1 votes 1 votes A small doubt we know that, in class A, the 31st bit is 0. i.e. First octet is - 0 _ _ _ _ _ _ _ then minimum value is 0 and 127. But we say that, Range of first octet is (1,127). I am confused here, please help me to understand this Computer Networks computer-networks network-addressing ip-addressing + – AnilGoudar asked Jul 14, 2017 AnilGoudar 573 views answer comment Share Follow See all 2 Comments See all 2 2 Comments reply joshi_nitish commented Jul 14, 2017 reply Follow Share because 0.0.0.0 is used for default routes in routers.. 0 votes 0 votes Deepak Kumar 12 commented Jul 15, 2017 reply Follow Share According to Wikipedia Range: 0-127(Class-A) If the first bit of the first octet of an IP address is a binary 0, the address is a Class A address. With that first bit being a 0, the lowest number that can be represented is 00000000, decimal 0. The highest number that can be represented is 01111111, decimal 127. Any address that starts with a value between 0 and 127 in the first octet is a Class A address. These two numbers, 0 and 127, are reserved and cannot be used as a network address. 0.0.0.0 Me”: (Alternately, “this host”, or “the current/default host”). Used by a device to refer to itself when it doesn't know its own IP address. The most common use is when a device attempts to determine its address using a host-configuration protocol like DHCP. May also be used to indicate that any address of a multihomed host may be used. 127.x.y.z loop back addresses(except 127.0.0.0 and 127.255.255.255). 1 votes 1 votes Please log in or register to add a comment.
0 votes 0 votes https://www.tutorialspoint.com/ipv4/ipv4_address_classes.htm Refer this. it will clear all your doubts. Gaurav Joshi answered Jul 15, 2017 Gaurav Joshi comment Share Follow See all 0 reply Please log in or register to add a comment.