Key Pointers to Remember when Installing for an Apartment, Motel or Hotel and etc.
October 11th, 2007In a MDU and MTU installation ensure that VLAN separation is not only on the DSLAM but also on the switches that provide the uplinks to the DSLAMs. The switches must be set to ensure their ports do not allow clients in separate DSLAM’s to be able to be detected or reached by others.
We see these mistakes all the time when supporting clients that purchase our DSLAM’s. They will discover somehow when deploying multiple DSLAMs in a phone room that links to clients that links are unstable, random and the IP’s being handed out by the DHCP are just as bizarre. This can happen when clients plug their modems to routers or wireless routers in their own network which would also send it upstream, though the users on the same DSLAM are protected, users on all other DSLAMs are now vulnerable to receiving IP’s from that user’s router. Creating a real snafu for the network and at first most will believe it’s the DSLAM that is dropping links or creating unstable internet connections.
Summary:
Though not by intent, forgetting to VLAN or concentrate users up the Entire chain of equipment that are providing internet to users in a MTU or MDU can be fatal. Especially in conditions where users can opt to choose your service or a cable company right away, and if at the very start random errors like this will destroy a lot of credibility and worse, income that could have so easily been yours.
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What are VLANs?
October 11th, 2007VLAN which stands for Virtual LAN is defined in the IEEE802.1q standard. It is a technology allowing a company or an individual to extend their LAN over the WAN interface, breaching the physical limitations of regular LANs.
VLAN technology also allows having several VLANs over a single switch in such a manner that all the LANs will operate in parallel and may not be even aware of each other.
VLAN as can be inferred from the name allows you to create a virtual LAN as far as the users are concerned behaves the same way as a regular LAN does. For instance someone in New York could access a printer located in Tel-Aviv using a LAN IP address - as if the printer were just in the next room!
There is more reading you can do on VLAN’s, explaining the tagged or framed based or port based VLAN’s and so forth. Cisco has their own definition which most of the world follows, but HP has its own as well, so its up in the air which is the Law. Googling online will bring forth a ton of articles explaining the many virtues and styles of VLAN available. However for all intents and purposes for the environment and the purposes of what we intend here, VLAN = Goodness.
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What in the world is VLAN, or Client Separation and Who needs it!?!?!
October 11th, 2007Crunch time is here, the switches are up and running, DSLAM’s are connected and modems are synched. About 5000 students from fresh faced freshmens to salted seniors are about to move into their apartments and soon data will be busting through the student housing complex as the flurry of desktops and laptops start pounding at sites like Facebook and Youtube and other bandwidth heavy streaming sites,
Then disaster strikes, virus infections start multiplying, DHCP addresses never even imagined possible begin flooding and baffling modems left and right. Cries of outrage and sheer despair begin to dot the student housing complex as modems, laptops, network equipment of all kinds are flung out dorm windows and support center hotlines are backed up to a 45 minute wait time. Multiple routers seem to be on the network and gateways and DSLAMs are burning up as the mass confusion has the switches now sending packets to all directions of the wind.
At the end of it once all the havoc dies down and careful study begins to reveal the source of the problems… no as it turns out it is not a uber hacker exchange student from the Ukraine or a long range cyber penetration from the Chinese middle kingdom messing with our college kids.. but oversight.
It is all about VLANs, client separation and how every one needs it yet how often it can be overlooked is quiet startling to say the least.
At the very primitive level VLANs as it matters to MDU and MTU installers, can be described as the virtual separation that prevents users connected on a DSLAM or switch from being able to reach or connect to one another and the intent of doing so is to prevent malicious hacks or virus suppression as well as DHCP from multiple routers flooding the networks.
Note also that sometimes key terms and descriptions may vary for the same intent, for example concentration mode is another name for client separation and sometimes VLAN separation is also used to describe the same requirement.
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