From TFA the attorney for TR Labs, George Summerfield stated:
"In fact, all of the claims and all of the patents are directed at a communications network, not the particular switching nodes that are manufactured by Cisco and the other companies that are subject of our claims,"
If you read that as is without any a deeper explanation I get the idea that TR Labs can sue anyone who has a communications network.
Again from TFA:
The patents TR Labs is asserting are U.S. Patent Numbers 4,956,835; 5,850,505; 6,377,543; 6,404,734; 6,421,349; 6,654,379; 6,914,880; and 7,260,059.
Am I going to look at those patent numbers? No ! I don't want to get get a migraine headache since many modern IT patents are written in "legalese" such that someone with a Professional Engineering (yes a real one) background who is actually conversant with the field has a hard time understanding the words. Of course the opposite applies since most legal people can understand the words but not the context.
Ok I did look at patent 4,956,835 and it was just like I thought it would be which is basically an implementation and still requires hardware which manufacturers like Cisco provide. The following is an intro:
The present invention relates, in general, to a method and apparatus for rapidly effecting, in a communications network, the restoration of communications between nodes whose interconnecting spans have failed for one reason or another.
I particularly like fig 1c which basically a stylised drawing of the USA (well worth the LOL look) - see here and click on fig "1c" of Images which is the second image from the left.