gtpc1m30 | Transmission Control Protocol/Internet Protocol |
Transmission Control Protocol/Internet Protocol (TCP/IP) support provides a
set of C functions that applications can use to access the Internet for
transferring or receiving data called socket APIs.
Table 7 shows the types of sockets supported by TCP/IP and the
related protocol generally associated with each protocol.
Table 7. Socket Types and Associated Data
Socket type
| Protocol
| Description
|
SOCK_STREAM
| Transmission Control Protocol (TCP)
| The stream socket (SOCK_STREAM) interface defines a reliable
connection-oriented service. Data is sent without errors or duplication
and is received in the same order as it is sent.
|
SOCK_DGRAM
| User Datagram Protocol (UDP)
| The datagram socket (SOCK_DGRAM) interface defines a connectionless
service for datagrams, or messages. Datagrams are sent as independent
packets. The reliability is not guaranteed, data can be lost or
duplicated, and datagrams can arrive out of order. However, datagram
sockets have improved performance capability over stream sockets and are
easier to use.
|
SOCK_RAW
| IP, ICMP, RAW
| The raw socket (SOCK_RAW) interface allows direct access to lower-layer
protocols such as Internet Protocol (IP).
|
- Note:
-
The type of socket you use is determined by the data you are
transmitting:
- When you are transmitting data where the integrity of the data is high
priority, you must use stream sockets.
- When the data integrity is not high priority (for example, for terminal
inquiries), use datagram sockets because of their ease of use and higher
performance capability.
|
A socket address for the internet domain is made up of 4 distinct parts
defined by 16 bytes:
- The first 2 bytes contain the domain parameter, which indicates the
address space where communication is taking place.
- The next 2 bytes contain the port number, which the TCP/IP software used
to differentiate between different applications using the same protocol (TCP
or UDP).
- The next 4 bytes contain the internet address, which represents a unique
network interface.
- The remaining bytes in the 16-byte structure are not used.
The internet domain is the only address domain supported by TCP/IP
support.