Earlier, it was tough that the person who works remotely cannot socialize at all! Neither would his network be broad. It would actually be in the limited domain. However, a person who does not work as a permanent employee does not mean can not have a wide network of acquaintance. He too can have a lot of connections if he takes care of the followings:
In a remote working situation, the interactions require greater effort than the employees who are not the virtual employees. In such circumstances, it is important to make real and genuine relationships. This is possible by being available always and at all possible times the boss pings. It can also be made possible by maintaining relations with other employees of the company by exchanging gifts on festivals and by exchanging greetings one every now and then.
All this is not difficult to maintain. Using the world of technology, one can get the most benefit. Google Hangouts, WhatsApp calling feature, Skype allow one to have face to face interaction as if the person is available there itself.
I remember one of my friends being removed from the job for just not picking up his boss's call at urgent times. Nowadays, flattering has become the key to many endeavors. Hence, you might not completely devote yourself to woo others but you must make yourself available to volunteer at office events and socializing activities.
If the network building has to be done with people from outside the company, it can be done through Linked In. It is one of the best ways to socialize intelligently in order to know more people who may prove to be beneficial for you in near future.