In a LAN if i have ip phone sets , can they call them without need for Router or call Manager??

i design a network in a Head Quarter with which is a building with 13 floors and 30 Remote branches connected to the Head Quarter through 30 VPN connection also remote users will connect to the networj through the VPN concentrator which exist in the ...

what's the goal of USB ports in cisco devices?also from where i can know what's the order of cisco firewall between other firewalls?thanks alot

Hello,i have Main branch and 20 Branches, and i build a new network in the Main branch and other branches, so i want to build VOip solutions,,, so How can i start to build this sloution? also can i make integration between my PBX and the voip devices...

i have switch 6500 and 4500 can i make 4500 backup for 6500 as core switch?? Also if i have 2 switch Model 3750 and Dell Server can i take 2 copper cable from these 2 switches and make Ether Channel for these 2 cables from 2 switches???