Thread: Telnet, ftp, icmp Layer

At which layer dose telnet, ftp, icmp works ?

application layer .

hi guys how r u

class a 1 to 126
class b 128to 191

class c 192 to 223

Hello, protocols, in a nutshell, application layer protocols like http, smtp, ftp presentation layer protocols like jpeg, mpeg session layer protocols like nfs, sql, rpc transport layer protocols like tcp, and udp network layer protocols like ip and icmp data link layer protocols like hdlc and ppp physical layer no protocols at this layer (wire / wireless)