Internet Protocol (IP) for IPv4
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4/8/2010
IP is the mailroom of the TCP/IP stack, where packet sorting and delivery take place. At this layer, each incoming or outgoing packet is referred to as a datagram. Each IP datagram bears the source IP address of the sender and the destination IP address of the intended recipient. Unlike the MAC addresses, the IP addresses in a datagram remain the same throughout a packet's journey across an inter-network. IP layer functions are described below.
IP is central to the TCP/IP stack — all other TCP/IP protocols use IP — and all data passes through it. IP is a connectionless protocol and has some limitations. If IP attempts packet delivery and in the process a packet is lost, delivered out of sequence, duplicated, or delayed, neither sender nor receiver is informed. Packet acknowledgement is handled by a higher-layer transport protocol, such as TCP.
IP is responsible for addressing and routing packets between hosts, and for fragmentation. Fragmentation is the process of breaking a datagram into smaller pieces for inter-network routing. IP fragments packets prior to sending them and reassembles them upon receipt.
Note
Winsock applications can send packets, but cannot affect packet routing or fragmentation.
Windows CE .NET 4.1 and later provides a dual protocol stack to support 32-bit IPv4 addresses and 128-bit IPv6 addresses. For information about the stack architecture, see Dual Stack Architecture.
The following table shows links to more information about IPv4.
| Area | IPv4 topics |
|---|---|
Addressing, name registration and name resolution |
|
Routing |
|
Subnet multicasting |
See Also
Concepts
Core Protocol Stack for IPv4
IPv6 and IPv4 Coexistence
Internet Protocol (IP) for IPv6