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<concept id="GUID-F6460808-A806-5701-983E-CCD92EF3F688" xml:lang="en"><title>Networking

Services Quick Start</title><shortdesc>Networking Services provides a standard framework for accessing

network services and implementations of network protocols. The components

of the Networking Services are closely related to the framework provided by

the Communications Framework module. </shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<section><title>Getting started with Networking Services</title> <p>Networking

Services is used in the following circumstances: </p> <ul>

<li id="GUID-452B9F6E-82BF-5E2C-AF53-004208132D31"><p>If you are writing an

application or application level protocol that needs access to the Internet,

use the Internet Sockets interface and the Communications Framework Sockets

Server client. </p> </li>

<li id="GUID-943C19EF-20B3-5982-AF20-B90007DD2721"><p>If you are a licensee

and need to extend or modify the behaviour of the TCP/IP implementation, write

a plug-in using the IPHook interface. </p> </li>

<li id="GUID-69D9BDC0-BF27-526A-80E3-31DED2BCF956"><p>If you want to debug

existing application software and configure network settings. </p> </li>

</ul> </section>

<section><title>Architecture</title> <p>Networking Services enable mobile

devices to connect to the internet and network applications using protocols

such as TCP/IP and IPSec. The main areas of Networking Services are: </p> <ul>

<li id="GUID-506F919B-9E09-511B-823B-82210CAF5FD2"><p> <b>Link Layer Protocols</b>  </p> <p>The

Link Layer Protocols collection groups the networking protocols for the Data

Link Layer, including Ethernet and PPP. For more information, see <xref href="GUID-54757889-3FA3-5258-931F-27FF7DA447CB.dita">Link

Layer Protocols</xref>. </p> </li>

<li id="GUID-200F8660-6101-5C4D-9BB5-5C129A01E592"><p> <b>Network Security</b>  </p> <p>The

Network Security collection is the set of components that provide security

protocols for an IP connection. For more information, see <xref href="GUID-198A417F-EA4D-58A0-A928-A78FCE1BB772.dita">Network

Security</xref>. </p> </li>

<li id="GUID-F91DFA42-4A5F-5541-97CB-7B02FD0728DF"><p> <b>Network Test and

Utilities</b>  </p> <p>The Network Test and Utilities collection provides

components that are used to measure network performance. For more information,

see <xref href="GUID-55C8AEBD-7BB2-524C-9AED-5DFFD42AAD25.dita">Network Performance

Testing</xref>. </p> </li>

<li id="GUID-858A0576-6E7A-52CC-8895-83B247657941"><p> <b>Network Protocols</b>  </p> <p>The

Network Protocols collection is a set of plug-ins to the Sockets Server. The

plug-ins implement network protocols, such as TCP/IP, that can be accessed

through a sockets type interface. For more information, see <xref href="GUID-82438A0F-819C-5CDC-81DC-A8BFE3AA4A6A.dita">Network

Protocols</xref>. </p> </li>

<li id="GUID-E516FF95-8EC7-502E-914A-6987D8D04513"><p> <b>Network Control</b>  </p> <p>The

Network Control collection controls the resource availablity for applications

in mobile devices. It prioritises the applications on the device to ensure

performance consistancy and application access to the network. For more information,

see <xref href="GUID-B5E17404-4D2D-5EE3-B30B-DFDC5E0739FF.dita">Network Control</xref>. </p> </li>

<li id="GUID-98B26BD5-B245-533D-B3C5-AF56B7220F35"><p> <b>PPP Compression

Plugins</b>  </p> <p>This collection contains the Point-to-Point Protocol

(PPP) Compression Plugins used by the Point-to-Point Protocol component. For

more information, see <xref href="GUID-2EEA830C-1E2B-56D1-9104-F4A61FE0BA52.dita">PPP

Compression Plugins</xref>. </p> </li>

<li id="GUID-3B38421C-39C8-5832-AF53-4E513C542C58"><p> <b>TCP/IP Utilities</b>  </p> <p>The

TCP/IP Utilities collection provides libraries used by TCP/IPv4/v6 for the

DNS and DHCP protocols. For more information, see <xref href="GUID-7821C498-70A2-5D3C-989A-58CEBAE9162B.dita">TCP/IP

Utilities</xref>. </p> </li>

</ul> <p>The Symbian OS Networking Services structure can be compared to the

standard OSI Model for the layering of network protocols. The OSI Model defines

seven layers. Each layer defines a stage that data must go through to travel

from one device to another over a network. A layer corresponds to a group

of components that perform similar tasks in the Operating System. </p> <p>The

uppermost OSI Model layer is the Application Layer, which provides application

services to the end user software applications. The lowest OSI Model layer

is the Physical Layer, which deals with network connections and other physical

network attributes. </p> <p>The following section lists the OSI Model layers

and gives a brief description of each: </p> <ul>

<li id="GUID-0F603DB6-AF9B-5FD1-AAB9-329E7AC49353"><p> <b>Application Layer</b>  </p> <p>The

