one way link exchange means once u r giving link to any website and in return u r not giving any link to your parent or child site that is example of one way linking Eg. article submission gallery or say directory Thanks
sometime webmaster like to link to for additional information scattered on internet for helping viewer to get more comprehensive understanding or another reason. If they don't ask for back link, then its one way link. But you ask for one way link exchange, i don't really know about that term, i only know about 3 way link exchange that mimicking the concept of one way link. Again i'm very new in SEO thing so maybe what i'm saying is not true at all..
Dear Friend, It is called "One way Linking" not "Exchange" one way link is, your site link you should post in other sites. Link exchange is, you should share each other's link
link exchange is when you like to a website and ask for a link back to yours on theirs, it helps with SEO and only after a quick few thousands/millions you may start seeing your site showing up high on google