Unable to access another computer by computer name

Unable to access another computer by computer name

I am having a Laptop with vista premium. I have setup wireless connection. I am having BSNL ADSL Modem for broadband and also i am using it as a wireless router from router i had connected one port to my linksys router which was connected to another computer in my network. I had also one wired connection which direcly connect to linksys router.