so if you're viewing them in the trunicated view, you'll be able to quickly distinguish the difference.

Final words of wisdom, keep it simple, and avoid "spaghetti VLAN's". Feel free to contact us for consultation or advice with your HP and Cisco integration, we have years of experience building networks with both HP and Cisco equipment. Remote support is available and we have the ability to contract onsite.

Mini USB Keyboard for Android Tablets Without Bluetooth

Theses Mini USB keyboards should work with any Android devices connected though the built-in Mini USB port.

Physical Media Like Books, CDs, DVD's, Blu-Ray Losing Sales To Digital Media

Not a big surprise, but statistics now available from 2012 indicated the first time digital media sales have outpaced physical media sales of products like books, CDs, DVD's, Blue-ray, etc. Sony announced some time back that it halted producing actual CD's in their Japanese manufacturing plants due to the Japanese Earthquake in May of 2011, and never resumed production. Software distribution via download has all but completely replaced traditional software purchases in a brick and mortar store for some time and other media has followed this trend.

Economical TrendNet 48 Port Gigabit Unmanaged Switch - TEG-448WS

Without losing valuable rack space, the 48-port TrendNet Gigabit unmanaged switch manages to still be cost effective, doubling capacity of it's 24-port counterpart, but preparing your switch closet for more future expansion.

Economical TrendNet 24 Port Gigabit Unmanaged Switch - TEG-S24Dg

This Trendnet 24-port Gigabit Switch provides 24-port density occupying a 2U rack space. Brackets are available below to fit a standard 19" rack and are recommended to keep things securely attached.

Larger HDTV Options With Bracket

Conservatively priced, in the 42"-46" range, all are capable of changing to a TV station as well if needed as HDTV's are less expensive than actual monitors of this same size.

Downgrading Windows 8 to Windows 7 or Upgrading From Windows Vista Home to Windows 7 Pro

While primarily for business customers, Microsoft does have the option to downgrade your Windows 8 Pro Installation to Windows 7.

Another benefit this provides, is if you happen to find yourself in the unfortunate situation of being on a Home Edition of Windows Vista, you may upgrade to Windows 7 Home and retain all settings, after doing the upgrade to Windows 8, still retaining all settings, you may then downgrade to Windows 7 Pro. Thus doing the impossible, and going from Windows Vista Home to Windows 7 Pro and changing actual product lines (should you need the features of Pro and already own a valid license).

Western Digital MyBook Live 2TB USB 3.0 External Drive vs Seagate 2TB USB 3.0 External Drive

The Seagate 2TB USB 3.0 External Drive is a good cost conscious choice for 2TB of raw storage. Currently Seagate comes as a no-nonsense traditional storage device, while other manufacturers are focused on expanding the services they sell on top of just the drive, expanding the capabilities and functionality for their owners.

Though comparable in size, the Western Digital MyBook Live Drive has a lot more going for it and has more of the aforementioned functionality. Western Digital drives have traditionally outperformed Seagate drives of the same spindle speed but I won't get into that debate here. The Western Digital MyBook Live 2TB USB Drive also has a SmartPhone/Table App that will give your device access to your own personal storage on the go. Well worth the extra cost.

An Android App is now developed for the Western Digial MyBook Live product, your files stored on this device can now be available from anywhere you might need access to them, much the same way DropBox now functions but completely on your own secure devie.

Acer 27 Inch HDMI VGA DVI LED Flat Screen With Built In Speakers

This 27" Asus LED backlit LCD has 5-15 degrees of adjustment at the base and will still allow you to connect a bracket on the back to attach a standard 4-hole, either wall mount or zero client. It also has integrated speakers which helps to cut down on the clutter of external speakers. An HDTV of this same size should probably be less and adds that capability of a coax/cable tv port, but will have no included adjustable mount. Speakers on an HDTV would as well be integrated and was another major factor in selecting this particular model.

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