I bet the person really meant Linksys which is owned by Cisco and supports "guest access".
Here's a good article about it:
The feature has been on the Linksys products over the last several years, the article lists the model ranges that have it (and doesn't list the newest hardware since they weren't available when the article was written).
As the article notes, you'll have to install their software to set up that feature, as opposed to merely pointing your web browser at the address of the router and using its built-in management screens, but using that software isn't a bad idea in any case, especially for initial setup.
As for what to get, I own a slightly older version of this model:
and have recommended it to others, and feel it's well worth the $77 that Amazon asks for it. The setup software that it does want you to install is very easy to use. I recommended it to a friend who is not computer literate, and expected him to be calling me with questions, but he got it online with no issues at all!
You can probably find refurbed or used models of this or similar ones all around the Internet if you want to save money i.e. E3200 is quite similar to EA3500 in features but is discounted because it's the previous generation hardware.
The highest model EA4500 only differs from EA3500 by being 450+450 vis 300+450 (meaning both have dual-band radios but the higher end one has one radio that can do 450 megabits instead of 300) which should only matter if your guests are downloading tons of HD
video. It also has a built-in media server, but that really shouldn't be a factor for you, because if you really need a media server there are better ways to go. The EA4500 costs twice as much at Amazon's prices but doesn't deliver 2x value, IMHO:
Of course there are other brands out there and it's a very competitive space so most of the major brands offer very good price performance and features. That said, I'm quite happy with the price/performance of the Cisco/Linksys E3500 and they are so widely used there is no problem getting online help from geeks like me.