iOS Networking
CS328
Big Picture
Core Foundation Networking
• CF Networking APIs are abstractions on top of the
BSD sockets to make it easier to program network
protocols.
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working with BSD sockets
Creating and using SSL and TLS
Resolving DNS host requests
Working with HTTP
Working with FTP
Publishing , resolving and browsing Bonjour services
CF Network Concepts
• Low level, high performance framework to
give detailed control over the protocol stack
• An extension of BSD sockets
CFSocket and CFStream
• CFSocket and CFStream are fundamental to
CFNetwork
• First we’ll look at both before looking at
CFNetwork
CFSocket
• Most basic level of network communication
• Uses BSD Socket but the abstraction allows
the CFSocket to be integrated with a program
run-loop.
• Can also be used for UDP sockets.
CFSocket
• CFSocketCreate – makes a CFSocket from
scratch
• CFSocketCreateWithNative – Create a
CFSocket out of a BSD socket
• CFSocketCreateRunLoopSource – Create a
CFSocket to use in a program run loop.
• CFSocket Reference
CFStream
• Provides the abstraction to read and write
information from one socket on the local
machine and another on a remote machine
(could also be on the local machine).
• Streams can be attached to memory, files or
sockets/network
• CFReadStream
• CFWriteStream
The Framework
Using
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Use in the same way as a UNIX stream
Create the stream (instantiate it)
Open it
Read or write it.
Close/Dispose of
CFStream Reference
Other CFNetwork APIs
• CFFTP – create read/write streams for
uploading and downloading files from FTP
servers. This implements the FTP protocol
• CFHTTP - create read/write streams for
sending HTTP Requests and receiving HTTP
Response packets. This implements the HTTP
protocol
• CFHTTPAuthentication – provides for
interfacing with an HTTP server set up for
challenge/response authentication.
• CFHost – Lets you query host information
from DNS.
• CFNetServices – Interface to Bonjour.
Bonjour
• Bonjour is Apple Inc.'s trade name for its
implementation of Zeroconf, a group of
technologies that includes service discovery,
address assignment, and name resolution.
Bonjour locates devices such as printers, other
computers, and the services that those
devices offer on a local network using
multicast Domain Name System (mDNS)
service records.
Zeroconf
• Zero configuration networking (zeroconf), is a
set of techniques that automatically creates a
usable Internet Protocol (IP) network without
manual operator intervention or special
configuration servers.