Q: Please advise if practical to use Airport Extreme to extend wireless network in a large home.

You can use Airport Express' to extend a wireless network created by an AEBS. If the AEBS is a tower model then it supports 802.11AC, but the older flat ones do not. New AEX's do support 802.11AC, but that is of little use if the AEBS model does not.

You seem to be looking for optimum performance.......which can only be achieved using wired Ethernet cable connections between the various wireless "access points" around the home.

Do you have Ethernet cabling installed in your home now?  If not, is it something that you can consider?  Or, is it simply out of the question?

Not sure whether you want to have good wireless coverage throughout your home, but to give you an idea of what might be required.....my home is about 2200 square feet on 2 levels, and it takes a minimum of 3 wireless access points to provide good wireless coverage throughout the house, plus a fourth access point for the outside patio area.

Unless you have your mind made up on a home network, probably the best investment that you could make at this time would be to enlist the services of an IT professional to come to your house to survey the complete area and come up with a proposal that would deliver the type of performance that you want.

For example, if you were planning to use wireless connections between AirPorts to "extend" your network, your plan to have an "original" device, an "intermediate" device and "final" device will simply not work......because Apple only allows the network to be extended one time using a wireless connection.

You also might not realize that when you use a wireless connection to extend a network, about half of the potential speed on the network will be lost in the process.  This speed loss can be avoided by using wired Ethernet cable connections between the various AirPorts.

I suspect that an origin device connected to the cable modem...an intermediate device....and a final device in a location most distant from the origin device would be required.

The method that AirPort base stations extend a Wi-Fi network will differ when the base stations are interconnected by Ethernet or by wireless. If wireless is your desired goal, then it is important to understand how they do this. Think of an old fashioned wagon wheel.

Basically, the "main" base station (the one connected to the Internet modem) would be at the hub of this wheel and each extending base stations would be on the spokes. What this means is that you cannot "daisy-chain" them to cover a long range, like one end of a house to the other. All extending base stations can only extend the "main."

To get around this, you would want to interconnect them all by Ethernet ... if possible for your home.

The two different methods are known as "extend" (all wireless connections) and roaming (all wired connections.) Let us know which you would prefer to pursue and we can assist you with setting it up. Note: The overall wireless performance will be much better with the roaming type.

I would check with the local Apple Store to see if they have some recommendations for you. An authorized Apple Repair Shop would be another place to ask.

Another excellent source would be a CEDIA specialist.....who is well versed in home automation, security, entertainment, IT and other categories.

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