Allow specific IP to access link using ASM

I assume that by "a link" you are talking about a web application already behind F5 LTM/ASM and not an external link like "facebook.com".

If "a link" if a web application behind BIG-IP then the answer is - yes, it can be done, but it is a massive overkill if it is ALL you want to do. It is like hitting a nail into the wall with a bulldozer :)

If access by specific IPs is all you need then the simplest thing to use is a traditional firewall or AFM. ASM is there to protect Web Applications from hacker attacks, not to act as an IP packet filter :)