Not sure of online certification.... But yes u can have online training for GIAC certified courses....

Now these courses are extensive and cover all concepts that u would need to know when u involve in inf. security profession....

All said.... Agree with HTRegz that breaking a system is a much simpler job.. But what makes the profession unique is the challenge to prevent ur inf. assets from getting hacked from so many threats that it is exposed....

Remember a famous quote on Information Secuirty.. " YOU ARE AS SECURED AS YOUR WEAKEST LINK" ... Simple example would be that you may have the best lock avaiable attached to your door... But if the walls are weak or if windows are not properly secured and intruder can still get an access to your territory.....

Hence : Cetifications help.. but you should equip yourself with extensive knowledge on inf. security.... have to dirty ur hands by actually working with tools..... and yes a decent knowledge of network is a must.....

BTW... being a oracle expert.. as mentioned by someone u can also take up database security as ur line of interest....