Application Layer interacts with the operating system or application when

the user wants to transfer files, read messages or perform other network related

activities. </p> </li>

<li id="GUID-48364975-5F2A-505D-BAE9-EC579578CA66"><p> <b>Presentation Layer</b>  </p> <p>The

Presentation Layer takes data from the Application Layer and converts it into

a format that the other layers can interpret. </p> </li>

<li id="GUID-B30EA44E-7C5F-52C1-B488-D95AC95E96FD"><p> <b>Session Layer</b>  </p> <p>The

Session Layer establishes, maintains, and ends communication with the receiving

device. </p> </li>

<li id="GUID-EC7EF5C1-AACA-5872-AF70-D3008ABAC525"><p> <b>Transport Layer</b>  </p> <p>The

Transport Layer takes the incoming data from applications and combines it

into a single stream. This stream is then passed on to the Network Layer. </p> </li>

<li id="GUID-99931DB9-25C1-558E-90B7-3BC3E8A62373"><p> <b>Network Layer</b>  </p> <p>The

Network Layer determines the way the data is sent to the recipient device.

Logical protocols, routing, and addressing are all dealt with in this layer. </p> </li>

<li id="GUID-88D80283-7D8A-5FA9-B6E3-18D6E9F47302"><p> <b>Data Layer</b>  </p> <p>The

Data Layer assigns physical protocol to the data. </p> </li>

<li id="GUID-4853FB9D-489A-5DDE-8281-26DC8365F580"><p> <b>Physical Layer</b>  </p> <p>The

Physical Layer defines the physical characteristics such as connections, voltage

levels and timing. </p> </li>

</ul> </section>

<section><title>Technologies</title> <p>The following table maps the various

communications technologies implemented in Symbian OS to the layers defined

by the OSI Model. Networking Services implements technologies that mostly

map to the Transport and Network Layers. Other Symbian OS modules implement

higher level application layer protocols and device drivers that implement

the bottom layers of the stack. </p> <table id="GUID-437DB8ED-936A-5DA0-A1B0-463A0DF0A80D">

<tgroup cols="1"><colspec colname="col0"/>

<tbody>

<row valign="middle">

<entry align="center">Application Layer</entry>

</row>

<row valign="top">

<entry align="center"><xref href="GUID-69B46D92-8D07-5B42-B603-3F725977AA4A.dita">DHCP</xref>     

¦      <xref href="GUID-F532D96F-7CB0-5CC7-9382-0CF44F7C0234.dita">DNS</xref>      ¦

      FTP      ¦     <xref href="GUID-B4A54501-4AA4-5ACB-96D7-4427C7752639.dita">HTTP</xref>     

¦     <xref href="GUID-993629CB-17B4-5E87-8DE1-06A4AC473FDD.dita">RTCP</xref>     

¦      <xref href="GUID-093516F2-9076-5A96-9BEF-F5A77F75239C.dita">SIP</xref>      

¦     TELNET</entry>

</row>

<row valign="top">

<entry align="center">Presentation Layer</entry>

</row>

<row valign="top">

<entry align="center"><xref href="GUID-3D20F136-4526-502D-A708-1F26550FC61A.dita">TLS/SSL</xref></entry>

</row>

<row valign="top">

<entry align="center">Session Layer</entry>

</row>

<row valign="top">

<entry align="center"><xref href="GUID-993629CB-17B4-5E87-8DE1-06A4AC473FDD.dita">RTP</xref></entry>

</row>

<row valign="top">

<entry align="center"> Transport Layer</entry>

</row>

<row valign="top">

<entry align="center"><xref href="GUID-A9640739-462C-5D95-8DCC-D273CD8439AE.dita">TCP</xref>        

¦       <xref href="GUID-A9640739-462C-5D95-8DCC-D273CD8439AE.dita">UDP</xref> </entry>

</row>

<row valign="top">

<entry align="center"> Network Layer</entry>

</row>

<row valign="top">

<entry><xref href="GUID-A9640739-462C-5D95-8DCC-D273CD8439AE.dita">IP (IPv4/IPv6)</xref>    

¦       <xref href="GUID-7BACF7C1-0762-53E6-A507-1395016811D6.dita">IPsec</xref></entry>

</row>

<row valign="top">

<entry align="center"> Data Link Layer </entry>

</row>

<row valign="top">

<entry align="center"><xref href="GUID-9330621E-1400-5F52-BACB-48DB814E2922.dita">Ethernet</xref>     

¦      <xref href="GUID-8F565241-149E-5AF7-972E-A06B6DDC1B9F.dita">GPRS</xref> </entry>

</row>

<row valign="top">

<entry align="center"> Physical Layer </entry>

</row>

<row>

<entry align="center"><xref href="GUID-36AF783B-A56A-5C16-A055-9075ED4396C5.dita">RS232</xref>    

¦    Ethernet Physical Layer     ¦

     <xref href="GUID-9B83CDD4-FC94-51A0-AC67-CD04BCAFEF08.dita">Serial

Communications</xref>       ¦               <xref href="GUID-DE2E64A5-417A-538C-904B-6D498BB55273.dita">USB</xref>  </entry>

</row>

</tbody>

</tgroup>

</table> </section>

</conbody></concept>