The TTL field contains a counter value set by the source host. Each gateway that processes this datagram, decreases the TTL value by one. When the TTL value reaches zero, the datagram is discarded.
All the datagram headers in the TCP/IP protocol suite are transmitted in the "big endian" byte order. i.e. The most significant byte is transmitted first. This is also called as "network byte order".
The size of the IP header is not fixed. Depending on the IP options present, the size of the IP header will vary. A separate field for the IP header length is added, so that the destination system can separate the IP datagram header from the payload.
If a datagram cannot be delivered to the destination host due to some reason, it is considered an undeliverable datagram.
The typical value for a TTL field is 32 or 64.
RFC 1349 discusses the Type Of Service (TOS) field.
The TTL field is used to limit the lifetime of a IP datagram and to prevent indefinite looping of IP datagrams.
Time To Live is used to limit the period of time of transmission of network technology that ba unit of data can experience before it should be discarded. .
Yes. The IP datagram identifier field is different for each IP datagram transmitted. The fragments of an IP datagram will have the same identifier value.