In the WAN topology, a network is divided usually by the firewall into the 'outside' or public IP addresses and the 'inside' or private IP addresses.  The is done because public IP addresses (provide...

the address which can't be routed through public (internet) are private ip addresses
and it is scheam of saving public address
ex:in class A range is10.0.0.0 to 10.255.255.255
        

collectioon of related files stored in a perticuler location is called file syetem.there three types of file system i disk based filesystem and 2 is network based file system and the other one is virt...

FAT16-File Allocation Table 16-bit Supports upto DOS6.22 Windows 3.1/3.11/95/98
FAT32-File Allocation Table 32-bit Supports Windows 95/98/Windows 2000/xp/2003
HPFS-High Performance Fils System Supports NT/2000/xp/2003
NTFS-New Technoloy File System Supports NT/2000/xp/2003

telnet- 23
ftp-21/20
snmp- 161/162

Telnet = 23
SNMP = 161
FTP= 20 for connection establishment and 21 for Data Transfer.